(19)
(11)EP 3 789 366 A1

(12)EUROPEAN PATENT APPLICATION

(43)Date of publication:
10.03.2021 Bulletin 2021/10

(21)Application number: 20150852.0

(22)Date of filing:  09.01.2020
(51)Int. Cl.: 
C04B 41/00  (2006.01)
C04B 41/87  (2006.01)
A45C 5/02  (2006.01)
H04M 1/02  (2006.01)
C04B 41/83  (2006.01)
C04B 37/00  (2006.01)
C04B 41/45  (2006.01)
C04B 41/89  (2006.01)
A45C 11/00  (2006.01)
C04B 41/52  (2006.01)
B29C 45/14  (2006.01)
(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
KH MA MD TN

(30)Priority: 06.09.2019 CN 201910843339

(71)Applicant: Beijing Xiaomi Mobile Software Co., Ltd.
Beijing 100085 (CN)

(72)Inventor:
  • WANG, Yukun
    Beijing, 100085 (CN)

(74)Representative: Gevers Patents 
Intellectual Property House Holidaystraat 5
1831 Diegem
1831 Diegem (BE)

  


(54)SHELL AND PROCESSING METHOD OF SHELL


(57) The present disclosure relates to a shell and a processing method of the shell, particularly to the need of weight loss of consumer electronics. The method includes: coating a sol prepared in advance on an inner surface of a ceramic shell prepared in advance (101); sintering the ceramic shell coated with the sol by using a sintering process, and forming a transition layer having nano-sized micro-pores on the inner surface of the ceramic shell (102). Therefore, excellent combination anchor points are provided for combination of the ceramic shell and a plastic part, the mechanical lock effect is formed, the bonding between the ceramic shell and the plastic part is improved and the purposes of reinforcing ceramic strength and reducing weight are achieved in a manner of injection molding or gluing of a composite fiberboard to obtain the finished product shell in a desired effect.




Description


[0001] The present application is based upon and claims priority to Chinese Patent Application No. 201910843339.0, filed on September 6, 2019, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD



[0002] The present disclosure relates to the technical field of terminals, and more particularly to, a shell and a processing method of the shell.

BACKGROUND



[0003] Smart phones have gained popularity in the last decade, and materials of shells of mobile phone have been changed dramatically, and are developed from plastics to new-generation materials represented by metallic glass. However, in a case that the differentiation of mobile phone hardware is not obvious, the innovation of materials has become one of the main ways for terminal manufacturers to solve the serious homogenization of the smart phones. Common materials of shells of mobile phone include plastics, metals, glass, ceramics, woods, leathers and so on. Their physical characteristics are not the same, therefore the look and feel of the manufactured mobile phones are different.

[0004] In a related art, considering that the ceramic has higher hardness than the glass, is more scratch-resistant and wear-resistant, unique in crystal clear impression, and low in interference on high-frequency signals, therefore, a ceramic shell based on the ceramic material is highly concerned by terminal manufacturers and users; however, since the ceramic are heavy in weight and high in cost, and a buckle is difficultly processed and connected with a middle frame inside the ceramics, the ceramics are hopefully thinned and compounded with plastic or fiber boards to reduce the weight of the shell.

SUMMARY



[0005] For solving the problem existing in the related art, embodiments of the present disclosure provide a shell and a processing method of the shell. The technical solution is as follows.

[0006] According to an aspect of the embodiments of the present disclosure, a processing method of a shell is provided, the processing method including:
a sol prepared in advance is coated on an inner surface of a ceramic shell prepared in advance.

[0007] The ceramic shell coated with the sol is sintered by using a sintering process, and a transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell;
the ceramic shell is connected with a plastic part through the transition layer to prepare a target shell.

