CN113352538B

CN113352538B - Method for preparing shell assembly with ceramic appearance, shell assembly and electronic device

Info

Publication number: CN113352538B
Application number: CN202110594743.6A
Authority: CN
Inventors: 胡梦; 陈奕君; 李聪
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2021-05-28
Filing date: 2021-05-28
Publication date: 2022-11-15
Anticipated expiration: 2041-05-28
Also published as: CN113352538A

Abstract

The present invention relates to a method of preparing a housing assembly having a ceramic appearance, the method comprising: mixing inorganic filler, organic resin and an auxiliary agent to form a mixed material; banburying and granulating the mixed material to form granules; performing injection molding on the granules to form a blank body; carrying out warm isostatic pressing treatment on the blank; carrying out heat treatment on the blank subjected to the warm isostatic pressing treatment to obtain a shell assembly; wherein the inorganic filler comprises a first filler, a second filler, a third filler, and a peroxide; the first filler and the second filler are respectively selected from a rod-shaped filler and a flake-shaped filler. From this, rodlike filler and slice filler pass through peroxide for filler overlap joint takes place chemical reaction and forms the strong chain, forms complete continuous network skeleton, and the heat can carry out quick conduction through continuous network skeleton, and housing assembly has higher coefficient of heat conductivity, and is close with ceramic coefficient of heat conductivity.

Description

Method for preparing housing component with ceramic appearance, housing component and electronic device

Technical Field

The invention belongs to the technical field of shells, and particularly relates to a method for preparing a shell assembly with a ceramic appearance, the shell assembly and electronic equipment.

Background

With the continuous development of 3C electronic products, the product forms are increasingly rich, and the requirements of users on the appearance and the texture of the products are higher and higher. Common plastic materials cannot meet the user experience requirements due to low product hardness, poor scratch resistance and poor texture. Ceramic materials with high gloss, high hardness, and high quality are increasingly popular with users. However, the ceramic material has high density, is difficult to form in a complex structure, and is difficult to meet the requirements of consumers on light weight and rich/diversified forms of products. In addition, the ceramic product has high hardness, difficult processing, long processing time, high cost and low yield, so that mass production and low cost of the ceramic product are limited, and the popular requirements of the ceramic product are difficult to meet.

At present, in order to solve the problems of low hardness and low glossiness of plastic ceramic-like parts, difficult ceramic forming, high processing difficulty and high price, a small number of researchers prepare ceramic-like composite materials which have the characteristic of easy plastic forming and have higher glossiness and hardness than plastics by compounding resin and ceramic powder. However, the thermal conductivity of the composite material is greatly different from that of ceramics, and the composite material is difficult to feel cool like ceramics.

Disclosure of Invention

To improve the above technical problem, the present invention provides a method of preparing a case assembly having a ceramic appearance, the method comprising: mixing inorganic filler, organic resin and an auxiliary agent to form a mixed material; carrying out banburying granulation on the mixed material to form granules; performing injection molding on the granules to form a blank body; carrying out warm isostatic pressing treatment on the blank; carrying out heat treatment on the blank subjected to the warm isostatic pressing treatment to obtain a shell assembly; wherein the inorganic filler comprises a first filler, a second filler, a third filler, and a peroxide; the first filler and the second filler are respectively selected from a rod-shaped filler and a flake-shaped filler. Therefore, according to the method, the rod-shaped filler and the sheet-shaped filler are subjected to chemical reaction through peroxide, so that strong links are formed at the lap joints of the fillers, a continuous and complete network framework is formed, heat can be quickly conducted through the continuous network framework, the shell assembly has a high heat conductivity coefficient, the heat conductivity coefficient of the shell assembly is equivalent to that of ceramic, and the shell assembly has a cool feeling of ceramic.

The invention also provides a housing component having a ceramic appearance, the housing component being prepared by the method described hereinbefore. Thus, the housing assembly has all the features and advantages of the method described above, which are not described in detail herein.

The invention also provides a housing assembly having a ceramic appearance, comprising an organic filler and an inorganic filler, the inorganic filler comprising a first filler, a second filler, a third filler and a peroxide; the first filler and the second filler are respectively selected from a rod-shaped filler and a platy filler. Therefore, the rod-shaped filler and the sheet-shaped filler can form strong links through peroxide to form a compact continuous network framework, heat can be quickly conducted through the network framework, and the shell component has a high heat conductivity coefficient and is equivalent to that of ceramic.

The present invention also provides an electronic device, including: the display screen assembly, the main board and the shell assembly; the housing assembly is the housing assembly having a ceramic appearance described above; the display screen assembly is connected with the shell assembly, and an installation space is defined between the display screen assembly and the shell assembly; the mainboard is established in the installation space and with display screen subassembly electricity is connected. Thus, the electronic device has all the features and advantages of the housing assembly with ceramic appearance described above, and will not be described herein again.

