Housing and manufacturing method therefor, and foldable terminal

Abstract

Provided in the present application are a housing and a manufacturing method therefor, and a foldable terminal. The foldable terminal comprises a hinge and a housing, the housing being rotatably connected to the hinge. The housing comprises a housing body and an anti-friction coating, the anti-friction coating being formed on the surface of the housing body. The housing body comprises a first surface and a second surface, wherein the first surface comprises a first sub-surface and a second sub-surface, and the orientations of the first sub-surface and the second sub-surface are the same. The anti-friction coating comprises a bonding resin and an anti-friction material, wherein the bonding resin includes a polyurethane acrylic resin; and the anti-friction material includes graphite or / and molybdenum disulfide. When the foldable terminal is in an unfolded state, the first sub-surface is arranged opposite the outer surface of the hinge. When the housing is opposite the hinge, the first sub-surface slides along the outer surface of the hinge. In the foldable terminal provided in the present application, by providing the anti-friction coating on the housing and adding the anti-friction material to the anti-friction coating, the friction force between the housing and the outer surface of the hinge can be reduced.

Description

Housing and its manufacturing method, foldable terminal

[0001] This application claims priority to Chinese Patent Application No. 202510494352.5, filed on April 18, 2025, entitled “Housing and Manufacturing Method Thereof, Foldable Terminal”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electronic product technology, and in particular to a housing and its manufacturing method, and a foldable terminal. Background Technology

[0003] With the development of technology, the appearance of electronic devices (such as mobile phones and tablets) is trending from candybar phones to foldable phones. Foldable phones, when open, feature a large display screen, fully satisfying consumers' visual experience, while their compact size when closed makes them easy to carry. Foldable phones generally unfold or close via a hinge. During the production, assembly, or use of foldable phones, the flatness of the middle frame is prone to change, causing friction between the middle frame and the hinge cover during unfolding or closing. In existing technologies, the friction loss between the middle frame and the hinge cover is relatively large, affecting the appearance of the hinge cover and impacting the user experience. Summary of the Invention

[0004] This application provides a housing and its manufacturing method, as well as a foldable terminal, which can solve the technical problem that the frictional loss between the housing and the shaft cover is large, which will affect the appearance of the shaft cover.

[0005] In a first aspect, this application provides a housing. Applied to a foldable terminal, the foldable terminal includes a pivot shaft rotatably connected to the housing. The housing includes a housing body and a friction-reducing coating. The housing body includes a first surface and a second surface, the first surface and the second surface being disposed opposite to each other along the thickness direction of the housing body. The first surface includes a first sub-surface and a second sub-surface, the first sub-surface and the second sub-surface having the same orientation. The friction-reducing coating includes a resin and a friction-reducing material. The resin includes a polyurethane acrylic resin, and the friction-reducing material includes graphite and / or molybdenum disulfide. The friction-reducing coating is formed on the first sub-surface. When the foldable terminal is in an unfolded state, the first sub-surface is positioned opposite to the outer surface of the pivot shaft.

[0006] In this embodiment, by forming a friction-reducing coating on the first sub-surface of the housing body and adding friction-reducing materials to the friction-reducing coating, the surface friction coefficient of the friction-reducing coating can be reduced. When the housing is applied to a foldable terminal, the friction between the housing and the shaft cover can be reduced, thereby reducing the wear of the housing on the outer surface of the shaft. This can reduce or even avoid the impact on the appearance of the shaft and improve the user experience.

[0007] Meanwhile, in this embodiment, polyurethane acrylic resin is used as the bonding resin for the friction-reducing coating, which gives the friction-reducing coating good flexibility and hardness. At the same time, the friction-reducing coating can be cured by ultraviolet light irradiation, which can reduce the curing temperature of the friction-reducing coating, that is, reduce the manufacturing temperature of the shell, thereby reducing the impact on the flatness of the shell and improving the production yield of the shell and the foldable terminal.

[0008] In one possible implementation, the resin in the friction-reducing coating is 30 to 55 parts by weight, and the friction-reducing material in the friction-reducing coating is 30 to 65 parts by weight.

[0009] In one possible implementation, the friction-reducing material comprises graphite, which includes flake-layered graphite and / or fluorinated graphite.

[0010] Fluorinated graphite is a compound formed by covalent bonds between fluorine atoms and carbon atoms that constitute the network plane. Fluorinated graphite itself has a very low coefficient of friction and floats on the surface of the anti-friction coating. In this embodiment, by adding fluorinated graphite to the anti-friction coating, the surface energy of the anti-friction coating can be further reduced, thereby further reducing the surface friction coefficient of the anti-friction coating. When the housing is applied to a foldable terminal, by adding fluorinated graphite to the anti-friction coating, the friction between the housing and the outer surface of the foldable terminal's pivot can be further reduced, thereby further reducing the wear of the housing on the outer surface of the foldable terminal's pivot.

[0011] In one possible implementation, the friction-reducing coating further includes a wear-resistant material, which includes one or more of nano-oxides and metal carbides.

[0012] It is understood that wear-resistant materials such as nano-alumina possess high hardness and good wear resistance. In this embodiment, by adding wear-resistant materials to the friction-reducing coating, the hardness and wear resistance of the coating can be improved, thereby reducing wear on the coating. Simultaneously, in this embodiment, adding wear-resistant materials to the friction-reducing coating can also enhance the adhesion between the coating and the substrate; that is, by strengthening the adhesion of the coating, it allows the coating to adhere more firmly to the surface of the housing, reducing the risk of the coating detaching.

[0013] In one possible implementation, the wear-resistant material comprises nano-alumina.

[0014] In one possible implementation, the thickness of the friction-reducing coating is 30μm to 50μm to ensure the wear resistance and adhesion of the friction-reducing coating.

[0015] In one possible implementation, the pencil hardness of the friction-reducing coating is 5B to 2B, so that the friction-reducing coating has good wear resistance and reduces or even avoids wear on the friction-reducing coating.

[0016] In one possible implementation, the surface friction coefficient of the anti-friction coating is less than 0.1, so that the anti-friction coating has a low surface friction coefficient, thereby reducing the friction between the outer surface of the housing and the shaft, and further reducing the wear of the housing on the outer surface of the shaft of the foldable terminal.

[0017] In one possible implementation, the housing body is provided with a receiving groove. The receiving groove includes a third sub-surface and a first sub-surface, the third sub-surface being connected between the first sub-surface and the second sub-surface. The anti-friction coating is elongated and is disposed on the first sub-surface along the length direction of the housing.

[0018] In one possible implementation, the housing body includes a receiving groove. The receiving groove includes a third sub-surface and a first sub-surface, the third sub-surface being connected between the first sub-surface and the second sub-surface. The anti-friction coating includes a plurality of first sub-coatings, the plurality of first sub-coatings being spaced apart along the length direction of the housing on the first sub-surface.

[0019] Secondly, this application provides a method for manufacturing a shell. The method includes:

[0020] Provide the housing body;

[0021] A friction-reducing coating is provided, the friction-reducing coating comprising a bonding resin and a friction-reducing material, the bonding resin comprising a polyurethane acrylic resin, and the friction-reducing material comprising graphite and / or molybdenum disulfide;

[0022] The anti-friction coating is sprayed onto the surface of the housing body to obtain a first intermediate housing.

[0023] The first intermediate shell is placed under ultraviolet light to irradiate it, so that the friction-reducing coating is cured to form a friction-reducing coating, thereby obtaining the shell.

[0024] In this embodiment, by forming an anti-friction coating on the surface of the housing body, the surface friction coefficient of the housing can be reduced, thereby improving the wear resistance of the housing. Furthermore, the housing manufacturing method provided in this embodiment allows the anti-friction coating to be formed on the surface of the housing body through spraying, resulting in a simple manufacturing process and low manufacturing cost.

[0025] Meanwhile, the shell manufacturing method provided in this embodiment uses polyurethane acrylic resin as the bonding resin, which allows the anti-friction coating to be cured by ultraviolet light irradiation. This reduces the curing temperature of the anti-friction coating, which in turn reduces the maximum temperature required to manufacture the shell. This reduces the risk of heat deformation of the shell and can reduce or even avoid the impact of excessive temperature on the flatness of the shell, thereby improving the production yield of the shell. It also prevents the shell from deforming and causing wear between it and the bushing, which further reduces wear between the shell and the bushing. At the same time, it can also prevent the deformation of the shell from affecting the size and shape of the holes and structural components in the shell, thereby improving the assembly accuracy of the foldable terminal.