[0008] The technical solutions provided by the embodiments of the present disclosure may have the following beneficial effects: in the technical solution, the sol is coated on the surface of the ceramic shell and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell by using a low-temperature sintering process. Therefore, mechanical anchor points are provided for combination of the ceramics and the plastic part, the mechanical lock effect is formed, the bonding between the ceramics and the plastic parts is improved. In addition, the process of connecting the ceramics and the plastic parts does not require special surface treatment on ceramic surfaces, thereby reducing the processing procedure of the ceramic shell, reducing the production energy consumption and being simple to operate. The technical solution may be applied to conventional engineering plastics or rubbers. The design space of ceramics and plastic material selection is greatly expanded; the transition layer does not affect the polish or glaze decoration of the outer surface of the ceramic shell.

[0009] In an embodiment, a component of the sol includes any of the following elements or a combination thereof: Al, Zr or Zn.

[0010] In an embodiment, a component of the ceramic shell includes any of the following materials or a combination thereof: aluminum oxide, zirconium oxide or zinc oxide.

[0011] In an embodiment, before coating the sol prepared in advance on an inner surface of the ceramic shell, the method further includes:
a sol precursor is added into water in several times, and a suspension-like liquid is obtained in a heating reflux manner, and the suspension-like liquid contains a hydrolyzed precipitate at a bottom of the suspension-like liquid.

[0012] A strong acid is added into the suspension-like liquid in several times, and clarified sol is obtained in the heating reflux manner.

[0013] In an embodiment, the process of coating the sol prepared in advance on the inner surface of the ceramic shell includes:
the sol prepared in advance is coated on the inner surface of the ceramic shell by using any of the following coating methods or a combination thereof: dip-coating, casting, spin-coating and spraying.

[0014] In an embodiment, the process of sintering the ceramic shell coated with the sol by using the sintering process includes:
the ceramic shell coated with the sol is kept in a dust-free environment for a preset time, and then placed in a sintering furnace for sintering treatment; herein, a sintering temperature ranges from 660 degrees centigrade to 850 degrees centigrade, and a heat preservation time is at least 1 hour.

[0015] In an embodiment, the process of connecting the ceramic shell and the plastic part through the transition layer to prepare the target shell includes:
the ceramic shell is connected with the plastic part through the transition layer by bonding or injection molding to prepare the target shell.

[0016] According to a second aspect of the embodiment of the present disclosure, a shell is provided. The shell is produced by using the steps of the method in the above first aspect, and the shell includes:
a ceramic shell and a plastic part, wherein a transition layer having nano-sized micro-pores is formed on an inner surface of the ceramic shell. The ceramic shell is connected with the plastic part through the transition layer.

[0017] In an embodiment, the ceramic shell is connected with the plastic part through the transition layer by bonding or injection molding.

[0018] It is to be understood that the above general descriptions and detailed descriptions below are only exemplary and explanatory and not intended to limit the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS



[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

FIG. 1 is a flow chart showing a processing method of a shell illustrated according to an exemplary embodiment.

FIG. 2 is a flow chart showing a processing method of a shell illustrated according to an exemplary embodiment.

FIG. 3 is a diagrammatic cross section showing a shell illustrated according to an exemplary embodiment.


DETAILED DESCRIPTION



[0020] Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same reference numeral in different drawings represents the same or similar elements unless otherwise represented. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the present disclosure. Instead, they are merely examples of apparatuses and methods consistent with aspects related to the present disclosure as recited in the appended claims.

[0021] In a related art, many manufacturers utilize ceramic materials to manufacture a mobile phone. However, since the ceramic surface is smooth after mold pressing and sintering, the surface tension is smaller than that of commonly used plastics, during bonding or injection molding, the ceramic surface is dependent on the electrochemical surface treatment to improve the surface bonding, and the bonding between the ceramic and the plastic parts is weak. Since the working procedure and production energy consumption are increased, the structural design of the ceramics on mobile phone products is limited to some extent.

