CN113507805A

CN113507805A - Shell, preparation method thereof and electronic equipment

Info

Publication number: CN113507805A
Application number: CN202110769358.0A
Authority: CN
Inventors: 张世龙; 滕双双
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2021-10-15
Anticipated expiration: 2041-07-07
Also published as: CN113507805B

Abstract

The application provides a shell, a preparation method thereof and electronic equipment. The housing includes: the shell body comprises raw material components including ceramic powder and an adhesive; the adhesive comprises polyvinyl butyral glue. The embodiment of the application provides a shell, and it has light, lower processing cost, in addition, can also have higher hardness, better glossiness and reflection of light rate.

Description

Shell, preparation method thereof and electronic equipment

Technical Field

The application relates to the field of electronics, in particular to a shell, a preparation method of the shell and electronic equipment.

Background

Ceramics have a warm and moist hand feeling and a high gloss texture, and therefore, are often used as exterior structural members of high-end electronic device housings, middle frames, decorative parts, and the like. However, the ceramic has a high density, severe processing conditions and high processing cost, so that the application is greatly limited.

Disclosure of Invention

In view of the above problems, embodiments of the present application provide a housing, which has a lighter weight and a lower processing cost, and in addition, can also have a higher hardness, a better gloss and a better light reflection rate.

The embodiment of the application provides a casing, it includes:

the shell body comprises raw material components including ceramic powder and an adhesive; the adhesive comprises polyvinyl butyral glue.

In addition, the embodiment of the application also provides a preparation method of the shell, the shell comprises a shell body, and the method comprises the following steps:

mixing the raw material components of the shell body to form slurry;

carrying out tape casting on the slurry to prepare a green body;

cold isostatic pressing the green body; and

and carrying out heat treatment to enable the adhesive to have polymerization reaction, so as to obtain the shell body.

In addition, an embodiment of the present application further provides an electronic device, which includes:

the shell assembly provided by the embodiment of the application is provided with an accommodating space;

a display component for displaying; and

and the circuit board assembly is arranged in the accommodating space, is electrically connected with the display assembly and is used for controlling the display assembly to display.

The shell comprises a shell body, wherein raw material components of the shell body comprise ceramic powder and an adhesive; the adhesive comprises polyvinyl butyral glue. Therefore, the prepared shell has lighter weight and lower processing cost. In addition, adopt the curtain coating mode shaping, can obtain the casing body that ceramic powder weight content exceeds 90%, compare in the casing that adopts thermoplastic resin and ceramic powder injection moulding to make, this application can make the casing that has higher hardness, better glossiness and reflection of light rate. Moreover, the raw material components of the shell body comprise ceramic powder and polyvinyl butyral glue, the viscosity of the polyvinyl butyral glue is low, so that the ceramic powder and the polyvinyl butyral glue have more uniform dispersibility when being mixed, and when the weight content of the ceramic powder is the same, compared with the shell body prepared by injection molding, the shell body prepared by the method has better hardness, glossiness and light reflection rate.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a housing according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a housing according to another embodiment of the present application.

Fig. 3 is a schematic flow chart illustrating a process for manufacturing a housing according to an embodiment of the present application.

Fig. 4 is a schematic flow chart illustrating the preparation of a housing according to another embodiment of the present application.

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

Fig. 6 is a circuit block diagram of an electronic device according to an embodiment of the present application.

Description of reference numerals:

100-shell 50-shield

10-case body 400-electronic device

101-accommodation space 410-display component

11-backplane 430-circuit board assembly

13-side panel 431-processor

30-hardened layer 433-memory

Detailed Description

In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first," "second," and the like in the description and claims of the present application and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

It should be noted that, for convenience of description, like reference numerals denote like parts in the embodiments of the present application, and a detailed description of the like parts is omitted in different embodiments for the sake of brevity.

Ceramics have a warm and moist hand feeling and a high gloss texture, and therefore, are often used as exterior structural members of high-end electronic device housings, middle frames, decorative parts, and the like. However, the ceramic has high density, the manufactured electronic device appearance structural member is heavy, the pencil has high hardness, is easy to crack and has high processing difficulty, and in addition, the processing cost of the ceramic is high, so that the application of the ceramic is greatly limited. In order to improve the performance and cost of ceramics, in the related art, a thermoplastic resin is mixed with ceramic powder (inorganic powder) and is subjected to injection molding to prepare a shell of an electronic device, however, when the content of the ceramic powder is over 90% by weight, the thermoplastic resin/ceramic powder formed by mixing is poor in fluidity, large in resistance in the injection molding process and obvious in flow mark. Therefore, the content of the ceramic powder is generally less than 90% during injection molding, however, when the content of the ceramic powder is less than 90%, the hardness of the housing of the electronic device is low, the wear resistance is poor, and the life of the housing of the electronic device is reduced.

Referring to fig. 1, an embodiment of the present application provides a housing 100, which includes: the shell comprises a shell body 10, wherein raw material components of the shell body 10 comprise ceramic powder and an adhesive; the adhesive comprises polyvinyl butyral glue.

Alternatively, the housing 100 of the present application may be an outer case, a middle frame, a decoration, and the like of an electronic device. The housing 100 of the embodiment of the present application may have a 2D structure, a 2.5D structure, a 3D structure, or the like. As shown in fig. 1, the housing 100 may optionally include a bottom plate 11 and a side plate 13 connected to the bottom plate 11 in a bent manner. The bottom plate 11 and the side plate 13 enclose an accommodating space 101. In some embodiments, the bottom plate 11 and the side plate 13 are a unitary structure, and in other embodiments, the bottom plate 11 and the side plate 13 are formed separately and then connected together. In a specific embodiment, the bottom plate 11 is a rear cover of the electronic device, and the side plate 13 is a middle frame of the electronic device.