[0026] Furthermore, the housing manufacturing method provided in this embodiment uses polyurethane acrylic resin as the bonding resin, which can improve the flexibility and hardness of the friction-reducing coating, thereby further improving the wear resistance of the friction-reducing coating and further reducing the friction between the friction-reducing coating and the bushing.

[0027] In one possible implementation, prior to the step of "spraying the anti-friction coating onto the surface of the housing body," the manufacturing method further includes:

[0028] Provide primer solvent;

[0029] The shell body is immersed in the primer solvent so that the primer solvent adheres to the surface of the shell body and forms a primer layer on the surface of the shell body to obtain a second intermediate shell.

[0030] In the step of “spraying the anti-friction coating onto the surface of the housing body”, the anti-friction coating is sprayed onto the surface of the primer layer.

[0031] In this embodiment, by first forming a primer layer on the surface of the housing body and then forming a friction-reducing coating, the adhesion between the friction-reducing coating and the housing body can be improved, thereby extending the service life of the friction-reducing coating, and further extending the service life of the housing and the foldable terminal.

[0032] In one possible implementation, the primer layer comprises one or more of carbonate activators, zirconate activators, phosphate activators, and silane coupling agents.

[0033] In one possible implementation, before the step of "immersing the shell body in the primer solvent", the manufacturing method further includes: cleaning the shell body sequentially with a cleaning agent and water, and then drying the shell body with high-pressure oil-free gas.

[0034] In this embodiment, before the step of "immersing the housing body in the primer solvent," the housing body is cleaned with a cleaning agent to remove stains and dust from its surface. This allows the anti-friction coating to adhere better to the surface of the housing body, thus improving the adhesion of the anti-friction coating and extending its service life. Furthermore, by cleaning the housing body to remove stains and dust, this embodiment avoids defects such as pores that could occur during the formation of the anti-friction coating, thereby improving the density, smoothness, and uniformity of the formed anti-friction coating.

[0035] Furthermore, in this embodiment, after cleaning the housing body with a cleaning agent, it is then cleaned with water to remove any remaining cleaning agent from the surface of the housing body. Simultaneously, after cleaning the housing body with water, it is dried with high-pressure oil-free gas to remove any residual water from the surface of the housing body.

[0036] In one possible implementation, before the step of "spraying the anti-friction coating onto the surface of the housing body", the manufacturing method further includes: mixing the anti-friction coating with a diluent to obtain a diluted anti-friction coating.

[0037] "Spraying the anti-friction coating onto the surface of the housing body to obtain a first intermediate housing" includes spraying the diluted anti-friction coating onto the surface of the housing body to obtain the first intermediate housing.

[0038] In this embodiment, by diluting the anti-friction coating before spraying it onto the surface of the housing body, the uniformity of the anti-friction coating spraying can be improved, thereby improving the uniformity of the formed anti-friction coating.

[0039] In one possible implementation, the friction-reducing coating further includes a photoinitiator, which includes one or more of benzoin derivatives, α-hydroxy ketone photoinitiators, and acylphosphine oxide photoinitiators.

[0040] In this embodiment, by adding a photoinitiator to the friction-reducing coating, the cross-linking of resins such as polyurethane acrylic resin can be promoted, thereby increasing the curing rate of the resin and thus improving the production efficiency of the friction-reducing coating, that is, improving the production efficiency of the shell.

[0041] In one possible implementation, the friction-reducing coating further includes a crosslinking agent comprising a thiol monomer having a functionality of 3 to 5.

[0042] In this embodiment, by adding a crosslinking agent such as a thiol monomer to the friction-reducing coating, the crosslinking of polyurethane acrylic acid can be promoted, forming a dense crosslinked network, thereby improving the hardness and wear resistance of the friction-reducing coating. Furthermore, in this embodiment, using a thiol monomer with a functionality of 3-5 as the crosslinking agent can further improve the degree of crosslinking of the bonding resin and further enhance the density of the polyurethane acrylic acid crosslinked network, thus giving the bonding resin better mechanical properties, and further improving the hardness and wear resistance of the friction-reducing coating.

[0043] In one possible embodiment, the friction-reducing coating further includes a film-forming aid, which includes one or more of benzyl alcohol, ethylene glycol, propylene glycol, hexanediol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, and dipropylene glycol monomethyl ether.

[0044] In this embodiment, by adding a film-forming aid to the friction-reducing coating, the film formation of the friction-reducing coating can be promoted, that is, the friction-reducing coating can be cured to form a friction-reducing coating, thereby improving the manufacturing efficiency of the friction-reducing coating and the shell, and reducing the film-forming temperature of the friction-reducing coating, that is, reducing the manufacturing temperature of the shell.

[0045] In one possible implementation, the friction-reducing coating comprises:

[0046] 30-55 parts by weight of polyurethane acrylic resin;

[0047] 10-20 parts by weight of flake-layered graphite;

[0048] 2 to 5 parts by weight of fluorinated graphite;

[0049] 25-40 parts by weight of molybdenum disulfide;

[0050] 2-5 parts by weight of photoinitiator;

[0051] 1 to 3 parts by weight of thiol monomer;

[0052] 3 to 9 parts by weight of nano-alumina particles;

[0053] 5 to 10 parts by weight of film-forming aid.

[0054] Thirdly, this application provides a foldable terminal, including a hinge and a housing. The housing is rotatably connected to the hinge. When the foldable terminal is in an unfolded state, a first sub-surface is disposed opposite to the outer surface of the hinge. And when the housing is relative to the hinge, the first sub-surface slides along the outer surface of the hinge.

[0055] The foldable terminal provided in this embodiment can reduce the friction between the housing and the outer surface of the pivot by setting a friction-reducing coating on the housing. This can reduce or even avoid wear on the coating on the outer surface of the pivot, thereby improving the aesthetics of the foldable terminal and enhancing the user experience.

[0056] In one possible implementation, the shaft includes a shaft cover, a bracket, and an anti-fingerprint coating. The shaft cover is fixedly connected to the bracket, and the anti-fingerprint coating is formed on the surface of the shaft cover facing away from the bracket; and when the housing is relative to the shaft, the anti-friction coating slides along the anti-fingerprint coating.

[0057] The anti-fingerprint coating has hydrophobic and oleophobic properties, which can reduce or eliminate the adhesion of fingerprints, oil stains, and dirt to the outer surface of the shaft cover. In this embodiment, by applying an anti-fingerprint coating to the outer surface of the shaft cover, the aesthetics of the foldable terminal can be improved, and cleaning can be simplified and the cleaning frequency reduced.

[0058] The foldable terminal provided in this embodiment reduces the coefficient of friction between the anti-friction coating and the anti-fingerprint coating by setting an anti-friction coating on the housing. In other words, it reduces the coefficient of friction between the hinge cover and the housing, thereby reducing or even avoiding wear on the anti-fingerprint coating and thus reducing or even avoiding the impact on the appearance of the hinge cover, improving the user experience.

[0059] In one possible implementation, the difference between the pencil hardness of the anti-friction coating and the pencil hardness of the anti-fingerprint coating is less than or equal to a pencil hardness range, so as to further improve the wear resistance of the anti-friction coating and the anti-fingerprint coating, and further reduce the wear on the anti-fingerprint coating.

[0060] In summary, the foldable terminal provided in this application reduces the surface friction coefficient of the anti-friction coating by setting an anti-friction coating on the housing and adding anti-friction materials to the anti-friction coating. This reduces the friction between the housing and the hinge cover of the foldable terminal, thereby reducing the wear of the housing on the hinge cover and thus reducing or even avoiding the impact on the appearance of the hinge cover, improving the user experience.

[0061] Meanwhile, in this application, polyurethane acrylic resin is used as the bonding resin for the friction-reducing coating, which gives the friction-reducing coating good flexibility and hardness. At the same time, the friction-reducing coating can be cured by ultraviolet light irradiation, which can reduce the curing temperature of the friction-reducing coating, thereby reducing the manufacturing temperature of the shell, thus reducing the impact on the flatness of the shell and improving the production yield of foldable terminals. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of this application or the background art, the accompanying drawings used in the embodiments of this application or the background art will be described below.

[0063] Figure 1 is a structural schematic diagram of the foldable terminal provided in the embodiment of this application in the folded state;

[0064] Figure 2 is a structural schematic diagram of the foldable terminal shown in Figure 1 in its unfolded state;

[0065] Figure 3 is an exploded view of the foldable terminal shown in Figure 2;

[0066] Figure 4 is a partially exploded structural diagram of the foldable terminal shown in Figure 2 from another angle.