[0022] For solving the above problem, the embodiments of the present disclosure provide a processing method of the shell. The method includes: coating a sol prepared in advance on an inner surface of a ceramic shell prepared in advance; sintering the ceramic shell coated with the sol by using a sintering process, and forming a transition layer having nano-sized micro-pores on the inner surface of the ceramic shell; connecting the ceramic shell and a plastic part through the transition layer to prepare a target shell. By adopting the technical solution provided by the embodiments of the present disclosure, the sol is coated on the surface of the ceramic shell and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell by using a low-temperature sintering process. Therefore, mechanical anchor points are provided for combination of the ceramic and the plastic part, the mechanical lock effect is formed, the bonding between the ceramic and the plastic part is improved. In addition, the process of connecting the ceramic and the plastic part does not require special surface treatment on the ceramic surfaces, thereby reducing the processing procedure of the ceramic shell, reducing the production energy consumption and being simple to operate. The technical solution may be applied to conventional engineering plastics or rubbers. The design space of ceramic and plastic material selection is greatly expanded; the transition layer does not affect the polish or glaze decoration of the outer surface of the ceramic shell. The target shell in the present disclosure may be applied to user equipment such as a mobile phone, a tablet computer or wearable equipment.

[0023] On the basis of the above analysis, the embodiments of the method of the present disclosure are introduced below.

[0024] FIG. 1 is a flow chart showing a processing method of a shell illustrated according to an exemplary embodiment. As shown in FIG. 1, the method includes the following steps 101-103.

[0025] In step 101, a sol prepared in advance is coated on an inner surface of a ceramic shell prepared in advance.

[0026] In an example, a component of the sol includes metal elements such as Al, Zr or Zn, and the sol contains a sol complex salt produced by hydrolysis of sol precursor. The component of the ceramic shell includes, but is not limited to, metal oxide ceramics such as aluminum oxide, zirconium oxide or zinc oxide. Optionally, in order to ensure good chemical compatibility and cross-section compounding property between the sol and the ceramic shell, the components of the sol and the ceramic shell generally contain the same metal element.

[0027] In an example, before the sol prepared in advance is coated on the inner surface of the ceramic shell prepared in advance, the sol needs to be prepared. A method for preparing the sol may include: adding the sol precursor into water in several times, and obtaining a suspension-like liquid in a heating reflux manner, and the suspension-like liquid contains a hydrolyzed precipitate at a bottom of the suspension-like liquid, herein the sol precursor includes a hydrolyzed basic salt precipitate containing the metal elements such as Al, Zr or Zn; and adding a certain amount of strong acid into the suspension-like liquid in several times and obtaining an uniformly clarified sol in the heating reflux manner. Optionally, the strong acid added into the suspension-like liquid is used as a sol agent, and the specific type of strong acid depends on the component of the sol precursor.

[0028] In an example, coating the sol prepared in advance on the inner surface of the ceramic shell includes: coating the sol prepared in advance on the inner surface of the ceramic shell by using any of the following coating methods or a combination thereof: dip-coating, casting, spin-coating and spraying.

[0029] In step 102, the ceramic shell coated with the sol is sintered by using a sintering process, and a transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell.

[0030] In an example, the ceramic shell coated with the sol is kept in a dust-free environment for a preset time, and then placed in a sintering furnace for sintering treatment; herein, a sintering temperature ranges from 660 degrees centigrade to 850 degrees centigrade, and a heat preservation time is at least 1 hour. Optionally, the sintering temperature is 780 degrees centigrade, the heat preservation time is 1 hour, the preset time is 4 hours and a temperature raise rate is 2 degrees centigrade/min. The sintering temperature is lower than the sintering temperature during manufacture of the ceramic shell.

[0031] In an example, the transition layer includes a mesoporous structure or a microporous structure. Since the components of the sol and the ceramic shell contain the same metal element, the ceramic shell and the transition layer are less prone to cracking or transition layer peeling caused by the difference in thermal expansion coefficient in a sintering procedure.

[0032] In step 103, the ceramic shell is connected with a plastic part through the transition layer to prepare a target shell.

[0033] In an example, the process of connecting the ceramic shell and the plastic part through the transition layer to prepare the target shell includes: connecting the ceramic shell and the plastic part through the transition layer by bonding or injection molding to prepare the target shell.