The shell 100 of the embodiment of the application comprises a shell body 10, wherein raw material components of the shell body 10 comprise ceramic powder and an adhesive; the adhesive comprises polyvinyl butyral glue. Thereby resulting in a lighter weight and lower manufacturing cost for the housing 100. In addition, by adopting the tape casting method, the shell body 10 with the weight content of the ceramic powder exceeding 90% can be obtained, and compared with the shell 100 which is prepared by adopting the thermoplastic resin and the ceramic powder through injection molding, the shell 100 with higher hardness, better glossiness and light reflection rate can be prepared. Moreover, the raw material components of the housing body 10 of the present application include ceramic powder and polyvinyl butyral glue, and the polyvinyl butyral glue has a lower viscosity, so that when the ceramic powder is mixed with the polyvinyl butyral glue, the ceramic powder has more uniform dispersibility, and when the weight content of the ceramic powder is the same, compared with the housing body 10 prepared by injection molding, the housing body 10 prepared by the method of the present application has better hardness, glossiness and light reflection rate.

Optionally, the thickness of the housing body 10 is 0.3mm to 2 mm; specifically, the thickness of the case body 10 may be, but is not limited to, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, and the like. When the housing body 10 is too thin, the supporting and protecting functions cannot be well performed, the mechanical strength cannot well meet the requirements of the electronic device housing 100, and when the housing body 10 is too thick, the weight of the electronic device is increased, the hand feeling of the electronic device is affected, and the user experience is not good.

Optionally, the surface roughness of the case body 10 is ra0.02 to ra0.08, and specifically, may be, but not limited to, ra0.02, ra0.03, ra0.04, ra0.05, ra0.06, ra0.07, ra0.08, and the like. If the roughness is too large, the ceramic texture of the shell 100 is affected, and if the roughness is too small, the process requirements are too strict, and the preparation cost is high.

In some embodiments, the weight ratio of the ceramic powder to the binder is 3:2 to 18: 1; specifically, it may be, but not limited to, 3:2, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18: 1. Further, the weight ratio of the ceramic powder to the binder is 7:1 to 18:1, and specifically, may be, but not limited to, 6:1, 7:1, 8:1, 9:1, 10:1, 12:1, 14:1, 16:1, 18:1, and the like. When the weight ratio of the ceramic powder to the binder is within this range, the prepared shell 100 has better hand feeling, higher hardness, better glossiness and light reflection rate. Furthermore, the weight ratio of the ceramic powder to the binder is 9:1 to 18:1, so that the shell 100 has a hand feeling, hardness, gloss and light reflection rate closer to those of a pure ceramic piece, and has lower processing conditions and density.

Optionally, the ceramic powder includes one or more of zirconia, alumina, silica, titania, silicon carbide, silicon nitride, silicon, magnesia, beryllium oxide, vanadium pentoxide, diboron trioxide, spinel, calcium oxide, mullite, and barium titanate. Optionally, the ceramic powder has a particle size of 20nm to 1000 nm; specifically, it may be, but not limited to, 20nm, 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 1000nm, etc. When the particle size of the ceramic powder is too large, the volume ratio of the ceramic powder is small, so that the hardness of the prepared shell body 10 is low, and when the particle size of the ceramic powder is too small, the ceramic powder particles are easy to agglomerate and are not well dispersed, and pits are easy to be generated on the surface of the shell body 10 during subsequent polishing, so that the appearance and the texture of the shell 100 are affected.

Optionally, the adhesive further comprises one or more of polyurethane glue, epoxy glue, acrylic glue. The crosslinking degree of the polymer after the polyurethane glue, the epoxy resin glue and the acrylic resin glue are heated and cured is higher than that of the polymer after the polyvinyl butyral glue is cured, so that the prepared shell 100 has higher hardness.

In some embodiments, the adhesive comprises a polyvinyl butyral glue and a polyurethane glue. In still other embodiments, the adhesive comprises a polyvinyl butyral glue and an epoxy glue. In still other embodiments, the adhesive comprises a polyvinyl butyral glue and an acrylic glue. In still other embodiments, the adhesive includes polyvinyl butyral glue, polyurethane glue, epoxy glue, and acrylic glue. Optionally, the polyvinyl butyral glue is present in an amount of 50% to 80% by total weight of the adhesive, and in particular, but not limited to, 50%, 55%, 60%, 65%, 70%, 75%, 80%. When the content of the polyvinyl butyral glue is too small, the viscosity of the adhesive is higher, and the dispersion performance of the mixture of the ceramic powder and the adhesive is influenced.

In some embodiments, the raw material components of the housing body 10 of the embodiments of the present application further include a surface modifier, a colorant, a first dispersant, a second dispersant, an antifoaming agent, a plasticizer, and a solvent. Alternatively, before the housing body 10 is molded (a green body is prepared), the ceramic powder is uniformly mixed with the surface modifier, the coloring material, and the first dispersant, and then mixed with the second dispersant, the defoaming agent, the plasticizer, and the solvent to prepare a slurry. Thus, the ceramic powder can be more uniformly dispersed in the slurry, which is beneficial to improving the mechanical property of the shell body 10.