[0067] Figure 5 is a partial cross-sectional view of the foldable terminal shown in Figure 2 along the AA direction.

[0068] Figure 6 is a schematic diagram of the foldable terminal shown in Figure 5 in a folded state.

[0069] Figure 7 is a partially exploded structural diagram of a foldable terminal provided in another embodiment of this application;

[0070] Figure 8 is a surface morphology diagram of the anti-friction coating in the shell shown in Figure 4;

[0071] Figure 9 is a flowchart of the manufacturing process of the shell provided in this application;

[0072] Figure 10 is a schematic diagram of the structure of the shell body provided by the manufacturing method shown in Figure 9;

[0073] Figure 11 is a schematic diagram of the structure of the second intermediate shell obtained in step S2 of the manufacturing method shown in Figure 9;

[0074] Figure 12 is a schematic diagram of the shell structure obtained by the manufacturing method shown in Figure 9. Detailed Implementation

[0075] The embodiments of this application are described below with reference to the accompanying drawings.

[0076] Please refer to Figures 1 and 2. Figure 1 is a structural schematic diagram of the foldable terminal 100 provided in the embodiment of this application in the folded state, and Figure 2 is a structural schematic diagram of the foldable terminal 100 shown in Figure 1 in the unfolded state.

[0077] For ease of description, the width direction of the foldable terminal 100 is defined as the X direction, the length direction as the Y direction, and the thickness direction as the Z direction. The X, Y, and Z directions are mutually perpendicular. It should be understood that the directional terms such as "top" and "bottom" used in the description of the embodiments of this application are mainly based on the orientation of the foldable terminal 100 shown in Figure 2, with the positive Z-axis direction being "top" and the negative Z-axis direction being "bottom," and do not constitute a limitation on the orientation of the foldable terminal 100 in actual application scenarios.

[0078] The foldable terminal 100 includes, but is not limited to, mobile phones, laptops, tablets, personal digital assistants, wearable devices, or in-vehicle devices. In this embodiment, an inward-folding mobile phone is used as an example for illustration.

[0079] The foldable terminal 100 shown in this embodiment is an electronic device capable of being folded once. In some other embodiments, the foldable terminal 100 may also be an electronic device capable of being folded multiple times (more than twice). In this case, the foldable terminal 100 may include multiple parts, with adjacent parts folded relatively close together until the foldable terminal 100 is in a folded state, and adjacent parts unfolded relatively far apart until the foldable terminal 100 is in an unfolded state.

[0080] Please refer to Figure 3, which is an exploded structural diagram of the foldable terminal 100 shown in Figure 2.

[0081] The foldable terminal 100 includes a housing 10, a hinge 20, and a display screen 30. The housing 10 has a receiving slot for accommodating the hinge 20. In this embodiment, the foldable terminal 100 includes two housings 10. The two housings 10 are a first housing 10a and a second housing 10b. The first housing 10a has a first receiving slot 13a, and the second housing 10b has a second receiving slot 13b.

[0082] The rotating shaft 20 includes a base 201, a first rotating assembly, and a second rotating assembly. The first and second rotating assemblies are respectively mounted on opposite sides of the base 201 in the X direction and are rotatably connected to the base 201. It should be noted that the first and second rotating assemblies of the rotating shaft 20 are not shown in Figure 3. The first rotating assembly may include a swing arm, a wedge block, and a door panel, etc. The second rotating assembly may also include a swing arm, a wedge block, and a door panel, etc. The swing arm can be any one or more of a main swing arm, a secondary swing arm, a synchronous swing arm, and a damping swing arm.

[0083] A rotating shaft 20 is located between the first housing 10a and the second housing 10b, and within a receiving groove. A first rotating assembly is connected to the first housing 10a, and a second rotating assembly is connected to the second housing 10b. When the first housing 10a rotates, it causes the first rotating assembly to rotate relative to the base 201. When the second housing 10b rotates, it causes the second rotating assembly to rotate relative to the base 201, thereby allowing the foldable terminal 100 to switch between a folded state and an unfolded state.

[0084] The display screen 30 includes a first display portion 31, a second display portion 32, and a flexible portion 33. The flexible portion 33 is connected between the first display portion 31 and the second display portion 32, and is capable of bending along the Y direction. The display screen 30 is mounted on a first housing 10a, a second housing 10b, and a pivot 20. The first display portion 31 is mounted on the first housing 10a, the second display portion 32 is mounted on the second housing 10b, and the pivot 20 is positioned opposite to the flexible portion 33. The first housing 10a and the second housing 10b can rotate relative to each other via the pivot 20, thereby causing the first display portion 31 and the second display portion 32 to rotate relative to each other, and causing the flexible portion 33 to bend, allowing the foldable terminal 100 to switch between a folded state and an unfolded state.

[0085] When the first housing 10a and the second housing 10b rotate toward each other via the pivot 20, the display screen 30 bends, causing the foldable terminal 100 to be in a folded state. When the foldable terminal 100 is in the folded state, the bendable portion 33 of the display screen 30 bends, and the first display portion 31 and the second display portion 32 are positioned opposite each other. At this time, the display screen 30 is positioned between the first housing 10a and the second housing 10b, which greatly reduces the probability of damage to the display screen 30 and effectively protects it.

[0086] When the first housing 10a and the second housing 10b rotate in opposite directions via the pivot 20, they cause the display screen 30 to unfold, thus placing the foldable terminal 100 in the unfolded state. When the foldable terminal 100 is in the unfolded state, the bendable portion 33 unfolds, and the first display portion 31 and the second display portion 32 unfold relative to each other. At this time, the display surface of the display screen 30 is approximately flat, providing a large display area, thereby achieving a large-screen display for the foldable terminal 100 and improving the user experience.

[0087] Please refer to Figures 3 and 4. Figure 4 is a partially exploded structural diagram of the foldable terminal 100 shown in Figure 2 from another angle.

[0088] The housing 10 includes a housing body 12. The housing body 12 includes a first surface 121 and a second surface 122, which are disposed opposite to each other along the thickness direction of the housing body 12. The first surface 121 includes a first sub-surface 1211 and a second sub-surface 1212, which have the same orientation. The housing body 12 also has a receiving groove 13. The receiving groove 13 is disposed on the first surface 121. The receiving groove 13 includes a third sub-surface 1213 and a first sub-surface 1211, which is connected between the first sub-surface 1211 and the second sub-surface 1212. It can be understood that the first sub-surface 1211 is the bottom wall surface of the receiving groove 13, and the third sub-surface 1213 is the side wall surface of the receiving groove 13. The first sub-surface 1211, the second sub-surface 1212, and the third sub-surface 1213 together form the first surface 121.

[0089] Specifically, the first housing 10a includes a first housing body 12a. The first housing body 12a includes a first surface 121a, a second surface 122a, a first side surface 123a, and a second side surface 124a. The first surface 121a and the second surface 122a are arranged opposite to each other along the thickness direction of the first housing 10a, that is, opposite to each other along the Z direction. The first side surface 123a and the second side surface 124a are arranged opposite to each other along the width direction of the first housing 10a, that is, opposite to each other along the X direction. Furthermore, the first side surface 123a and the second side surface 124a are both connected between the first surface 121a and the second surface 122a.

[0090] The first receiving groove 13a is disposed in the edge region of the first housing 10a near the first side surface 123a. In this embodiment, the first receiving groove 13a is elongated, and its length direction is parallel to the length direction of the first housing 10a, that is, parallel to the Y direction. The first receiving groove 13a includes a first sub-surface 1211a and a third sub-surface 1213a. The first sub-surface 1211a is parallel or substantially parallel to the XY plane. The third sub-surface 1213a is connected to the first sub-surface 1211a on one side in the X direction, and the third sub-surface 1213a is connected to the first sub-surface 1211a at an angle. In this embodiment, the third sub-surface 1213a is planar, and the third sub-surface 1213a is perpendicularly connected to the first sub-surface 1211a. In other embodiments, the third sub-surface 1213a may also be curved. Alternatively, the angle between the third sub-surface 1213a and the first sub-surface 1211a may be slightly greater than 90 degrees or slightly less than 90 degrees.

[0091] The first surface 121a also includes a second sub-surface 1212a, which is connected to the side of the third sub-surface 1213a facing away from the first sub-surface 1211a, and the orientation of the second sub-surface 1212a is the same as that of the first sub-surface 1211a. It can be understood that the first sub-surface 1211a is the bottom wall surface of the first receiving groove 13a, and the third sub-surface 1213a is the side wall surface of the first receiving groove 13a. The first sub-surface 1211a, the second sub-surface 1212a, and the third sub-surface 1213a together form the first surface.