[0034] In an example, the material of the plastic part may include: plastics or rubbers such as polycarbonate (PC), polymethyl methacrylate (PMMA), acrylonitrile-butadiene-styrene copolymer (ABS), polyamide (PA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), nitrile rubber, or glass fiber/basalt fiber/carbon fiber composite board.

[0035] According to the technical solution provided by the embodiments of the present disclosure, the sol is coated on the surface of the ceramic shell and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell by using a low-temperature sintering process. Therefore, mechanical anchor points are provided for combination of the ceramics and the plastic part, the mechanical lock effect is formed, the bonding between the ceramic and the plastic part is improved. In addition, the process of connecting the ceramic and the plastic part does not require special surface treatment on the ceramic surfaces, thereby reducing the processing procedure of the ceramic shell, reducing the production energy consumption and being simple to operate. The technical solution may be applied to conventional engineering plastics or rubbers. The design space of ceramics and plastic material selection is greatly expanded; the transition layer does not affect the polish or glaze decoration of the outer surface of the ceramic shell.

[0036] FIG. 2 is a flow chart showing a processing method of a shell illustrated according to an exemplary embodiment. As shown in FIG. 2, on the basis of the embodiment shown in FIG. 1, the processing method of the shell involved in the present disclosure includes the following steps 201-205.

[0037] In step 201, a sol precursor is added into water in several times, and a suspension-like liquid is obtained in a heating reflux manner, and the suspension-like liquid contains a hydrolyzed precipitate at a bottom of the suspension-like liquid.

[0038] In an example, the sol precursor contains a hydrolyzed basic salt precipitate containing metal elements such as Al, Zr or Zn. The component of the ceramic shell includes, but is not limited to, metal oxide ceramics such as aluminum oxide, zirconium oxide or zinc oxide; the components of the sol and the ceramic shell contain the same metal element. The sol precursor is added into the water in several times, and heated at a certain temperature and refluxed with water vapor to obtain a suspension-like liquid containing a hydrolyzed precipitate at the bottom of the suspension-like liquid. Optionally, the ceramic material of the ceramic shell is aluminum oxide ceramic, and aluminum isopropoxide is a hydrolysis precursor.

[0039] In step 202, a strong acid is added into the suspension-like liquid in several times, and clarified sol is obtained in the heating reflux manner.

[0040] In an example, the strong acid is added into the above liquid in several times and continuously heated and refluxed until the solution becomes the uniformly clarified sol.

[0041] In step 203, the sol prepared in advance is coated on the inner surface of the ceramic shell by using any of the following coating methods or a combination of thereof: dip-coating, casting, spin-coating and spraying.

[0042] In step 204, the ceramic shell coated with the sol is sintered by using the sintering process and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell.

[0043] In an example, the ceramic shell coated with the sol is kept in a dust-free environment for a period of time to obtain the ceramic shell including the transition layer having nano-sized micro-pores on the surface.

[0044] In step 205, the ceramic shell is connected with the plastic part through the transition layer by bonding or injection molding to prepare the target shell.

[0045] According to the technical solution provided by the embodiments of the present disclosure, the sol is coated on the surface of the ceramic shell and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell by using a low-temperature sintering process. Therefore, mechanical anchor points are provided for combination of the ceramics and the plastic part, the mechanical lock effect is formed, the bonding between the ceramics and the plastic parts is improved. In addition, the process of connecting the ceramics and the plastic parts does not require special surface treatment on the ceramic surfaces, thereby reducing the processing procedure of the ceramic shell, reducing the production energy consumption and being simple to operate. The technical solution may be applied to conventional engineering plastics or rubbers. The design space of ceramic and plastic material selection is greatly expanded; the transition layer does not affect the polish or glaze decoration of the outer surface of the ceramic shell.

[0046] FIG. 3 is a diagrammatic cross section showing a shell illustrated according to an exemplary embodiment. The shell in FIG. 3 is produced by using the steps of the processing method of the shell provided by any of the method embodiments of the present disclosure. As shown in FIG. 3, the shell includes:
a ceramic shell 31 and a plastic part 32; herein, an inner surface of the ceramic shell 31 is provided with a transition layer 33 having nano-sized micro-pores 331; the ceramic shell 31 is connected with the plastic part 32 through the transition layer 33.