Alternatively, the surface modifier may be one or more of a silane coupling agent, ammonium citrate, polyacrylic acid, ammonium polymethacrylate, triethanolammonium. The surface modifier is used for modifying the ceramic powder, increasing the compatibility between the ceramic powder and the adhesive, improving the binding force between the ceramic powder and the adhesive, enabling the ceramic powder and the adhesive to be mixed more uniformly, and enabling the mixed system to be more stable, thereby improving the mechanical performance of the shell body 10. Optionally, the content of the surface modifier is 0.1 to 3 percent of the weight of the ceramic powder; specifically, it may be, but not limited to, 0.1%, 0.5%, 0.8%, 1.0%, 1.5%, 1.8%, 2.0%, 2.3%, 2.8%, 3.0%, etc. When the content of the surface modifier is less than 0.1%, the modification of the ceramic powder is incomplete, in other words, a part of the ceramic powder is not modified, which affects the binding force between the ceramic powder and the adhesive, and when the content of the surface modifier is more than 3%, excessive surface modifier molecules are deposited on the surface of the ceramic powder, so that the obtained ceramic powder is easy to agglomerate and is not easy to be uniformly dispersed in the adhesive, which is not beneficial to improving the mechanical performance of the shell body 10.

Alternatively, the coloring material may be an organic coloring material or an inorganic coloring material. The colorant is used to make the housing body 10 have a color pattern or color, so that the housing 100 has a color pattern or color, such as a pattern and color of a blue-and-white porcelain. By controlling the color and the ratio of the colorant, the housing body 10 can present different appearance effects, so that the housing 100 presents different appearance effects. Alternatively, the organic coloring material may be, but is not limited to, azo pigments, phthalocyanine pigments, and the like. The content of the organic coloring material is 1% to 5% by weight of the ceramic powder, and specifically, may be, but not limited to, 1%, 2%, 3%, 4%, 5%, and the like. Alternatively, the inorganic colorant may be, but is not limited to, iron oxide, cobalt oxide, manganese oxide, carbon black, and the like. The content of the inorganic coloring material is 3% to 20% by weight of the ceramic powder, and specifically, may be, but not limited to, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, and the like.

Alternatively, the first dispersant may be one or more of polyvinyl alcohol (PVA), polyethylene glycol (PEG), stearic acid, ammonium stearate. The first dispersing agent is used for improving the dispersing performance of the ceramic powder, improving the dispersibility of the ceramic powder in the adhesive, enabling the ceramic powder and the adhesive to be mixed more uniformly, and further enabling the prepared shell body 10 to have better mechanical performance. Alternatively, the content of the first dispersant is 0.1% to 1% by weight of the ceramic powder, and specifically, may be, but not limited to, 0.1%, 0.3%, 0.5%, 0.8%, 1.0%, and the like. When the content of the first dispersing agent is less than 0.1%, the first dispersing agent cannot wrap all ceramic powder particles, and the improvement on the dispersibility of the ceramic powder is small; when the content of the first dispersant is greater than 1%, too many molecules of the first dispersant are deposited on the surface of the ceramic powder, so that the obtained ceramic powder is easy to agglomerate and is not easy to be uniformly dispersed in the adhesive, and the improvement of the mechanical property of the shell body 10 is not facilitated.

Optionally, the second dispersant may be one or more of caprylic acid, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, castor oil. The second dispersant is used for enabling the ceramic powder to be dispersed in the adhesive more uniformly, and the mixed slurry is more stable. Alternatively, the content of the second dispersant may be 0.3% to 2% by weight of the total weight of the ceramic powder and the binder, and specifically, may be, but is not limited to, 0.3%, 0.5%, 1%, 1.5%, 2%, and the like.

Alternatively, the anti-foaming agent may be one or both of isobutanol, ethylene glycol. The defoaming agent is used for eliminating bubbles in the mixed slurry of the ceramic powder and the adhesive and preventing excessive bubbles from being generated in the slurry and influencing the mechanical performance of the prepared shell body 10. Alternatively, the content of the defoaming agent may be 0.1% to 1% of the total weight of the ceramic powder and the binder, and specifically, may be, but is not limited to, 0.1%, 0.3%, 0.5%, 0.8%, 1%, and the like, the content of the defoaming agent is too low to perform a defoaming function, the content of the defoaming agent is too high, the viscosity of the slurry is reduced, and the green body is not easily formed.

Alternatively, the plasticizer may be one or more of dioctyl phthalate (DOP), dibutyl sebacate (DBS) and Butyl Benzyl Phthalate (BBP). The plasticizer is used for increasing the plasticity of the adhesive and the fluidity of the slurry after the ceramic powder and the adhesive are mixed, so that the slurry can be better cast to form a green body. Alternatively, the content of the plasticizer may be 1% to 10% of the total weight of the ceramic powder and the binder, and specifically, may be, but is not limited to, 1%, 2%, 3%, 4%, 5%, 6%, 8%, 10%, etc., and the content of the plasticizer is too low, the casting property of the slurry is poor, and the content of the plasticizer is too high, which reduces the hardness of the prepared shell body.

Alternatively, the solvent may be one or more of ethanol, xylene, and the like. The solvent is used to dissolve a binder, a defoaming agent, a dispersant (a first dispersant and a second dispersant), a plasticizer, and the like. The content of the solvent may be 30% to 55% of the total weight of the ceramic powder and the binder, and specifically, may be, but is not limited to, 30%, 35%, 40%, 45%, 50%, 55%, and the like, and the content of the solvent is too small, the dispersibility of each component is not good during ball milling, and the content of the solvent is too large, and the solvent is not easily volatilized during tape casting, which affects the mechanical properties of the prepared shell body.