Drawings

FIG. 1 is a flow chart of a method of making a housing assembly having a ceramic appearance in accordance with one embodiment of the present invention;

FIG. 2 is a flow chart of a method of making a housing assembly having a ceramic appearance in accordance with another embodiment of the present invention;

FIG. 3 is a flow chart of a method of making a housing assembly having a ceramic appearance in accordance with another embodiment of the present invention;

FIG. 4 is a flow chart of a method of making a housing assembly having a ceramic appearance in accordance with yet another embodiment of the present invention;

fig. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Description of the reference numerals:

100-housing assembly, 200-display screen assembly.

Detailed Description

Embodiments of the present application are described in detail below. The following description of the embodiments is merely exemplary in nature and is in no way intended to limit the present disclosure. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents used are conventional products which are not indicated by manufacturers and can be obtained by market purchase.

The prior composite material of resin and ceramics has larger difference of heat conductivity coefficient with ceramics, does not have cool feeling like ceramics, and has poorer texture of ceramics.

To improve the above technical problem, the present invention provides a method of preparing a case assembly having a ceramic appearance, which comprises, with reference to fig. 1:

s100, mixing inorganic filler, organic resin and auxiliary agent to form mixed material

In this step, the inorganic filler, the organic resin and the auxiliary agent are mixed to form a mixed material. Wherein the inorganic filler comprises a first filler, a second filler, a third filler and peroxide, and the first filler and the second filler are respectively selected from a rod-shaped filler and a sheet-shaped filler. Therefore, in the subsequent reaction process, the first filler and the second filler can be tightly overlapped together through peroxide to form a compact continuous framework structure, the compact continuous framework structure can quickly conduct heat, and the shell assembly has high heat conductivity coefficient.

In one embodiment of the present invention, the rod-shaped filler may be formed of a high thermal conductive material, and the plate-shaped filler may be formed of a high refractive material. Thereby, the thermal conductivity and the glossiness of the case assembly may be further improved. Specifically, the flaky fillers tend to be arranged in a horizontal direction through adjustment of subsequent operations, and the rod-shaped fillers form chain connection in a system to form a network structure. Therefore, the high-heat-conduction material is selected to form the rod-shaped filler, so that the heat conductivity of the network structure can be better improved, and the sheet-shaped material formed by the high-refraction material can provide better brightness and glossiness, so that the ceramic appearance effect of the finally formed shell assembly is improved.

In the present invention, the thermal conductivity of the above-mentioned high thermal conductive material and the refractive index of the high refractive material are not particularly limited as long as they are higher than those of general inorganic fillers and have the effect of improving the glossiness and the thermal conductivity. The selection can be made by one skilled in the art based on the specific ceramic-like requirements of the housing assembly.

The morphology of the third filler is not particularly limited, and specifically may be at least one of a spindle type and a spheroidal type. The inventor finds that the first filler and the second filler have poor dispersibility in the mixed material, and if the inorganic filler does not include the third filler, the solid content of the inorganic filler in the prepared mixed material is low, and the prepared shell assembly cannot well disperse heat, that is, the prepared shell assembly has poor thermal conductivity, the prepared shell assembly has a large difference in thermal conductivity with ceramic, and the prepared shell assembly has poor glossiness. Through adding the third filler in the inorganic filler, can promote the solid content of inorganic filler in the compounding, promote the content of first filler and second filler in the compounding promptly, the quick conduction of heat can be had with the casing subassembly of preparation, and the coefficient of heat conductivity of the casing subassembly of preparation is great. In one embodiment of the invention, the particle size of the third filler is 200nm-5 μm, and at this particle size, the solid content of the inorganic filler in the mixed material can be further increased, and the thermal conductivity coefficient of the shell component can be further increased, so that the shell component has better ceramic texture.

Further, the third filler of a desired particle size may be prepared by a sanding process. Specifically, the sanding cycle number is 10-100 times, the sanding solvent can be ultrapure water or a mixed solvent of alcohol and water, the sanding rotating speed is 300-1500r/min, the grain size of the sanding zirconium beads can be 0.5-10 mm (single grain size zirconium beads or mixed grain size zirconium beads), and the mass of the zirconium beads is 20-30kg. Further, in the sanding step, a dispersant and a surface modifier may also be added. The dispersant can be at least one of sodium benzoate, polyester and sodium hexametaphosphate, and the dosage of the dispersant can be 0.3-2% of the mass of the third filler. The surface modifier can be at least one of titanate, aluminate and silane coupling agent, and the dosage of the surface modifier is 0.5-3% of the mass of the inorganic powder. The third filler with the particle size of 200nm-5 mu m can be prepared by coordinating and controlling the parameters of the sand grinding process.