[0092] Among them, the second surface 122a, the first side surface 123a, the second side surface 124a, the first sub-surface 1211a, the second sub-surface 1212a and the third sub-surface 1213a can all be referred to as the surfaces of the first housing body 12a.

[0093] The second housing 10b includes a second housing body 12b. In this embodiment, the second housing body 12b and the first housing body 12a are mirror images of each other. The second housing body 12b includes a first surface 121b, a second surface 122b, a first side surface 123b, and a second side surface 124b. The first surface 121b and the second surface 122b are disposed opposite to each other along the thickness direction of the second housing 10b. The first side surface 123b and the second side surface 124b are disposed opposite to each other along the width direction of the second housing 10b and are connected between the first surface 121b and the second surface 122b.

[0094] The second receiving groove 13b is located in the edge region of the second housing 10b near the first side surface 123b. In this embodiment, the second receiving groove 13b is elongated, and its length direction is parallel to the length direction of the second housing 10b, i.e., parallel to the Y direction. The second receiving groove 13b includes a first sub-surface 1211b and a third sub-surface 1213b. The first sub-surface 1211b is parallel or substantially parallel to the XY plane. The third sub-surface 1213b is connected to the first sub-surface 1211b on one side in the X direction, and the third sub-surface 1213b is connected to the first sub-surface 1211b at an angle. In this embodiment, the third sub-surface 1213b is planar, and it is perpendicularly connected to the first sub-surface 1211b. In other embodiments, the third sub-surface 1213b may also be curved. Alternatively, the angle between the third sub-surface 1213b and the first sub-surface 1211b may be slightly greater than 90 degrees or slightly less than 90 degrees.

[0095] The first surface 121b also includes a second sub-surface 1212b, which is connected to the side of the third sub-surface 1213b facing away from the first sub-surface 1211b, and the orientation of the second sub-surface 1212b is the same as that of the first sub-surface 1211b. It can be understood that the first sub-surface 1211b is the bottom wall surface of the second receiving groove 13b, and the third sub-surface 1213b is the side wall surface of the second receiving groove 13b. The first sub-surface 1211b, the second sub-surface 1212b, and the third sub-surface 1213b together form the first surface 121b.

[0096] Among them, the second surface 122b, the first side surface 123b, the second side surface 124b, the first sub-surface 1211b, the second sub-surface 1212b, and the third sub-surface 1213b can all be referred to as the surfaces of the second shell body 12b.

[0097] In this embodiment, the base 201 of the rotating shaft 20 includes a shaft cover 21 and a bracket 22. The shaft cover 21 includes a shaft cover body 211 and an anti-fingerprint coating 212. The shaft cover body 211 includes an inner surface 214 and an outer surface 213. The inner surface 214 and the outer surface 213 are arranged opposite to each other along the thickness direction of the shaft cover body 211. The bracket 22 is disposed inside the shaft cover body 211 and is fixedly connected to the shaft cover body 211. The bracket 22 is used to install structures such as the swing arm, synchronization component, and damping component of the rotating shaft 20.

[0098] An anti-fingerprint coating 212 is formed on the outer surface 213 of the shaft cover body 211. Specifically, the anti-fingerprint coating 212 can be formed on the outer surface 213 by processes such as spraying or brushing. The anti-fingerprint coating 212 has hydrophobic and oleophobic properties, which can reduce or eliminate the adhesion of fingerprints, oil stains, and dirt on the outer surface 213 of the shaft cover 21. In this embodiment, by providing an anti-fingerprint coating 212 on the outer surface 213 of the shaft cover 21, the aesthetics of the foldable terminal 100 can be improved, and the cleaning work can be simplified and the cleaning frequency reduced.

[0099] Please refer to Figures 5 and 6. Figure 6 is a structural schematic diagram of the foldable terminal 100 shown in Figure 5 in a folded state.

[0100] When the foldable terminal 100 is in the unfolded state, the first housing 10a and the second housing 10b are arranged parallel to each other along the X direction, and the pivot 20 connects the first housing 10a and the second housing 10b. When the display screen 30 is in the unfolded state, the first housing 10a, the second housing 10b, and the pivot 20 together support the display screen 30. At the same time, the anti-fingerprint coating 212 is at least partially located in the first receiving groove 13a and the second receiving groove 13b, and is in contact with the inner walls of the first receiving groove 13a and the second receiving groove 13b.

[0101] When the foldable terminal 100 is in a folded state, the first housing 10a and the second housing 10b are stacked, the display screen 30 is located between the first housing 10a and the second housing 10b, and the bendable portion 33 is bent. At the same time, the outer surface 213 of the shaft cover body 211 faces the outside of the foldable terminal 100, and the anti-fingerprint coating 212 is exposed on the outside of the foldable terminal 100.

[0102] When the foldable terminal 100 switches between an unfolded state and a closed state, the first housing 10a rotates relative to the shaft cover 21, the first sub-surface 1211a rotates relative to the shaft cover 21 along the outer surface of the shaft cover 21, and the first sub-surface 1211a and the outer surface of the shaft cover 21 slide relative to each other; at the same time, the second housing 10b rotates relative to the shaft cover 21, the first sub-surface 1211b rotates along the outer surface of the shaft cover 21, and the first sub-surface 1211b and the outer surface of the shaft cover 21 slide relative to each other.

[0103] It should be noted that during the production, assembly, or use of the foldable terminal 100, the flatness of the first housing 10a and the second housing 10b is prone to change, which can lead to unavoidable motion interference between the first housing 10a and the second housing 10b and the shaft cover 21 of the rotating shaft 20, resulting in frictional wear. In the prior art, when the foldable terminal 100 switches between the unfolded and closed states, both the first sub-surface 1211a and the first sub-surface 1211b come into contact with and rub against the anti-fingerprint coating 212 formed on the outer surface 213, causing wear on the anti-fingerprint coating 212, which in turn affects the appearance of the shaft cover 21 and the user experience.

[0104] Alternatively, in the prior art, the first sub-surfaces 1211a and 1211b are provided with polyoxymethylene wear blocks. When the first housing 10a rotates relative to the rotating shaft 20, the polyoxymethylene wear blocks come into contact with and rub against the anti-fingerprint coating 212 formed on the outer surface 213. Due to the high hardness of the polyoxymethylene wear blocks, long-term wear between the polyoxymethylene wear blocks and the anti-fingerprint coating 212 will cause wear to the anti-fingerprint coating 212, which will affect the appearance of the shaft cover 21 and the user experience.

[0105] As shown in Figure 4, the foldable terminal 100 provided in this application also includes a friction-reducing coating 11. In this embodiment, both the first housing 10a and the second housing 10b are formed with a friction-reducing coating 11. The first friction-reducing coating 11a is formed on the first housing 10a, and the second friction-reducing coating 11b is formed on the second housing 10b. Specifically, the first housing 10a includes a first housing body 12a and a first friction-reducing coating 11a. The first friction-reducing coating 11a is formed on the first housing body 12a. The second housing 10b includes a second housing body 12b and a second friction-reducing coating 11b. The second friction-reducing coating 11b is formed on the second housing body 12b. The first friction-reducing coating 11a can be formed on the surface of the first housing body 12a by spraying or the like, and the second friction-reducing coating 11b can be formed on the surface of the second housing body 12b by spraying or the like. In other embodiments, the friction-reducing coating 11 may be formed only on the first housing 10a, or the friction-reducing coating 11 may be formed only on the second housing 10b.

[0106] The following description uses the example of both the first housing 10a and the second housing 10b having a friction-reducing coating 11.

[0107] The first anti-friction coating 11a is formed on the first sub-surface 1211a. As shown in FIG4, in this embodiment, the first anti-friction coating 11a partially covers the first sub-surface 1211a. Specifically, the first anti-friction coating 11a is elongated and disposed along the Y direction, and the first anti-friction coating 11a is located in the edge region of the first sub-surface 1211a near the first side surface 123a.

[0108] The second anti-friction coating 11b is formed on the first sub-surface 1211b. As shown in FIG4, in this embodiment, the second anti-friction coating 11b partially covers the first sub-surface 1211b. Specifically, the second anti-friction coating 11b is elongated and disposed along the Y direction, and the second anti-friction coating 11b is located in the edge region of the first sub-surface 1211b near the first side surface 123b.