Referring to fig. 2, in some embodiments, the housing 100 of the embodiments of the present application further includes: the hardened layer 30 is disposed on the surface of the housing body 10, and the hardened layer 30 is used for improving the hardness and the wear resistance of the housing body 10; and an protective layer 50, the protective layer 50 set up in the sclerosis layer 30 is kept away from one side of casing body 10, the protective layer 50 is used for antifouling, preventing the fingerprint to improve the user experience of casing 100.

Optionally, the raw material component of the hardened layer 30 is one or more of graphite, alumina, zirconia, silica, chromium nitride, and titanium nitride. Specifically, the surface of the housing body 10 may be coated with the hardened layer 30 by means of sputtering vacuum plating or evaporation plating. Alternatively, the thickness of the hardened layer 30 is 500nm to 3 μm, and specifically, may be, but is not limited to, 500nm, 600nm, 700nm, 800nm, 1 μm, 2 μm, 3 μm, and the like. When the thickness of the hardened layer 30 is too thin, the abrasion resistance effect is not exerted, and when the thickness of the hardened layer 30 is too thick, the hardened layer 30 is easily cracked, resulting in the falling of the hardened layer.

In some embodiments, the raw material component of the protective layer 50 may include, but is not limited to, one or more of perfluoropolyether, perfluoropolyether derivatives, and the like, and the protective layer 50 is formed by evaporating a glue solution composed of the raw material component of the protective layer 50 on the surface of the case body 10. The perfluoropolyether and the perfluoropolyether derivative have excellent fingerprint resistance and can play a good role in fingerprint resistance and stain resistance.

In some embodiments, the water contact angle of the protective layer 50 is greater than 105 °, specifically, may be, but is not limited to, 106 °, 110 °, 115 °, 120 °, 125 °, 130 °, 140 °, 150 °, etc., the greater the water contact angle, the better the protective layer 505030 has anti-fingerprint effect.

Optionally, the protective layer 50 is light transmissive, and the optical transmittance of the protective layer 50 is greater than or equal to 80%, and specifically, may be, but is not limited to, 80%, 82%, 85%, 88%, 90%, 92%, 95%, 96%, 97%, and the like. The protective layer 50 has a high light transmittance, so that the ceramic texture and grain color of the housing body 10 are not shielded, thereby affecting the appearance effect of the housing 100, and the protective layer 50 can also make the housing 100 have glaze texture.

Alternatively, the thickness of the protective layer 50 is 5nm to 20nm, and specifically, may be, but is not limited to, 5nm, 6nm, 8nm, 10nm, 12nm, 14nm, 16nm, 18nm, 20nm, and the like. If the thickness of the protective layer 50 is too thin, the antifouling and fingerprint-proof effects cannot be achieved, and if the thickness of the protective layer 50 is too thick, the manufacturing cost of the housing 100 is increased, and the hand feeling of the housing 100 is also affected.

Compared with the shell 100 prepared by injection molding of thermoplastic resin and ceramic powder, the shell 100 with higher ceramic powder content can be obtained, and the ceramic powder and the adhesive have better dispersibility, so that the prepared shell 100 can have higher hardness, better glossiness and light reflection rate. The casing 100 of the present application has been tested to have a pencil hardness of 4H to 7H, such as 4H, 5H, 6H, 7H, etc. The Vickers hardness of the housing 100 may be 300HV to 600HV, such as 300HV, 350HV, 400HV, 450HV, 500HV, 550HV, 600HV, etc. The housing 100 may have a gloss (60 ° test) of 140 to 160, for example, 140, 145, 150, 155, 160, etc. The light reflection rate (wavelength 550nm) of the housing 100 may be 10% to 12%, for example, 10%, 11%, 12%, or the like.

Referring to fig. 1 and fig. 3, an embodiment of the present application further provides a method for preparing a housing 100, where the housing 100 includes a housing body 10, and the method includes:

s201, mixing the raw material components of the shell body 10 to form slurry;

optionally, the mixing the raw material components of the housing body 10 to form a slurry includes:

s2011, modifying the ceramic powder to obtain modified powder; and

specifically, the ceramic powder, the surface modifier and the first dispersant are placed in a ball milling tank according to the weight ratio of the above embodiment, water and alumina balls or zirconia balls are added, wet ball milling is performed, and then drying is performed to obtain the modified powder. When the raw material components of the shell body 10 further include a pigment, the pigment is further added before ball milling. Optionally, the weight ratio of the raw materials (the total weight of the ceramic powder, the surface modifier, the first dispersant and the pigment) to the water and the spheres is 1 (1-3) to 0.5-1.

Optionally, the ball milling time is 12h to 48 h; specifically, it may be, but is not limited to, 12h, 15h, 18h, 20h, 24h, 28h, 32h, 36h, 40h, 44h, 48h, etc. If the ball milling time is too short, the ceramic powder is not dispersed and modified completely, and if the ball milling time is too long, the ceramic powder is not modified further, and the preparation cost is increased.