Further, the first filler comprises Si and Al ₂ O ₃ 、AlN、ZrO ₂ 、Si ₃ N ₄ SiC, the second filler comprises Si and TiO ₂ 、ZrO ₂ At least one of (1), the third filler including Al ₂ O ₃ 、ZrO ₂ And SiC. The inorganic filler formed by the materials has better performance and meets the requirements of the first filler and the second fillerThe material has the requirements for high heat conduction or high light conduction, the third filler has appropriate material hardness and is easy to obtain, and the morphology or particle size meeting the requirements of the third filler can be formed for improving the dispersibility of the first filler and the second filler in the mixed material.

In one embodiment of the present invention, a method of forming an inorganic filler comprises: and mixing peroxide with the first filler and the second filler, and then mixing a third filler with the first filler, the second filler and the peroxide to obtain the inorganic filler.

Further, after the peroxide is mixed with the first filler and the second filler, a drying step may be performed, the drying temperature is lower than the decomposition temperature of the peroxide selected, the present invention is not limited to the drying degree, and the skilled person may select the drying temperature according to the use requirement.

Further, when the peroxide is mixed with the first filler and the second filler, the ratio of the peroxide to the sum of the masses of the first filler and the second filler is (1-3): 100. according to the invention, the peroxide is mixed with the first filler and the second filler, so that the peroxide can be adsorbed to the surfaces of the first filler and the second filler, and the peroxide is small molecules, and is not easy to fall off in the step of preparing the mixed material due to the size effect. In the subsequent reaction step, the peroxide can generate strong interaction at the connecting point of the first filler and the second filler to form a compact continuous framework structure, so that the heat conductivity coefficient of the shell assembly is further improved.

If the mode of mixing peroxide with the first filler and the second filler is not adopted, and the peroxide is added into materials comprising the first filler, the second filler, the third filler, organic resin and the like during the preparation of the mixed material, compared with the mode of mixing the peroxide with the first filler and the second filler, the mode of adding the peroxide during the preparation of the mixed material needs to add more peroxide, namely the using amount of the peroxide needs to be increased, and the peroxide can be distributed in the whole system, so that in the subsequent reaction step, strong interaction cannot be generated at the connecting point of the rod-shaped filler and the sheet-shaped filler, the efficiency of heat conduction is reduced, more peroxide can generate side reaction, more peroxide can enable a molecular chain to generate strong crosslinking reaction, and further the finally prepared shell component has the defect of poor toughness and has the adverse effect of low heat conduction coefficient. The invention adopts the mode of mixing the peroxide with the first filler and the second filler, can avoid the defects and adverse effects and can ensure that the finally formed shell assembly has higher heat conductivity coefficient. The peroxide comprises at least one of ammonium persulfate, potassium persulfate, hydrogen peroxide and benzoyl peroxide.

Further, based on the total mass of the mixed materials, the content of the inorganic filler is 50-90 parts by weight, the content of the third filler is 50-85 parts by weight, the sum of the contents of the first filler, the second filler and the peroxide is 5-30 parts by weight, the content of the organic resin is 5-45 parts by weight, and the content of the auxiliary agent is 0.1-1 part by weight. The auxiliary agent includes, but is not limited to, a cosolvent and a leveling agent, and the specific components of the cosolvent and the leveling agent are not limited in the present invention, and can be selected by the skilled person according to the use requirement. When the compounding adopts above-mentioned constitution, can further promote the coefficient of heat conductivity of casing subassembly.

Illustratively, the organic resin includes at least one of pyridinium propane sulfonate (3- (1-pyridine) -1-propane sulfonate, PPS), polycarbonate (PC), polyamide (PA), and polymethyl methacrylate (PMMA).

The mixing mode of the inorganic filler, the organic resin and the auxiliary agent is not limited in the invention. Illustratively, in the step of forming the compounded material, the inorganic filler, the organic resin and the auxiliary agent may be ball-milled and blended. For example, the inorganic filler, the organic resin and the auxiliary agent are proportionally added into a roller filled with zirconium beads for ball milling and blending, the ball milling time is 0.5 to 8 hours, and the ball milling rotating speed is 200 to 1000r/min.

S200, banburying and granulating the mixed material to form granules

In this step, the mixed material is subjected to banburying granulation to form pellets. Further, the temperature of banburying is 150-350 ℃, the banburying time is 0.5-6h, the banburying rotation speed is 5-100r/min, and the banburying pressure is less than 0.01MPa, or banburying granulation is carried out under the protection of inert gas, including but not limited to nitrogen and argon, in the step, banburying is carried out under the condition of inert gas or smaller pressure, thereby avoiding the side reaction of oxygen and particles. And extruding and granulating after banburying.