[0109] As shown in Figure 7, in one embodiment, the first anti-friction coating 11a may also include a plurality of first sub-coatings 111a. The plurality of first sub-coatings 111a are spaced apart along the Y direction on the first sub-surface 1211a. The shapes and sizes of the plurality of first sub-coatings 111a may be identical, partially identical, or completely different. For example, the first anti-friction coating 11a includes six first sub-coatings 111a, which are spaced apart along the Y direction on the first sub-surface 1211a. In other embodiments, the number of first sub-coatings 111a may be two, three, four, five, or six or more. No specific limitations are placed on the number, size, and shape of the first sub-coatings 111a here. The second anti-friction coating 11b may also include a plurality of second sub-coatings 111b. The plurality of second sub-coatings 111b are spaced apart along the Y direction on the first sub-surface 1211b. The shapes and sizes of the plurality of first sub-coatings 111a may be identical, partially identical, or completely different.

[0110] In one embodiment, the first anti-friction coating 11a may also completely cover the first sub-surface 1211a, and the second anti-friction coating 11b may also completely cover the first sub-surface 1211b.

[0111] Referring to Figures 5 and 6, when the foldable terminal 100 switches between the unfolded and closed states, the first housing 10a rotates relative to the shaft cover 21, and the first sub-surface 1211a rotates relative to the shaft cover 21 along the outer surface of the shaft cover 21. At this time, the first anti-friction coating 11a formed on the first sub-surface 1211a comes into contact with the anti-fingerprint coating 212 formed on the outer surface 213 and generates friction. That is, when the first sub-surface 1211a rotates relative to the shaft cover 21 along the outer surface of the shaft cover 21, the first anti-friction coating 11a and the anti-fingerprint coating 212 slide relative to each other.

[0112] Simultaneously, when the foldable terminal 100 switches between the unfolded and closed states, the second housing 10b rotates relative to the shaft cover 21, and the first sub-surface 1211b rotates along the outer surface of the shaft cover 21. At this time, the second anti-friction coating 11b formed on the first sub-surface 1211b comes into contact with the anti-fingerprint coating 212 formed on the outer surface 213 and generates friction. That is, when the first sub-surface 1211b rotates relative to the shaft cover 21 along the outer surface of the shaft cover 21, there is relative sliding between the surface of the second anti-friction coating 11b and the anti-fingerprint coating 212.

[0113] In this embodiment, by providing a first anti-friction coating 11a on the first housing 10a, the friction between the first housing 10a and the base 201 can be reduced, thereby reducing or even avoiding wear on the coating formed on the outer surface 213 of the shaft cover 21. For example, wear on the anti-fingerprint coating 212 can be reduced or even avoided, thereby improving the aesthetics of the foldable terminal 100 and enhancing the user's experience.

[0114] Furthermore, in this embodiment, by providing a second anti-friction coating 11b on the second housing 10b, the friction between the second housing 10b and the shaft cover 21 can be reduced, thereby further reducing or even avoiding wear on the coating formed on the outer surface 213 of the shaft cover 21. For example, it can further reduce or even avoid wear on the anti-fingerprint coating 212, thereby further improving the aesthetics of the foldable terminal 100 and further enhancing the user's experience.

[0115] The following section provides a detailed introduction to the friction-reducing coating 11.

[0116] The friction-reducing coating 11 includes resin, friction-reducing material, and wear-resistant material.

[0117] The resin in the anti-friction coating 11 comprises 30 to 55 parts by weight. The resin includes one or more of polyurethane resin, acrylic resin, polyurethane-acrylic resin, and silicone-modified polyurethane-acrylic resin.

[0118] In this embodiment, the resin is polyurethane acrylic resin. Polyurethane acrylic resin is a combination of polyurethane and acrylate, typically prepared by reacting isocyanate groups in a polyurethane prepolymer with hydroxyl acrylates. The molecular structure of polyurethane acrylic resin contains both urethane groups and double bonds of acrylate. In this embodiment, using polyurethane acrylic resin as the resin gives the friction-reducing coating 11 good flexibility and hardness. Simultaneously, the polyurethane acrylic resin can be cured by ultraviolet light, which can lower the curing temperature of the friction-reducing coating 11, thereby lowering the manufacturing temperature of the shell 10, further reducing the impact on the flatness of the shell 10, and improving the production yield of the shell 10 and the foldable terminal 100.

[0119] In one embodiment, the resin may be a silicone-modified polyurethane acrylate resin. The silicone includes one or more monomers selected from polyorganosiloxane, methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane. Exemplarily, the resin is a polyorganosiloxane-modified polyurethane acrylate resin, or the resin may be a mixture of polyorganosiloxane-modified polyurethane acrylate resin and methyltrichlorosilane-modified polyurethane acrylate resin. Using a silicone-modified polyurethane acrylate resin introduces silicone groups into the polyurethane acrylate resin, thereby improving the hardness and wear resistance of the friction-reducing coating 11, as well as its toughness, weather resistance, and yellowing resistance.

[0120] In one embodiment, the resin may also be a polyurethane resin or an acrylic resin to reduce the manufacturing cost of the anti-friction coating 11. Alternatively, the resin may be a mixture of polyurethane acrylic resin and silicone-modified polyurethane acrylic resin.

[0121] The friction-reducing material in the friction-reducing coating 11 comprises 30–65 parts by weight. The friction-reducing material is composed of layered materials. Layered materials refer to a class of materials formed by the stacking of multiple layers of atoms or molecules through interlayer interactions. Specifically, the layered material can be graphite or molybdenum disulfide, or a mixture of graphite and molybdenum disulfide. The graphite can be flake-layered graphite, fluorinated graphite, or a mixture of flake graphite and fluorinated graphite.

[0122] In this embodiment, the friction-reducing material includes flake-layered graphite, fluorinated graphite, and molybdenum disulfide (MoS2). Flake-layered graphite is a carbon material with a layered structure. Its crystal morphology exhibits a regular stacked appearance, with each layer of graphite consisting of a hexagonal lattice structure of carbon atoms. The carbon atoms between adjacent layers interact through van der Waals forces, forming a fish-scale-like stacking pattern. In this embodiment, the flake-layered graphite in the friction-reducing coating 11 comprises 10 to 20 parts by weight. The particle size of the flake-layered graphite is 1 μm to 3 μm. The interlayer spacing of the flake-layered graphite is less than 1 nm, that is, the distance between two adjacent graphite layers is less than 1 nm.

[0123] Molybdenum disulfide (MoD) is a two-dimensional layered transition metal chalcogenide. It has a hexagonal crystal structure, composed of molybdenum and sulfur atoms arranged in a specific pattern, with each molybdenum atom surrounded by six sulfur atoms, forming an octahedral structure. MoD can be viewed as a series of parallel Mo-S bilayers stacked together, with adjacent layers bonded together by van der Waals forces.

[0124] In this embodiment, the molybdenum disulfide is spherical particles. In this way, the sharpness of molybdenum disulfide can be reduced, so that the wear of the anti-fingerprint coating 212 on the shaft cover 21 caused by the molybdenum disulfide particles can be reduced, that is, the wear between the anti-friction coating 11 and the shaft cover 21 can be reduced, in other words, the wear of the shaft cover 21 by the housing 10 during the opening and closing process of the foldable terminal 100 can be reduced. The parts by weight of molybdenum disulfide in the anti-friction coating 11 is 25 to 40 parts by weight. The particle size of molybdenum disulfide is less than 1 μm. Preferably, the particle size of molybdenum disulfide is 400 nm to 800 nm, so as to avoid abrasion to the anti-fingerprint coating 212 caused by an excessively large particle size of molybdenum disulfide.

[0125] Fluorinated graphite is a compound formed by covalent bonding of fluorine atoms to carbon atoms constituting a network plane, and its chemical structural formula can be represented by (CFx)n, where x is an indefinite value, generally in the range of 0 < x < 1.25. In this embodiment, the parts by weight of fluorinated graphite in the anti-friction coating 11 is 2 to 5 parts by weight. The particle size of fluorinated graphite is 2 μm to 5 μm.

[0126] It should be noted that the scaly layered graphite, fluorinated graphite and molybdenum disulfide are microscopically composed of continuous layered materials, and the force between layers is relatively low. When the scaly layered graphite is subjected to external friction and wear, sliding occurs between two adjacent carbon atom layers in the scaly layered graphite, so that the friction interface is dispersed and transferred to the interlayer of the scaly layered graphite, which further makes adhesive friction difficult to proceed and reduces the wear probability of the anti-friction coating 11. Similarly, when the fluorinated graphite is subjected to external friction and wear, sliding occurs between two adjacent carbon atom layers in the fluorinated graphite, so that the friction interface is dispersed and transferred to the interlayer of the fluorinated graphite, which further makes adhesive friction difficult to proceed and reduces the wear probability of the anti-friction coating 11. When molybdenum disulfide is subjected to external friction and wear, sliding occurs between two adjacent Mo-S diatomic layers in molybdenum disulfide, so that the friction interface is dispersed and transferred to the interlayer of molybdenum disulfide, which further makes adhesive friction difficult to proceed and further reduces the wear probability of the anti-friction coating 11.