Alternatively, the drying may be spray dried in a drying tower, and the feed temperature may be from 70 ℃ to 80 ℃; the air inlet temperature is 130 ℃ to 160 ℃; the air exhaust temperature is 70-85 ℃; the temperature in the tower is 70-90 ℃; the negative pressure in the tower is 50pa to 150 pa. For example: controlling the feeding temperature in the drying tower to be 70 ℃; the air inlet temperature is 130 ℃; the air exhaust temperature is 75 ℃; the temperature in the tower is 90 ℃; the negative pressure in the tower is 150 pa.

S2012, mixing the modified powder, the binder and the solvent to obtain the slurry.

Optionally, after mixing the modified powder, the binder and the solvent, performing ball milling in a ball milling tank for 12 to 24 hours, and standing for 2 to 6 hours to obtain slurry. Optionally, when the raw material components of the housing body 10 further include a second dispersant, an antifoaming agent, and a plasticizer, the step of mixing further includes adding the second dispersant, the antifoaming agent, and the plasticizer.

S202, carrying out tape casting on the slurry to prepare a green body;

specifically, the slurry is introduced into a slurry box of a casting machine, and the slurry is leveled or scraped and dried to obtain a green body. Alternatively, the thickness of the green stock may be controlled by the gap between the belt and the doctor blade of the casting machine.

Optionally, the casting machine is dried in a gradual heating mode or in multiple temperature sections to gradually remove the solvent in the slurry, so as to prevent the solvent in the slurry from volatilizing too fast, and prevent the defects of pit points and the like on the surface of the prepared green blank. In a specific embodiment, after the slurry is scraped, the casting machine is dried and molded by adopting four temperature sections, wherein the four temperature sections comprise: the temperature of the first section molding is lower than that of the second section molding, the temperature of the second section molding is lower than that of the third section molding, and the temperature of the third section molding is lower than that of the fourth section molding. Alternatively, the temperature of the first stage molding is 30 ℃ to 55 ℃, and specifically, may be, but not limited to, 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃ and the like. The temperature of the second molding step is 40 ℃ to 60 ℃, and specifically, it may be, but not limited to, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃ or the like. The temperature for the third stage molding is 50 ℃ to 70 ℃, and specifically, it may be, but not limited to, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃ and the like. The temperature of the fourth stage molding is 60 ℃ to 80 ℃, and specifically, it may be, but not limited to, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃ or the like. Alternatively, the temperature of the temperature section may be gradually increased or may be a constant temperature along the conveying direction of the conveyor belt, and the application is not particularly limited.

Optionally, the conveying speed of the conveyor belt of the casting machine is 50mm/min to 500 mm/min; specifically, it may be, but not limited to, 50mm/min, 100mm/min, 200mm/min, 300mm/min, 400mm/min, 500 mm/min. When the conveying speed of the conveyor belt is too fast, the solvent in the slurry is not completely volatilized, and when the heat treatment is performed, holes are easily generated in the housing body 10, and pits are easily generated on the surface of the housing body 10, so that the conveying speed of the conveyor belt is not too fast.

In some embodiments, prior to said casting said slurry, said method further comprises: defoaming the slurry.

Optionally, the slurry is placed in a defoaming machine, stirred and defoamed under a negative pressure state. Alternatively, the negative pressure value may be-0.095 Mpa (in other words, the defoaming air pressure is 0.006Mpa), and the defoaming time may be, but is not limited to, 25min to 60min, and specifically, may be, but is not limited to, 25min, 30min, 35min, 40min, 45min, 50min, 55min, 60min, and the like. The bubble removal time is too short to remove bubbles in the slurry as much as possible, the bubble removal time is too long, there is a limit to the continued reduction of bubbles in the slurry, and the production cost is increased.

S203, carrying out cold isostatic pressing on the green blank; and

specifically, at normal temperature, the green body is placed in a mold, vacuum pumping is performed after vacuum bagging, and the green body is placed in a water pressure device for cold isostatic pressing so that the green body is more compact, the compactness of the prepared shell body 10 is stronger, and the hardness of the prepared shell body 10 is favorably improved.

Optionally, the cold isostatic pressure is from 150MPa to 250 MPa; specifically, it may be, but not limited to, 150MPa, 160MPa, 180MPa, 200MPa, 220MPa, 240MPa, 250MPa, etc. The pressure is too small, the improvement of the green compact is limited, the hardness of the prepared shell body 10 cannot be well improved, the pressure is too large, the requirement on equipment is high, but the green compact is basically stable, and the green compact cannot change too much.

Optionally, the time of cold isostatic pressing is from 10min to 60 min; specifically, it may be, but not limited to, 10min, 20min, 30min, 40min, 50min, 60min, etc. The time is too short, the improvement of the green compact is limited, the hardness of the prepared shell body 10 cannot be well improved, the time is too long, the production efficiency is affected, and the green compact is basically stable and cannot be changed too much.

S204, heat treatment is performed to obtain the housing body 10.

Optionally, the green body is placed in a jig with a certain self weight (e.g. 5Kg to 20Kg), and is subjected to heat treatment in an oven to polymerize the binder, and the temperature is reduced to obtain the shell body 10. After heat treatment, the adhesive is polymerized to generate high molecules to form a polymer network structure, so that the ceramic powder is bound in the polymer network structure. In addition, during heat treatment, the jig has a certain self weight, which can further prevent the deformation of the green body during the heat treatment, so that the shape of the manufactured shell body 10 is changed.