S300, carrying out injection molding on the granules to form a blank

In this step, the pellets are injection molded to form a green body. During injection molding, the temperature of an injection nozzle is 200-350 ℃, the injection pressure is 80-120Mpa, the injection speed is 50-95%, the mold temperature is 100-260 ℃, the pressure maintaining pressure is 30-100Mpa, and the pressure maintaining time is 5-50s. The inventor finds that the high injection speed, the injection pressure, the large holding pressure and the time in the range are favorable for the horizontal orientation arrangement of the platy fillers on the surface layer, and the rod-shaped fillers are linked into a complete network in the system. The flaky fillers arranged in the horizontal orientation can further improve the glossiness of the finally prepared shell assembly, and the formed complete network is favorable for quickly conducting heat, so that the finally prepared shell assembly has higher heat conductivity coefficient.

S400, carrying out warm isostatic pressing treatment on the blank

In this step, the green body is subjected to warm isostatic pressing. Further, the blank is subjected to vacuum sealing and warm isostatic pressing. The temperature of the warm isostatic pressing treatment is higher than the glass transition temperature of the organic resin, and can be, for example, 80-300 ℃ and the working pressure is 50-500MPa. Further, the time of warm isostatic pressing treatment is 15-30 minutes. Under the condition that the temperature is higher than the glass transition temperature of the organic resin, the high-pressure treatment can help to eliminate air holes and defects in the green body, simultaneously enhance the compactness of the green body, compress/eliminate gaps among the fillers, enable the flaky fillers and the rodlike fillers to be mutually overlapped to form a continuous and complete network framework, and improve the system strength and the heat conduction and heat soaking characteristics.

S500, carrying out heat treatment on the blank subjected to the warm isostatic pressing treatment to obtain a shell assembly

In this step, the blank after the warm isostatic pressing treatment is subjected to a heat treatment to obtain a housing component. The heat treatment temperature is 100-350 deg.C, such as 100 deg.C, 120 deg.C, 150 deg.C, 180 deg.C, 200 deg.C, 230 deg.C, 250 deg.C, 280 deg.C, 300 deg.C, 310 deg.C, 320 deg.C, 330 deg.C, 340 deg.C, 350 deg.C, and the heat treatment time is 6-36 hours, such as 6 hours, 10 hours, 15 hours, 20 hours, 24 hours, 25 hours, 30 hours, 35 hours, 36 hours. The peroxide on the surfaces of the rod-shaped filler and the flaky filler can be excited through long-time high-temperature treatment, so that the lap joint of the filler is subjected to chemical reaction to form a strong link, and the skeleton strength of the filler and the comprehensive heat conductivity coefficient of the shell assembly are further improved. Meanwhile, for the non-filler lap joint, the peroxide on the surface of the filler can promote the organic resin to generate chain scission/chain extension and be chemically grafted to the surface of the filler, so that the compatibility and the connecting force of the filler and the organic resin are greatly improved, and the toughness of the composite material is further improved. The comprehensive heat conductivity coefficient of the shell assembly after heat treatment reaches 1.8-8W/(m.K) and is far higher than that of plastic, the shell assembly prepared by the method has the heat conductivity coefficient equivalent to that of ceramic, has cool feeling like ceramic in touch sense, and overcomes the defect of poor heat conductivity coefficient of the existing resin ceramic composite material.

In order to further improve the appearance effect of the resin ceramic composite material, in one embodiment of the present invention, after the heat treatment, referring to fig. 2, the method further includes:

s600, polishing the shell assembly.

In this step, the housing assembly is subjected to a polishing process. Specifically, the polishing process may include rough polishing, middle polishing, and finish polishing. And removing the surface layer by rough polishing, wherein the removal amount of the rough polishing can be 50-500 mu m, repairing the defects of the rough polishing by middle polishing, and finally performing fine polishing. So that the surface of the shell component achieves the effect of a ceramic mirror surface and luster. Wherein the surface roughness of the material after the fine polishing is equivalent to the surface roughness of the mirror surface ceramic after the polishing. Meanwhile, the high-thermal-conductivity rod-shaped filler and the high-refraction sheet-shaped filler are orderly arranged on the surface, so that the glossiness of the polished surface at 20 degrees, 60 degrees and 80 degrees is equivalent to the glossiness of the polished surface of the ceramic at different angles.

The inventor also finds that the surface energy, the friction coefficient and the hydrophilicity and hydrophobicity of the existing resin ceramic composite material are greatly different from those of the ceramic, so that the existing resin ceramic composite material is difficult to have the visual and tactile effects of the ceramic.

In order to further enhance the appearance effect of the resin ceramic composite material, in an embodiment of the present invention, after the polishing process, referring to fig. 3, the method further includes:

s700, performing surface treatment on the shell assembly

In this step, the case assembly is subjected to surface treatment. Specifically, the surface treatment includes any one of the following manners: carrying out plasma treatment on the shell assembly, and then carrying out microetching treatment; alternatively, the housing assembly is coated.