[0127] In this embodiment, by adding the anti-friction material composed of layered materials into the anti-friction coating 11, when the anti-friction coating 11 is subjected to friction, the friction interface is mainly concentrated between the layers of the layered material, and the force between the layers of the layered material is relatively low. In this way, the friction coefficient between the anti-friction coating 11 and the anti-fingerprint coating 212 can be reduced, that is, the friction coefficient between the shaft cover 21 and the housing 10 can be reduced, so that the abrasion to the anti-fingerprint coating 212 can be reduced or even avoided, and further the influence on the appearance of the shaft cover 21 can be reduced or even avoided, improving the user's use experience.

[0128] Meanwhile, due to the inherent sliding balance between the layers of materials such as flake-layered graphite, fluorinated graphite, and molybdenum disulfide, a continuous lubricating film exists on their surfaces, exhibiting a very low coefficient of friction. This further reduces the coefficient of friction between the anti-friction coating 11 and the anti-fingerprint coating 212, and consequently, between the shaft cover 21 and the housing 10. This further reduces or even eliminates wear on the anti-fingerprint coating 212, and minimizes or even eliminates any impact on the appearance of the shaft cover 21, thus improving the user experience.

[0129] Furthermore, fluorinated graphite itself has a very low coefficient of friction, and it floats on the surface of the anti-friction coating 11. In this embodiment, by adding fluorinated graphite to the anti-friction coating 11, the surface energy of the anti-friction coating 11 can be further reduced, thereby further reducing the surface friction coefficient of the anti-friction coating 11, further reducing the friction coefficient between the anti-friction coating 11 and the anti-fingerprint coating 212, and further reducing the friction coefficient between the shaft cover 21 and the housing 10. This further reduces or even avoids wear on the anti-fingerprint coating 212, and further reduces or even avoids the impact on the appearance of the shaft cover 21, improving the user experience.

[0130] In this embodiment, the wear-resistant material in the friction-reducing coating 11 is 3 to 9 parts by weight. It should be noted that the wear-resistant material referred to here is a material with high hardness that can improve the wear resistance of the friction-reducing coating 11. Specifically, the wear-resistant material can be a nano-oxide or a metal carbide, or a mixture of nano-oxide and metal carbide. The nano-oxide includes one or more of nano-silicon oxide and nano-alumina, and the metal carbide includes one or more of tungsten carbide and chromium carbide.

[0131] In this embodiment, the wear-resistant material is alumina. Specifically, the wear-resistant material is granular alumina. Preferably, the wear-resistant material is spherical granular alumina to reduce the sharpness of the alumina particles, thereby reducing the wear of the alumina particles on the anti-fingerprint coating 212 on the shaft cover 21, that is, reducing the wear between the anti-friction coating 11 and the shaft cover 21, which means reducing the wear of the housing 10 on the shaft cover 21 during the opening and closing of the foldable terminal 100. The particle size of the alumina is nanometer-scale. That is, the alumina used in this embodiment is nano-alumina. Preferably, the particle size of the nano-alumina is 300nm to 500nm.

[0132] It is understood that wear-resistant materials such as nano-alumina possess high hardness and good wear resistance. In this embodiment, by adding wear-resistant materials to the friction-reducing coating 11, the hardness and wear resistance of the friction-reducing coating 11 can be improved, thereby reducing the wear of the friction-reducing coating 11. Simultaneously, in this embodiment, adding wear-resistant materials to the friction-reducing coating 11 can also enhance the adhesion between the friction-reducing coating 11 and the substrate, that is, enhance the adhesion between the friction-reducing coating 11 and the shell body, making the friction-reducing coating 11 more firmly attached to the surface of the shell body, reducing the risk of the friction-reducing coating 11 detaching.

[0133] Please refer to Figure 8, which is a surface morphology diagram of the anti-friction coating 11 in the housing 10 shown in Figure 4.

[0134] As shown in the figure, in this embodiment, the surface morphology of the anti-friction coating 11 is smooth.

[0135] The anti-friction coating 11 provided in this embodiment has a thickness of 30μm to 50μm to ensure its wear resistance and adhesion. Furthermore, the anti-friction coating 11 has a low coefficient of surface friction. For example, the coefficient of surface friction of the anti-friction coating 11 is less than or equal to 0.1.

[0136] In this embodiment, the pencil hardness of the anti-friction coating 11 is 5B to 2B. Furthermore, the anti-friction coating 11 and the anti-fingerprint coating 212 have matching hardness. "Matching hardness" here means that the hardness is the same or similar. In this embodiment, the difference between the pencil hardness of the anti-friction coating 11 and the pencil hardness of the anti-fingerprint coating 212 is less than or equal to one pencil hardness range. For example, the pencil hardness corresponding to both the anti-friction coating 11 and the anti-fingerprint coating 212 is 2B. Alternatively, the pencil hardness corresponding to the anti-friction coating 11 is 2B, and the pencil hardness corresponding to the anti-fingerprint coating 212 is 3B. This further improves the wear resistance of the anti-friction coating 11 and the anti-fingerprint coating 212, and further reduces wear on the anti-fingerprint coating 212.

[0137] The pencil hardness of the anti-friction coating 11 and the anti-fingerprint coating 212 can be tested using the following method:

[0138] (i) Place the sharpened pencil into the instrument fixture and fix it on the sample stage.

[0139] (ii) Adjust the horizontal weights so that the surface load of the pencil on the test sample is zero, and then add a weight of 1 ± 0.05 kg.

[0140] (iii) Move the test sample 3 mm in the opposite direction to the pencil, at a speed of approximately 0.5 mm / s.

[0141] (iv) Rotate the pencil so that the undamaged lead edge contacts the coating, and change the test position, scratching 5 times in sequence. Start the test with the hardest pencil, and find the pencil that cannot scratch the coating of the surface of the test sample at least 4 out of 5 times. The hardness of this pencil is the pencil hardness of the coating of the surface of the test sample.

[0142] In step (ii), the test sample is a sample with a coating to be tested on its surface. When the surface of the test sample has a friction-reducing coating 11, the pencil hardness measured in step (iv) is the hardness of the friction-reducing coating 11. When the surface of the test sample has an anti-fingerprint coating 212, the pencil hardness measured in step (iv) is the hardness of the anti-fingerprint coating 212.

[0143] To further demonstrate that the housing 10 provided in this embodiment has superior wear resistance and friction reduction properties, this application conducted wear tests on the friction reduction coating 11 of the first housing 10a in the embodiment shown in FIG4 and the wear block of the comparative embodiment.

[0144] The difference between the comparative embodiment and this embodiment is that in the comparative embodiment, the housing includes a housing body and a wear block, with the wear block fixedly connected to the surface of the housing body. The wear block is made of polyoxymethylene (POM), that is, the wear block is a POM block.

[0145] The test instrument used for wear testing in this embodiment is the Zhongyi MMF-100 reciprocating friction and wear tester.

[0146] Specifically, the wear test of the anti-friction coating 11 can be carried out by the following test method: First, fix the aluminum alloy sheet with the anti-friction coating 11 on the surface onto the wear test table of the wear test machine, and use a 3*3mm flat alloy steel friction head to grind against the anti-friction coating 11. The friction head load is 500g, the single reciprocating cycle wear length is 10mm, and the coating mass loss and wear depth are recorded after 50,000 reciprocating friction cycles.

[0147] Wear tests on wear blocks can be conducted using the following method: First, fix the aluminum alloy sheet with wear blocks on its surface onto the wear test bench of the wear testing machine. Use a 3*3mm flat alloy steel friction head to grind against the wear block. The friction head is loaded with 500g, and the single reciprocating cycle wear length is 10mm. Record the coating quality loss and wear depth after 50,000 reciprocating friction cycles.

[0148] Please refer to Table 1, which is a comparison table of wear test results between the friction-reducing coating 11 of this embodiment and the wear block of the comparative embodiment.

[0149] In the comparative embodiment, under a load of 500g and 50,000 wear cycles, the wear depth of the wear block was 5μm to 8μm, and the wear amount was 0.1g to 0.15g. Furthermore, when a wear test was performed between the wear block and the anti-fingerprint layer, the anti-fingerprint layer was damaged.