Optionally, the heat treatment is a staged heat treatment comprising: first stage heat treatment and second stage heat treatment; the temperature of the second stage heat treatment is higher than that of the first stage heat treatment. In other embodiments, only a single stage heat treatment may be used. By adopting the segmented heat treatment, the phenomenon that too much air bubbles are trapped inside the prepared shell body 10 to influence the appearance effect and the texture of the prepared shell 100 due to the fact that the reaction of the adhesive is too violent in the heat treatment process can be prevented, meanwhile, the reaction of the adhesive can be more complete, ceramic powder can be better bound in a polymer network, and the prepared shell body 10 has better mechanical property.

Optionally, the first stage heat treatment comprises: gradually heating to 130-160 ℃, and preserving the heat for 2-4 h at 130-160 ℃. Alternatively, the temperature of the first stage heat treatment may be, but is not limited to, 130 ℃, 135 ℃, 140 ℃, 145 ℃, 150 ℃, 155 ℃, 160 ℃, and the like. The gradual heating time is 0.5h to 1 h; specifically, it may be, but is not limited to, 0.5h, 0.8h, 1h, etc. Alternatively, the incubation time of 130 ℃ to 160 ℃ may be, but is not limited to, 2h, 2.5h, 3h, 3.5h, 4h, and the like. The heat treatment at 130-160 deg.c can make most of the adhesive produce polymerization reaction to form polymer network structure and the reaction is not too violent.

Optionally, the second stage heat treatment comprises: gradually heating to 180-250 deg.c and maintaining at 180-250 deg.c for 2-12 hr. Alternatively, the temperature of the second heat treatment may be, but is not limited to, 180 ℃, 190 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃, 250 ℃ and the like. The gradual heating time is 0.5h to 4 h; specifically, it may be, but not limited to, 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, etc. The holding time of 180 ℃ to 250 ℃ may be, but is not limited to, 2h, 4h, 6h, 8h, 10h, 12h, and the like. The second stage heat treatment may result in more complete polymerization of the binder, thereby resulting in a housing body 10 having a higher hardness.

In some embodiments, the method for preparing the housing 100 of the application further comprises, after the heat treatment: computer numerical control precision machining (CNC machining) is performed.

Optionally, the housing body 10 is CNC machined using a polycrystalline diamond cutter (diamond PCD milling cutter). Optionally, the spindle speed is 10000rpm to 25000 rpm; the single cutting amount is 0.01mm to 0.50 mm.

In some embodiments, the method of making the claimed housing 100 further comprises: and grinding and polishing.

Alternatively, the lapping polishing includes rough polishing and finish polishing, in other words, the rough polishing is performed first, and then the finish polishing is performed.

Optionally, the rough polishing may be processed using one or more of a sweep polisher, a double side grinder, a five axis polisher. The polishing disk can be one or more of pig hair, a buffing disk, damping cloth, a glue thread, a copper wire, a carpet and a pig hair/buffing composite material; the polishing assistant may be one or more of water-based diamond polishing liquid and oil-based diamond polishing liquid. Alternatively, the water-based diamond polishing liquid or the oil-based diamond polishing liquid may have a particle size of 0.5 μm to 20 μm; specifically, it may be, but not limited to, 0.5. mu.m, 1. mu.m, 3. mu.m, 5. mu.m, 7. mu.m, 10. mu.m, 12. mu.m, 15. mu.m, 18. mu.m, 20. mu.m, or the like. The mass concentration of the particle diameter of the water-based diamond polishing liquid or the oil-based diamond polishing liquid is 1 to 30%; specifically, it may be, but not limited to, 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, 28%, 30%, etc.

Alternatively, the finish polishing may be performed by one or both of a polisher and a double-side polisher. The polishing solution can be one or more of silicon oxide polishing solution and cerium oxide polishing solution. The particle size of the silicon oxide polishing solution or the cerium oxide polishing solution can be 50nm to 500 nm; specifically, it may be, but not limited to, 50nm, 80nm, 100nm, 120nm, 150nm, 180nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc. The mass concentration of the silicon oxide polishing solution or the cerium oxide polishing solution is 5 to 45 percent; specifically, it may be, but not limited to, 5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, 28%, 30%, 35%, 40%, 45%, etc.

According to the preparation method of the shell, the shell body 10 is prepared in a tape casting mode, so that the shell body 10 with the weight content of the ceramic powder exceeding 90% can be prepared, and the shell 100 with higher hardness, better glossiness and light reflection rate can be obtained. In addition, the adhesive has lower viscosity compared with the molten thermoplastic resin, the ceramic powder has more uniform dispersibility when being mixed with the adhesive, and when the weight content of the ceramic powder is the same, the shell 100 prepared by the method has better hardness, glossiness and light reflection rate compared with the shell 100 prepared by injection molding. Furthermore, prior to heat treatment, the green body is cold isostatically pressed, which causes the green body to be more densified, thereby resulting in a shell 100 having a higher hardness.

For features of the embodiment that are not described herein and are the same as those of the embodiment, please refer to the description of the corresponding portions of the embodiment, which is not repeated herein.

Referring to fig. 2 and 4, an embodiment of the present application further provides a method for manufacturing a housing 100, where the housing 100 includes a housing body 10; a hardened layer 30, wherein the hardened layer 30 is arranged on the surface of the shell body 10; the protective layer 50 is arranged on one side, far away from the shell body 10, of the hardened layer 30; the method comprises the following steps:

s301, mixing the raw material components of the shell body 10 to form slurry;

s302, carrying out tape casting on the slurry to obtain a green body;

s303, carrying out cold isostatic pressing on the green blank;

s304, performing heat treatment to obtain a shell body 10;

for detailed descriptions of steps S301 to S304, please refer to the description of the corresponding parts of the above embodiments, which is not repeated herein.