The plasma treatment includes: the surface of the housing assembly is treated with plasma. The power of the plasma is 150-500W, and under the power, the long chains of the organic resin on the surface layer of the shell component can be subjected to crosslinking/crystallization rearrangement after chain breaking, so that the rigidity of the organic resin is improved, the energy loss of the organic resin under stress is reduced, and the aim of reducing the friction coefficient is fulfilled. The plasma treatment is carried out under the inert gas protection or vacuum condition, so that a series of problems that the organic resin on the surface of the shell assembly is increased in polarity, the molecular arrangement is changed, the compactness is reduced, the glossiness is reduced and the like caused by hydroxyl generated by the reaction of activated/broken polymer chain breaks in the plasma treatment and water vapor or oxygen can be avoided. Further, the inert gas may be nitrogen or argon. It should be noted that, since it is difficult to achieve an absolute vacuum, when the pressure in the system is less than 100mt, that is, the pressure in the system is less than 133Pa, it is considered as a vacuum condition. The plasma treatment time is 5-60s. The plasma treatment can reduce the coefficient of friction of the housing assembly. Compared with the shell assembly before treatment, the 20 DEG, 60 DEG and 80 DEG glossiness of the surface of the shell assembly after plasma treatment is respectively equivalent to that before treatment, and the friction coefficient is reduced.

The microetching treatment comprises the following steps: and soaking the shell assembly into a weak acid solution to perform reaction. Specifically, the weak acid comprises at least one of citric acid and acetic acid, the mass concentration of the weak acid solution is 0.1-1%, the reaction temperature of the micro-etching treatment is 5-10 ℃, and the reaction time of the micro-etching treatment is 5-30s. The microetching increases the density of hydrophilic hydroxyl groups on the surface of the shell component exposed to air after polishing, and improves the hydrophilic property and surface energy of the surface of the shell component. The surface roughness of the shell component after the microetching is equivalent to that before the treatment, and the surface water drop angle is reduced. The micro-etching of the invention can reduce the water drop angle of the surface of the shell component, and avoid surface pits formed by over-etching, and has the advantage of not influencing the surface roughness and the optical characteristics.

The coating comprises the following steps: a layer of ceramic material is deposited on a surface of the housing assembly. The thickness of the ceramic material layer is not particularly limited and may be, for example, 10 to 30nm. The shell component can have the characteristics of ceramic materials through film coating, so that the surface energy, the surface hydrophilicity and hydrophobicity and the surface friction coefficient of the shell component are consistent with the correlation coefficient of ceramics, the thickness of the ceramic material layer is moderate, the optical and thermal characteristics of the body of the shell component are not influenced, and the surface of the shell component can be closer to the specific physical properties of the ceramic materials. The inventors have found that, in addition to the thermal conductivity of the material constituting the housing member having a large influence on the final touch feeling of the housing member (providing a tactile cooling feeling), the touch feeling of the surface of the housing member can be made closer to the ceramic material by adjusting the surface energy, the surface hydrophilicity and hydrophobicity, and the surface friction coefficient of the housing member.

Further, the deposition method is an atomic layer deposition method, the ceramic material is at least one of alumina and zirconia, the deposition precursor comprises at least one of trimethylaluminum and trimethylzirconium, the deposition reaction pressure is 0.1-10mbar, the deposition reaction temperature is 50-500 ℃, and the deposition reaction rate is 5-20nm/h.

According to an embodiment of the present invention, after the heat treatment, referring to fig. 4, the method may further include:

and S800, introducing organic olefin containing double bonds to the surface of the shell assembly to form a permeable layer.

Further, a method of forming the transparent layer includes ultraviolet irradiation or plasma excitation, which can promote the polymerization of the above organic olefin. Exemplary, organic olefins containing double bonds include, but are not limited to, at least one of styrene, acrylic acid. Therefore, the surface hardness and the modulus of the shell assembly can be further improved under the condition of not influencing other surface characteristics, a transparent surface visual effect is given to the shell assembly, and the ceramic texture of the shell assembly is more excellent.

Further, the step of preparing the permeation layer may be performed after the surface treatment is performed. Alternatively, the operation of forming the through layer may be performed after the polishing process, instead of the surface treatment.

The specific structure of the housing assembly is not particularly limited, and may be, for example, a 2D, 2.5D or 3D housing, and the included angle between the side wall and the bottom surface of the housing assembly is also not particularly limited. As mentioned above, the housing assembly can be formed by injection molding, so that a housing assembly with a larger bending angle or a curved surface can be formed.

The invention also provides a housing assembly having a ceramic appearance. The shell component comprises organic filler and inorganic filler, wherein the inorganic filler comprises first filler, second filler, third filler and peroxide, and the first filler and the second filler are respectively selected from rod-shaped filler and sheet-shaped filler. Therefore, the first filler and the second filler can form strong links through peroxide to form a continuous and complete network framework, heat can be quickly conducted through the continuous network framework, the heat conductivity coefficient of the shell assembly can be improved, and the heat conductivity coefficient of the shell assembly is close to that of ceramic.