[0150] In this embodiment, under a load of 500g and 50,000 wear cycles, the wear depth of the anti-friction coating 11 is 3μm to 7μm, and the wear amount is 0.08g to 0.12g. Furthermore, when a wear test is performed between the anti-friction coating 11 and the anti-fingerprint layer, the anti-fingerprint layer is not damaged.

[0151] The friction-reducing coating 11 provided in this embodiment has better wear resistance than the wear block in the comparative embodiment, and the friction-reducing coating 11 causes less wear on the anti-fingerprint coating 212, or even no significant wear on the anti-fingerprint coating 212. Therefore, the housing 10 provided in this embodiment, by providing the friction-reducing coating 11 on its surface, can improve the wear resistance of the housing 10, and at the same time reduce the friction between the housing 10 and the anti-fingerprint coating 212 of the shaft cover 21. This can reduce or even avoid wear on the anti-fingerprint coating 212, thereby reducing or even avoiding the impact on the appearance of the shaft cover 21 and improving the user experience.

[0152] Table 1. Comparison of wear test results between the anti-friction coating 11 of this embodiment and the wear block of the comparative embodiment.

[0153] This application also provides a method for manufacturing a housing 10. Please refer to Figure 9, which is a flowchart of the manufacturing process of the housing 10 provided in this application.

[0154] The method for manufacturing the housing 10 includes:

[0155] S1: Provide the housing body and clean the housing body;

[0156] S2: A primer layer is applied to the surface of the shell body obtained in step S1 to obtain the second intermediate shell;

[0157] S3: Provide a friction-reducing coating, and spray the friction-reducing coating onto the surface of the second intermediate shell to obtain the first intermediate shell;

[0158] S4: Place the first intermediate shell under ultraviolet light to irradiate it, so that the friction-reducing coating can be cured to form a friction-reducing coating, thus obtaining the shell.

[0159] Please refer to Figure 10, which is a structural schematic diagram of the shell body 12 provided by the manufacturing method shown in Figure 9.

[0160] The housing body 12 is provided with a receiving groove 13. The receiving groove 13 is located in the edge region of the housing body 12 in the X direction. The receiving groove 13 includes a first sub-surface 1211 and a third sub-surface 1213. The first sub-surface 1211 is the bottom wall surface of the receiving groove 13, and the third sub-surface 1213 is the side wall surface of the receiving groove 13. The first sub-surface 1211 is parallel or substantially parallel to the XY plane. The third sub-surface 1213 is connected to one side of the first sub-surface 1211 in the X direction, and the third sub-surface 1213 is connected to the first sub-surface 1211 at an angle.

[0161] It should be noted that the structure of the shell body 12 can be the same as or similar to the structure of the first shell body 12a in Figure 4, or the structure of the shell body 12 can be the same as or similar to the structure of the second shell body 12b in Figure 4. When the structure of the shell body 12 is the same as the structure of the first shell body 12a, the first shell 10a as shown in Figure 4 can be manufactured using the manufacturing method shown in Figure 9. When the structure of the shell body 12 is the same as the structure of the second shell body 12b, the second shell 10b as shown in Figure 4 can be manufactured using the manufacturing method shown in Figure 9.

[0162] In step S1, "cleaning the housing body 12" includes:

[0163] (1) Clean the surface of the housing body 12 with a cleaning agent;

[0164] (2) Wash the shell body 12 obtained in step (1) with water;

[0165] (3) Dry the shell body 12 obtained in step (2) with high pressure oil-free gas.

[0166] In step (1), the surface of the housing body 12 is cleaned with a cleaning agent to remove grease and dirt. To further simplify the manufacturing method, in this embodiment, only the first sub-surface 1211 of the receiving tank 13 is cleaned to remove grease and dirt located on the first sub-surface 1211. In this embodiment, the cleaning agent is ethyl acetate. In other embodiments, the cleaning agent can also be a degreasing agent. Furthermore, the cleaning agent is a neutral degreasing agent to avoid corrosion of the surface of the housing body 12. Here, "neutral degreasing agent" refers to a degreasing solution with a pH value between 6 and 8. Alternatively, the cleaning agent can also be other substances that can remove grease and dirt from the surface of the housing body 12; no specific limitation is made to the cleaning agent here.

[0167] In step (2), the cleaning agent remaining on the surface of the housing body 12 can be removed by washing with water.

[0168] In step (3), the shell body 12 obtained in step (2) is dried by high-pressure oil-free gas, which can remove the water remaining on the surface of the shell body 12.

[0169] In this embodiment, cleaning the housing body 12 removes stains and dust from its surface, allowing the friction-reducing coating 11 to adhere better to its surface. This improves the adhesion of the friction-reducing coating 11 and extends its service life. Furthermore, cleaning the housing body 12 removes stains and dust, preventing defects such as pores from forming the friction-reducing coating 11 and improving its density, smoothness, and uniformity.

[0170] Please refer to Figure 11, which is a schematic diagram of the structure of the second intermediate shell 14 obtained in step S2 of the manufacturing method shown in Figure 9.

[0171] Step S2 includes:

[0172] Provide primer solvent;

[0173] The shell body 12 obtained in step S1 is immersed in the primer solvent so that the primer solvent adheres to the surface of the shell body 12 and forms a primer layer 141 on the surface of the shell body 12.

[0174] Rinse the surface with water to remove any remaining primer solvent, then dry to obtain the second intermediate shell 14.

[0175] The second intermediate shell 14 is the shell body 12 with a primer.

[0176] In the process of "rinsing off residual primer solvent from the surface with water," deionized water can be used to clean the housing body 12 to avoid introducing other impurities into the primer layer 141, thereby preventing any impact on the adhesion and smoothness of the formed anti-friction coating 11. After rinsing with water, the housing body 12 can be dried at 80°C for 1 to 3 minutes to remove residual water from its surface. In other embodiments, the drying temperature can be slightly lower or slightly higher than 80°C. This avoids the drying temperature from affecting the flatness of the housing body 12 and also prevents deformation of the housing body 12.

[0177] In this embodiment, when fabricating the second intermediate shell 14, only the area of ​​the shell body 12 where the primer layer 141 needs to be attached can be immersed in the primer solvent; that is, the first sub-surface 1211 can be immersed in the primer solution. It should be noted that when fabricating the first shell 10a as shown in FIG. 4, the first sub-surface 1211a of the first shell body 12a can be immersed in the primer solvent; and when fabricating the second shell 10b as shown in FIG. 4, the first sub-surface 1211b of the second shell body 12b can be immersed in the primer solvent.

[0178] This saves raw materials and reduces the manufacturing cost of the housing 10 and the foldable terminal 100. It also prevents the primer from adhering to the outer surface of the housing 10 and affecting its appearance. The outer surface of the housing 10 refers to the surface exposed outside the foldable terminal 100. For example, the outer surface of the first housing 10a refers to the second surface 122a, and the outer surface of the second housing 10b refers to the second surface 122b.

[0179] The primer layer 141 comprises one or more of titanate activators, zirconate activators, phosphate activators, and silane coupling agents. In this embodiment, the primer layer 141 is a titanate activator. In this embodiment, by first forming the primer layer 141 on the surface of the housing body 12 and then forming the anti-friction coating 11, the adhesion between the anti-friction coating 11 and the housing body 12 can be improved, thereby extending the service life of the anti-friction coating 11, and consequently extending the service life of the housing 10 and the foldable terminal 100.

[0180] In this embodiment, the thickness of the primer layer 141 in the second intermediate shell 14 is 1μm to 2μm to ensure sufficient adhesion between the formed anti-friction coating 11 and the shell body 12. In other embodiments, the thickness of the primer layer 141 may be less than 1μm or slightly greater than 2μm.

[0181] In step S3, the friction-reducing coating includes a resin, a friction-reducing material, a photoinitiator, a crosslinking agent, a wear-resistant material, and a film-forming aid. In this embodiment, the resin includes polyurethane acrylic resin. The resin in the friction-reducing coating comprises 30 to 55 parts by weight. The friction-reducing material includes one or more of flake-layered graphite, fluorinated graphite, and molybdenum disulfide. In this embodiment, the friction-reducing material includes flake-layered graphite, fluorinated graphite, and molybdenum disulfide. Specifically, the flake-layered graphite in the friction-reducing coating comprises 10 to 20 parts by weight, the fluorinated graphite comprises 2 to 5 parts by weight, and the molybdenum disulfide comprises 25 to 40 parts by weight. The wear-resistant material includes one or more of nano-oxides and metal carbides. The wear-resistant material in the friction-reducing coating comprises 3 to 9 parts by weight.