[0047] In an example, the transition layer 33 includes a mesoporous structure or a microporous structure.

[0048] In an example, the ceramic shell 31 is connected with the plastic part 32 through the transition layer 33 by bonding or injection molding.

[0049] According to the technical solution provided by the embodiments of the present disclosure, the sol is coated on the surface of the ceramic shell and the transition layer having nano-sized micro-pores is formed on the inner surface of the ceramic shell by using a low-temperature sintering process. Therefore, mechanical anchor points are provided for combination of the ceramics and the plastic part, the mechanical lock effect is formed, the bonding between the ceramics and the plastic parts is improved. In addition, the process of connecting the ceramics and the plastic parts does not require special surface treatment on the ceramic surfaces, thereby reducing the processing procedure of the ceramic shell, reducing the production energy consumption and being simple to operate.

[0050] Other implementation solutions of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the present disclosure. This application is intended to cover any variations, uses, or adaptations of the present disclosure following the general principles thereof and including such departures from the present disclosure as come within known or customary practice in the art. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the present disclosure being indicated by the following claims.

[0051] It will be appreciated that the present disclosure is not limited to the exact construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof. It is intended that the scope of the present disclosure only be limited by the appended claims.


Claims

1. A processing method of a shell of a terminal, characterized in that the processing method comprises:

coating a sol prepared in advance on an inner surface of a ceramic shell prepared in advance (101);

sintering the ceramic shell coated with the sol by using a sintering process, forming a transition layer having nano-sized micro-pores on the inner surface of the ceramic shell (102, 204), and

connecting the ceramic shell and a plastic part through the transition layer to prepare a target shell (103).


 
2. The method of claim 1, wherein a component of the sol comprises any of the following elements or a combination thereof: Al, Zr or Zn.
 
3. The method of claim 1 or 2, wherein a component of the ceramic shell comprises any of the following materials or a combination thereof: aluminum oxide, zirconium oxide or zinc oxide.
 
4. The method of any one of claims 1 to 3, wherein before coating the sol prepared in advance on the inner surface of the ceramic shell, the method further comprises:

adding a sol precursor into water in several times, and obtaining a suspension-like liquid in a heating reflux manner, the suspension-like liquid containing a hydrolyzed precipitate at a bottom of the suspension-like liquid (201);

adding a strong acid into the suspension-like liquid in several times, and obtaining clarified sol in the heating reflux manner (202).


 
5. The method of any one of claims 1 to 4, wherein coating the sol prepared in advance on the inner surface of the ceramic shell comprises:
coating the sol prepared in advance on the inner surface of the ceramic shell by using any of the following coating methods or a combination thereof: dip-coating, casting, spin-coating and spraying (203).
 
6. The method of any one of claims 1 to 5, wherein sintering the ceramic shell coated with the sol by using the sintering process comprises:

keeping the ceramic shell coated with the sol in a dust-free environment for a preset time, and then placing the ceramic shell in a sintering furnace for sintering treatment;

wherein a sintering temperature ranges from 660 degrees centigrade to 850 degrees centigrade, and a heat preservation time is at least 1 hour.


 
7. The method of any one of claims 1 to 6, wherein connecting the ceramic shell and the plastic part through the transition layer to prepare the target shell comprises:
connecting the ceramic shell and the plastic part through the transition layer by bonding or injection molding to prepare the target shell (205).
 
8. A shell, characterized in that the shell is produced by using the steps of the method of any of claims 1-7, the shell comprises:

a ceramic shell (31) and a plastic part (32), wherein a transition layer (33) having nano-sized micro-pores (331) is formed on an inner surface of the ceramic shell (31);

the ceramic shell (31) is connected with the plastic part (32) through the transition layer (33).


 
9. The shell of claim 8, wherein the ceramic shell (31) is connected with the plastic part (32) through the transition layer (33) by bonding or injection molding.
 




Drawing




















REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description