According to some embodiments of the present invention, the housing assembly with a ceramic appearance may have the same features and advantages as the housing assembly obtained by the method described above, and will not be described herein again.

The present invention also provides an electronic device, and referring to fig. 5, the electronic device includes: the display screen assembly comprises a display screen assembly 200, a mainboard and a shell assembly 100, wherein the shell assembly 100 is the shell assembly with the ceramic appearance, the display screen assembly 200 is connected with the shell assembly 100, an installation space is defined between the display screen assembly 200 and the shell assembly 100, and the mainboard is arranged in the installation space and is electrically connected with the display screen assembly 200.

The specific type of electronic device is not particularly limited by the present application and, for example, the electronic device may be a cell phone, a smart watch, a palmtop computer, a notebook computer, a laptop computer, a desktop computer, a portable gaming device, a video recorder, a camera, a pager, or a printer, among others. In particular, the electronic device may be a mobile or smart phone (e.g., an iPhone (TM) based, android (TM) based phone), a Portable gaming device (e.g., a Nintendo DS (TM), a PlayStation Portable (TM), a Game Advance (TM), an iPhone (TM)), a PDA, a Portable Internet device, a music player and data storage device, other handheld devices and headsets such as watches, earphones, pendant, headphones, etc., and other wearable devices (e.g., a Head Mounted Device (HMD) such as electronic glasses, electronic clothing, electronic bracelets, electronic necklaces, electronic tattoos, or smartwatches). Thus, the electronic device has all the features and advantages of the housing assembly described above, and will not be described herein.

The examples described below in this application, unless otherwise indicated, all reagents used are either commercially available or can be prepared by the methods described in this application.

Example 1

(1) A third filler of the desired particle size is prepared by sanding. The third filler is Al ₂ O ₃ . The sanding cycle is 10-100 times, the sanding solvent is a mixed solvent of ultrapure water or alcohol and water, the sanding rotating speed is 300-1500r/min, the grain diameter of the sanding zirconium beads is 0.5-10 mm (the zirconium beads with single grain diameter or the zirconium beads with mixed grain diameter), and the mass of the zirconium beads is 20-30kg. In the sanding step, a dispersant and a surface modifier are added. The dispersant is at least one of sodium benzoate, polyester and sodium hexametaphosphate, and the dosage of the dispersant is 0.3-2wt% of the mass of the third filler. Surface modificationThe agent is at least one of titanate, aluminate and silane coupling agent, and the dosage of the surface modifier is 0.5-3wt% of the inorganic powder. The third filler with the particle size of 200nm-5 mu m is prepared by the process.

(2) Preparing the surface treatment filler. The first filler is Si and the second filler is Si. And mixing the first filler, the flaky filler and peroxide, and then drying the mixture at low temperature by airflow to obtain the first filler and the second filler which are subjected to surface treatment, wherein the airflow drying temperature is not higher than the decomposition temperature of the peroxide.

(3) Mixing materials: and (3) compounding the third filler prepared in the step (1) and the surface treatment filler prepared in the step (2) to obtain an inorganic filler, and proportionally adding 50-90 parts by weight of the inorganic filler, 5-45 parts by weight of organic resin and 0.1-1 part by weight of an auxiliary agent into a roller filled with zirconium beads for ball milling and blending. Based on the total mass of the mixed materials, the content of the third filler is 65 parts by weight, the content of the first filler is 7 parts by weight, and the content of the second filler is 8 parts by weight. The ball milling time is 0.5-8h, and the ball milling rotating speed is 200-1000r/min.

(4) Banburying and granulating: and banburying and granulating the uniformly blended ingredients of the ball mill. Wherein the banburying temperature range is 150-350 ℃, the banburying pressure is less than 0.01MPa, or the whole process is protected by nitrogen. Banburying time is 0.5-6h, banburying rotation speed is 5-100r/min, and extrusion granulation is carried out after banburying is finished.

(5) Injection molding: and (3) carrying out injection molding on the granules obtained by banburying to form a designed shape. Wherein the injection nozzle temperature is 200-350 ℃, the injection pressure is 80-120Mpa, the injection speed is 50-95%, the mold temperature is 100-260 ℃, the pressure maintaining pressure is 30-100Mpa, and the pressure maintaining time is 5-50s.

(6) Warm isostatic pressing: and (4) carrying out vacuum sealing on the injection molding blank body, and carrying out warm isostatic pressing treatment. Wherein the temperature is 80-300 ℃, the glass transition temperature of the organic resin is required to be higher, and the working pressure can be 50-500MPa.

(7) And (4) heat treatment strengthening. The heat treatment temperature is 100-350 ℃, and the heat treatment time is 6-36h. The comprehensive heat conductivity coefficient of the shell assembly after heat treatment reaches 2.3-7.2W/(m.K), is much higher than that of plastic and is equivalent to that of ceramic.