S305, forming a hardened layer 30 on the surface of the housing body 10; and

optionally, one or more of graphite, aluminum oxide, zirconium oxide, silicon oxide, chromium nitride and titanium nitride is used as a raw material, and a hardened layer 30 is plated on the surface of the shell body 10 by sputtering vacuum plating or evaporation plating, so that the hardness and the wear resistance of the shell body 10 are improved.

S306, forming a protective layer 50 on the surface of the hardened layer 30 far away from the shell body 10.

Optionally, one or more of perfluoropolyether, perfluoropolyether derivatives, etc. are used to deposit a protective layer 50 on the surface of the hardened layer 30 away from the housing body 10 to perform fingerprint and dirt resistance.

The housing 100 of the embodiment of the present application is further described below by way of specific embodiments.

EXAMPLE 1 tape casting

1) Modifying ceramic powder: putting alumina, silicon oxide, a silane coupling agent, PVA, PEG, ferric oxide, cobalt oxide and manganese oxide into a ball milling tank, carrying out wet ball milling (ball milling in water) for dispersing for 24 hours, and carrying out spray drying to obtain modified powder, wherein the weight ratio of the alumina to the silicon oxide is 5: 1; the weight of the silane coupling agent is 0.3 percent of the total weight of the alumina and the silica; the total weight of PVA and PEG is 0.2 percent of the total weight of alumina and silica, and the weight ratio of PVA to PEG is 1: 1; the iron oxide, the cobalt oxide and the manganese oxide account for 15 percent of the total weight of the aluminum oxide and the silicon oxide; the weight ratio of the iron oxide to the cobalt oxide to the manganese oxide is 3:1: 1.

2) Mixing modified powder, polyvinyl butyral (PVB) glue (adhesive), polyurethane glue (adhesive), polyvinylpyrrolidone (dispersant), isobutanol (defoamer), dioctyl phthalate (plasticizer) and ethanol (solvent), ball-milling in a ball-milling tank for 20h, and standing for 2h to obtain slurry; wherein the weight ratio of the modified powder to the adhesive (polyvinyl butyral glue and polyurethane glue) is 16: 3; the weight ratio of the polyvinyl butyral glue to the polyurethane glue is 8: 2; the weight of the polyvinylpyrrolidone is 0.6 percent of the total weight of the modified powder and the adhesive; the weight of the isobutanol is 0.1 percent of the total weight of the modified powder and the adhesive; the weight of the dioctyl phthalate is 4 percent of the total weight of the modified powder and the adhesive; the weight of the ethanol is 30 percent of the total weight of the modified powder and the adhesive.

3) Placing the slurry in a defoaming machine, and defoaming for 60min under negative pressure of-0.095 Mpa.

4) Carrying out tape casting to obtain a green body; wherein: the temperature of the first section of the casting machine is 35 ℃, the temperature of the second section is 40 ℃, the temperature of the third section is 60 ℃, the temperature of the fourth section is 75 ℃, the conveying speed of the conveying belt is 100mm/min, and the thickness of the green blank is 0.8 mm.

5) Performing cold isostatic pressing under 180MPa for 30 min.

6) Carrying out heat treatment: heating to 150 ℃ within 0.5 h; keeping the temperature at 150 ℃ for 2 h; heating to 200 deg.C in 0.5h, and maintaining at 200 deg.C for 6 h.

7) And carrying out CNC machining, grinding and polishing to obtain the shell.

Comparative example 1 injection Molding

2) Extruding and blending modified powder, polyphenylene sulfide (thermoplastic resin), polyvinylpyrrolidone (dispersant), isobutanol (defoamer) and dioctyl phthalate (plasticizer) to form granules; wherein the weight ratio of the modified powder to the polyphenylene sulfide is 16: 3; the weight ratio of the polyvinyl butyral glue to the polyurethane glue is 8: 2; the weight of the polyvinylpyrrolidone is 0.6 percent of the total weight of the modified powder and the polyphenylene sulfide; the weight of the isobutanol is 0.1 percent of the total weight of the modified powder and the polyphenylene sulfide; the weight of the dioctyl phthalate is 4 percent of the total weight of the modified powder and the polyphenylene sulfide.

3) The following temperature sections are adopted in an injection molding machine, and the temperature is gradually increased for injection molding: the first temperature range is 270 ℃ to 290 ℃, the second temperature range is 290 ℃ to 310 ℃, the third temperature range is 310 ℃ to 330 ℃, the fourth temperature range is 330 ℃ to 350 ℃, and the head temperature is 330 ℃ to 350 ℃; temperature of the die: 160 ℃; a housing assembly with a thickness of 0.8mm was obtained.

4) And carrying out CNC machining, grinding and polishing to obtain the shell.

The housing prepared in the above examples and comparative examples was tested for various properties by the following methods:

1) gloss test (60 ° test): the measurement was carried out using a gloss meter.

2) Reflectance test (wavelength 550 nm): the measurement was performed using an ultraviolet spectrophotometer.

3) And (3) testing pencil hardness: the test was carried out using GB/T6739-.

4) Vickers hardness: the test is carried out by GB/T4340.1-2009.

The test results are shown in table 1 below.