Example 2

The other conditions were the same as in example 1 except that, in the step (2), the first filler was Al ₂ O ₃ The second filler is TiO ₂ 。

The comprehensive heat conductivity coefficient of the shell assembly after heat treatment reaches 1.7-5.5W/(m.K), which is much higher than that of plastic and is equivalent to that of ceramic.

Example 3

The other conditions were the same as in example 1 except that, after the step (7), the following steps were further included:

(8) And (6) polishing. And grinding and polishing the heat-treated sample. And removing the surface layer by rough polishing, wherein the removal amount of the rough polishing is 50-500 mu m, repairing the defects of the rough polishing by middle polishing, and finally performing fine polishing. So that the surface of the shell component achieves the effect of a ceramic mirror surface and luster. Wherein the surface roughness of the material after the fine polishing can be 0.02-0.05, which is equivalent to the surface roughness of the mirror surface ceramic after the polishing. Meanwhile, due to the orderly arrangement of the high-thermal-conductivity rod-shaped filler and the high-refraction sheet-shaped filler on the surface, the glossiness of the polished surface of the shell component at 20 degrees, 60 degrees and 80 degrees is equivalent to the glossiness of the polished surface of the ceramic at different angles.

(9) And (6) surface treatment. Plasma treatment is combined with micro-etching treatment.

Plasma treatment: and (3) under the protection of inert gases such as argon and nitrogen or under the vacuum condition (the vacuum pressure is less than 100 mt), treating the surface of the shell assembly obtained in the step (8) by using plasma, wherein the power of the plasma treatment is 150-500 watts, and the time of the plasma treatment is 5-60s (compared with the shell assembly before treatment, the surface of the shell assembly after the plasma treatment has 20 degrees, 60 degrees and 80 degrees of glossiness which is equivalent to that before the treatment, and the friction coefficient is reduced from 0.061-0.12).

Microetching treatment: firstly, weak acid solution such as citric acid or acetic acid with the mass concentration of 0.1-1% is prepared, then the solution is frozen to the temperature of 5-10 ℃, the shell assembly is directly soaked into the solution for 5-30s at the temperature, then the shell assembly is cleaned in water, the surface roughness of the shell assembly is kept between 0.02 and 0.06 after micro-etching, and the surface water drop angle is reduced to 20-70 degrees from 60-100 degrees before treatment.

Example 4

The other conditions were the same as those of example 2 except that, after step (7), step (8) polishing and step (9) surface treatment were further included, and the conditions of step (8) polishing and step (9) surface treatment were the same as those of example 3.

Example 5

The other conditions were the same as in example 2 except that, after step (7), step (8) polishing and step (9) surface treatment were further included, and the conditions for step (8) polishing were the same as those for polishing in example 3 and the conditions for step (9) surface treatment were different from those in example 3. The surface treatment steps of this embodiment are specifically:

(9) Film coating: depositing a zirconia ceramic material layer with the thickness of 10-30nm on the surface of the shell component by an ALD (atomic layer deposition) process, so that the surface energy, the surface hydrophilicity and hydrophobicity and the surface friction coefficient of the shell component are consistent with those of zirconia ceramic, wherein the ALD deposition precursor is trimethylzirconium, the reaction pressure is 0.1-10mbar, the reaction temperature is 50-500 ℃, and the reaction rate is 5-20nm/h.

The housing assemblies obtained in examples 3-5 were tested for their performance and compared to the performance parameters of PPS resin (pyridinium propane sulfonate) and zirconia ceramic, as shown in table 1 below.

TABLE 1

Note: pencil hardness test standard: GB/T6739-1996.

Falling ball impact test standard: the samples were flat sheets of 150 x 73 x 0.8 mm; the flat sample is supported on a jig (four sides are respectively provided with 3mm supports, the middle part is suspended), a 32g stainless steel ball is used for freely falling to the surface of the sample to be detected from a certain height, the four corners and the center of the sample have five points, and each point is detected for 5 times until the sample is broken.

As can be seen from table 1, the hardness, the glossiness, the thermal conductivity, the hydrophilicity and hydrophobicity, the friction coefficient, and the roughness of the shell assembly prepared by the method are equivalent to the performance parameters corresponding to ceramics, so that the shell assembly has the visual effect and the tactile effect similar to ceramics, has high ceramic texture, greatly improves the appearance expressive force of the shell assembly, and improves the visual effect of the shell assembly.

The embodiments of the present application have been described in detail, but the present application is not limited to the details of the above embodiments, and various simple modifications can be made to the technical solution of the present application within the technical idea of the present application, and the simple modifications belong to the protection scope of the present application. It should be noted that the various features described in the foregoing embodiments may be combined in any suitable manner without contradiction.

In the description of the present specification, reference to the description of "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

While embodiments of the present application have been shown and described above, it will be understood that the above embodiments are exemplary and should not be construed as limiting the present application and that changes, modifications, substitutions and alterations in the above embodiments may be made by those of ordinary skill in the art within the scope of the present application.

Claims

1. A method of making a housing assembly having a ceramic appearance, the method comprising:

mixing inorganic filler, organic resin and an auxiliary agent to form a mixed material;

banburying and granulating the mixed material to form granules;

performing injection molding on the granules to form a blank body;

carrying out warm isostatic pressing treatment on the blank;

carrying out heat treatment on the blank subjected to the warm isostatic pressing treatment to obtain a shell assembly;

wherein the inorganic filler comprises a first filler, a second filler, a third filler, and a peroxide;

the first filler is a rod-shaped filler and comprises Si and Al ₂ O ₃ 、AlN、ZrO ₂ 、Si ₃ N ₄ At least one of SiC;

the second filler is a flaky filler and comprises Si and TiO ₂ 、ZrO ₂ At least one of;

the temperature of the heat treatment is 100-350 ℃;

the rod-shaped filler is formed by a high heat conduction material, and the sheet-shaped filler is formed by a high refraction material;

forming the inorganic filler includes: mixing the peroxide with the first filler and the second filler, and then mixing the third filler with the first filler, the second filler and the peroxide to obtain the inorganic filler;

the peroxide comprises at least one of ammonium persulfate, potassium persulfate, hydrogen peroxide and benzoyl peroxide;

the ratio of the peroxide to the sum of the masses of the first filler and the second filler is (1-3): 100.

2. the method of claim 1,

the particle size of the third filler is 200nm-5 mu m;

the third filler includes Al ₂ O ₃ 、ZrO ₂ And SiC.

3. A method according to claim 1, characterized in that the inorganic filler is contained in an amount of 50-90 parts by weight, the third filler is contained in an amount of 50-85 parts by weight, the sum of the amounts of the first filler, the second filler and the peroxide is 5-30 parts by weight, the organic resin is contained in an amount of 5-45 parts by weight, and the auxiliary agent is contained in an amount of 0.1-1 part by weight, based on the total mass of the compounded material;

the organic resin comprises at least one of pyridinium propane sulfonate, polycarbonate, polyamide and polymethyl methacrylate.

4. The method of claim 1, wherein the injection molding is carried out at a nozzle temperature of 200-350 ℃, an injection pressure of 80-120Mpa, an injection speed of 50-95%, a mold temperature of 100-260 ℃, a holding pressure of 30-100Mpa, and a holding time of 5-50s.

5. The method according to claim 1, wherein the temperature of the warm isostatic pressing treatment is higher than the glass transition temperature of the organic resin and the working pressure is 50-500MPa.

6. The method according to claim 1, wherein the heat treatment time is 6 to 36 hours.

7. The method of claim 1, wherein after the heat treating, the method further comprises: and polishing the shell assembly.

8. The method of claim 7, wherein after the polishing process, the method further comprises: performing surface treatment on the shell assembly;

the surface treatment comprises any one of the following modes:

carrying out plasma treatment on the shell assembly, and then carrying out microetching treatment;

or coating the shell assembly with a film.

9. The method of claim 8, wherein the plasma processing comprises: treating a surface of the housing assembly with plasma;

the power of the plasma is 150-500 watts, and the processing time of the plasma is 5-60s;

the plasma treatment is carried out under the protection of inert gas or under vacuum condition.

10. The method of claim 8, wherein the microetching process comprises: soaking the shell assembly into a weak acid solution to react;

the weak acid comprises at least one of citric acid and acetic acid, and the mass concentration of the weak acid solution is 0.1-1%;

the reaction temperature of the microetching treatment is 5-10 ℃, and the reaction time of the microetching treatment is 5-30s.

11. The method of claim 8, wherein the coating comprises: depositing a ceramic material layer on the surface of the shell component;

the thickness of the ceramic material layer is 10-30nm;

the deposition method is an atomic layer deposition method, the ceramic material is at least one of alumina and zirconia, the deposited precursor comprises at least one of trimethylaluminum and trimethylzirconium, the deposition reaction pressure is 0.1-10mbar, the deposition reaction temperature is 50-500 ℃, and the deposition reaction rate is 5-20nm/h.

12. The method of claim 1, wherein after the heat treating, the method further comprises: introducing an organic olefin containing a double bond to the surface of the housing component to form a permeable layer;

the method of forming the transparent layer includes ultraviolet irradiation or plasma excitation.

13. A housing component having a ceramic appearance, wherein the housing component is prepared by the method of any one of claims 1 to 12.

14. An electronic device, characterized in that the electronic device comprises: the display screen assembly, the mainboard and the shell assembly;

the housing component is the ceramic appearing housing component of claim 13;

the display screen assembly is connected with the shell assembly, and an installation space is defined between the display screen assembly and the shell assembly;

the mainboard is arranged in the installation space and is electrically connected with the display screen assembly.