TABLE 1 Performance parameters of the casings of the examples and comparative examples

Performance parameter	Example 1	Comparative example 1
			Degree of gloss	150	120
Reflection rate	12％	8％
			Pencil hardness (H)	5H	2H
Vickers Hardness (HV)	450HV	55HV

As can be seen from table 1, when the content of the ceramic powder is the same, the housing prepared by using the components and the tape casting method of the embodiment of the present application has better glossiness and light reflection rate, and also has higher pencil hardness and vickers hardness, compared to the housing prepared by using the injection molding method.

Referring to fig. 5, an embodiment of the present application further provides an electronic device 400, which includes: in the housing 100 according to the embodiment of the present application, the housing 100 has an accommodating space 101; a display component 410 for displaying; and a circuit board assembly 430, wherein the circuit board assembly 430 is disposed in the accommodating space 101, electrically connected to the display assembly 410, and configured to control the display assembly 410 to display. Optionally, the display component 410 is further configured to enclose the accommodating space 101; in other words, the housing 100 and the display module 410 enclose a closed accommodating space 101.

The electronic device 400 of the embodiment of the present application may be, but is not limited to, a portable electronic device such as a mobile phone, a tablet, a notebook, a desktop, a smart band, a smart watch, an electronic reader, and a game console.

For a detailed description of the housing 100, please refer to the description of the corresponding parts of the above embodiments, which is not repeated herein.

Alternatively, the display module 410 may be, but is not limited to, one or more of a liquid crystal display module, a light emitting diode display module (LED display module), a micro light emitting diode display module (micro LED display module), a sub-millimeter light emitting diode display module (MiniLED display module), an organic light emitting diode display module (OLED display module), and the like.

Referring also to fig. 6, optionally, the circuit board assembly 430 may include a processor 431 and a memory 433. The processor 431 is electrically connected to the display component 410 and the memory 433, respectively. The processor 431 is configured to control the display component 410 to display, and the memory 433 is configured to store program codes required by the processor 431 to operate, program codes required by the display component 410 to be controlled, display contents of the display component 410, and the like.

Optionally, processor 431 includes one or more general-purpose processors 431, where general-purpose processor 431 may be any type of device capable of Processing electronic instructions, including a Central Processing Unit (CPU), a microprocessor, a microcontroller, a host processor, a controller, an ASIC, and so forth. Processor 431 is configured to execute various types of digitally stored instructions, such as software or firmware programs stored in memory 433, which enable the computing device to provide a wide variety of services.

Alternatively, the Memory 433 may include a Volatile Memory (Volatile Memory), such as a Random Access Memory (RAM); the Memory 433 may also include a Non-volatile Memory (NVM), such as a Read-Only Memory (ROM), a Flash Memory (FM), a Hard Disk (HDD), or a Solid-State Drive (SSD). The memory 433 may also include a combination of memories of the sort described above.

Reference herein to "an embodiment" or "an implementation" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present application and not for limiting, and although the present application is described in detail with reference to the above preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present application without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A housing, comprising:

2. The housing of claim 1, wherein a weight ratio of the ceramic powder to the binder is 3:2 to 18: 1.

3. The housing of claim 2, wherein the adhesive further comprises one or more of a polyurethane glue, an epoxy glue, an acrylic glue; the content of the polyvinyl butyral glue is 50-80% of the total weight of the adhesive.

4. The housing of claim 3, wherein the ceramic powder comprises one or more of zirconia, alumina, silica, titania, silicon carbide, silicon nitride, silicon, magnesia, beryllia, vanadium pentoxide, diboron trioxide, spinel, calcium oxide, mullite, barium titanate.

5. The housing of claim 4, wherein the raw material components of the housing body further comprise a surface modifier, a colorant, a first dispersant, a second dispersant, an antifoaming agent, and a plasticizer.

6. The housing according to any one of claims 1 to 5, further comprising:

the hardening layer is arranged on the surface of the shell body, and the raw material components of the hardening layer are one or more of graphite, aluminum oxide, zirconium oxide, silicon oxide, chromium nitride and titanium nitride; and

the inoxidizing coating, the inoxidizing coating set up in the sclerosis layer is kept away from one side of casing body, the luminousness of inoxidizing coating is more than or equal to 80%.

7. A method of making a housing, the housing comprising a housing body, the method comprising:

mixing the raw material components of the shell body to form slurry;

carrying out tape casting on the slurry to prepare a green body;

cold isostatic pressing the green body; and

and carrying out heat treatment to obtain the shell body.

8. The method of making a housing of claim 7, wherein the heat treatment is a staged heat treatment comprising: first stage heat treatment and second stage heat treatment; the temperature of the second stage heat treatment is higher than that of the first stage heat treatment.

9. The method of manufacturing a housing of claim 8, wherein the first stage heat treatment comprises: gradually heating to 130-160 ℃, and preserving heat for 2-4 h at 130-160 ℃; the second stage heat treatment comprises: gradually heating to 180-250 deg.c and maintaining at 180-250 deg.c for 2-12 hr.

10. The method of manufacturing a housing according to any one of claims 7 to 9, wherein the tape casting includes four temperature stage molding including first stage molding, second stage molding, third stage molding, and fourth stage molding; the temperature of the first section molding is 30-55 ℃, the temperature of the second section molding is 40-60 ℃, the temperature of the third section molding is 50-70 ℃, and the temperature of the fourth section molding is 60-80 ℃; the cold isostatic pressing pressure is 150MPa to 250 MPa.

11. An electronic device, comprising:

the housing assembly of any one of claims 1 to 6, having an accommodation space;

a display component for displaying; and