[0182] It should be noted that the types and weight proportions of resins, friction-reducing materials, and wear-resistant materials can be referred to the previous descriptions, and will not be repeated here.

[0183] The photoinitiator includes one or more of benzoin derivatives, α-hydroxyketone photoinitiators, and acylphosphine oxide photoinitiators. In this embodiment, by adding a photoinitiator to the friction-reducing coating, the cross-linking of resins such as polyurethane acrylic resins can be promoted, thereby increasing the curing rate of the resin and thus improving the production efficiency of the friction-reducing coating 11, that is, improving the production efficiency of the shell 10. In this embodiment, the weight percentage of the photoinitiator in the friction-reducing coating is 2 to 5 parts by weight. In other embodiments, the weight percentage of the photoinitiator can be increased or decreased according to actual conditions.

[0184] The crosslinking agent includes one or more of the following: thiol monomers, acrylic monomers, epoxy monomers, and pentaerythritol ester multifunctional monomers. The crosslinking agent in the friction-reducing coating is 1 to 3 parts by weight. In this embodiment, the crosslinking agent includes a thiol monomer. The functionality of the thiol monomer is 3 to 5. Thiols refer to a class of non-aromatic compounds containing a mercapto functional group (-SH).

[0185] It should be noted that when the bonding resin is polyurethane acrylic resin, by adding thiol monomers to the friction-reducing coating, during the curing process, the mercapto groups (-SH) of the thiol monomers can undergo a free radical addition reaction with the carbon-carbon double bonds (C=C) in the polyurethane acrylic resin under the action of a photoinitiator, forming thioether bonds (-S-). This enables the polyurethane acrylic resin to crosslink and form a dense crosslinked network, thereby improving the hardness and wear resistance of the friction-reducing coating 11. Simultaneously, the thiol monomers can also react with the isocyanate groups (-NCO) in the polyurethane acrylic resin to form thiocarbamate bonds, further enhancing the crosslinking density and mechanical properties of the friction-reducing coating 11.

[0186] Furthermore, in this embodiment, a multifunctional thiol monomer is used as a crosslinking agent, which can further improve the crosslinking degree of the bonding resin and further improve the density of the polyurethane acrylic crosslinking network, thereby giving the bonding resin better mechanical properties, and further improving the hardness and wear resistance of the friction-reducing coating 11.

[0187] In this embodiment, the film-forming aid in the friction-reducing coating is 5 to 10 parts by weight. The film-forming aid includes one or more of the following: benzyl alcohol (BA), ethylene glycol (EG), propylene glycol (PG), hexanediol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (abbreviated as alcohol ester-12), 2-butoxyethanol (EB), propylene glycol monomethyl ether (PM), propylene glycol monoethyl ether, and dipropylene glycol monomethyl ether (DPM).

[0188] In this embodiment, by adding a film-forming aid to the friction-reducing coating, the film formation of the friction-reducing coating can be promoted, that is, the friction-reducing coating can be cured to form a friction-reducing coating 11, thereby improving the manufacturing efficiency of the friction-reducing coating 11 and the shell 10, and reducing the film-forming temperature of the friction-reducing coating 11, that is, reducing the manufacturing temperature of the shell 10.

[0189] In preparing friction-reducing coatings, solvents, resins, photoinitiators, crosslinking agents, friction-reducing materials, wear-resistant materials, and film-forming aids are added to a container and then stirred evenly in a laboratory environment at 25°C. Specifically, a magnetic stirrer can be used at a medium stirring speed to improve the uniformity of the friction-reducing coating.

[0190] The solvent can be an ester solvent, such as ethyl acetate or n-butyl acetate; or a ketone solvent, such as butanone or methyl isobutyl ketone; or an aromatic solvent, such as toluene or xylene. Alternatively, the solvent can be a mixture of multiple compounds.

[0191] In a preferred embodiment, the friction-reducing coating comprises 40 parts by weight of polyurethane acrylic resin, 2 parts by weight of thiol monomer, 3 parts by weight of photoinitiator, 15 parts by weight of flake graphite, 3 parts by weight of fluorinated graphite, 35 parts by weight of nano molybdenum disulfide particles, 7 parts by weight of nano alumina particles, and 7 parts by weight of film-forming aid.

[0192] In other embodiments, the weight proportions of resin, photoinitiator, crosslinking agent, friction-reducing material, wear-resistant material, and film-forming aid may be adjusted according to specific circumstances.

[0193] In step S3, when spraying the friction-reducing coating onto the surface of the housing body 12 obtained in step S2, the friction-reducing coating can be diluted with a solvent at a ratio of 1:2 to 1:4 to obtain a diluted friction-reducing coating. Then, the diluted friction-reducing coating is sprayed onto the housing body 12 with a primer. This improves the uniformity of the friction-reducing coating spraying, thereby improving the uniformity of the formed friction-reducing coating 11.

[0194] Specifically, when spraying diluted friction-reducing coating, the diluted coating can be added to the spray gun first. Then, under conditions of 0.7 MPa air pressure, 1.0 mm nozzle diameter, and 45° spray angle, the friction-reducing coating is sprayed onto the primer-coated housing body 12, allowing the coating to adhere to the primer surface. Multiple spraying cycles can be performed during this process to ensure the thickness and uniformity of the friction-reducing coating adhering to the housing body 12.

[0195] Before step S4, the shell body 12 with the anti-friction coating obtained in step S3 can be baked to remove the organic solvents from the anti-friction coating on the surface of the shell body 12. Specifically, the baking temperature is 80°C and the baking time is 3 to 5 minutes. Alternatively, the baking temperature can be slightly lower or slightly higher than 80°C. This avoids the baking temperature from affecting the flatness of the shell body 12 and also prevents the shell body 12 from deforming.

[0196] In step S4, the baked shell body 12 with the anti-friction coating is placed under an ultraviolet LED light source for irradiation, causing the anti-friction coating to cure and form an anti-friction coating 11, thereby obtaining the shell 10. The wavelength of the ultraviolet LED light source is 365nm–400nm, and the ultraviolet light energy is 700–1000mJ / cm². 2 The ultraviolet light intensity is 100–180 mW / cm². 2 To ensure that the friction-reducing coating has a fast curing speed and a good curing effect, the thickness of the friction-reducing coating 11 is 30μm to 50μm to ensure the wear resistance and adhesion of the friction-reducing coating 11.

[0197] Please refer to Figure 12, which is a structural schematic diagram of the shell 10 manufactured using the method shown in Figure 9.

[0198] In this embodiment, the housing 10 includes a housing body 12, a primer layer 141, and a friction-reducing coating 11. The primer layer 141 is formed on the surface of the housing body 12, and the friction-reducing coating 11 is formed on the surface of the primer layer 141. In this embodiment, by forming the friction-reducing coating 11 on the surface of the housing body 12, the surface friction coefficient of the housing 10 can be reduced, thereby improving the wear resistance of the housing 10.

[0199] When the structure of the housing body 12 is the same as the structure of the first housing body 12a in the embodiment shown in FIG4, the structure of the housing 10 obtained by this embodiment is the same as the structure of the first housing 10a shown in FIG4; when the structure of the housing body 12 is the same as the structure of the second housing body 12b in the embodiment shown in FIG4, the structure of the housing 10 obtained by this embodiment is the same as the structure of the second housing 10b shown in FIG4.

[0200] When the housing 10 obtained in this embodiment is applied to the foldable terminal 100, the coefficient of friction between the housing 10 and the shaft cover 21 is low. In this way, wear on the anti-fingerprint coating 212 formed on the shaft cover 21 can be reduced or even avoided, thereby reducing or even avoiding the impact on the appearance of the shaft cover 21 and improving the user experience.

[0201] It should be noted that in one existing solution, the coefficient of friction between the housing and the bearing cap can be reduced by incorporating a polyoxymethylene (POM) wear block into the housing. However, incorporating the POM wear block into the housing typically involves insert injection molding to form the POM wear block, and CNC (Computerized Numerical Control Machine) technology is required to cut the POM wear block. This results in a complex manufacturing process and high production costs.

[0202] The method for manufacturing the housing 10 provided in this embodiment can form the anti-friction coating 11 on the surface of the housing body 12 by spraying, which is simple and has low manufacturing cost.

[0203] It should be further noted that during the production, assembly, or use of the foldable terminal 100, the flatness of the housing 10 is prone to change, which can lead to unavoidable motion interference between the housing 10 and the shaft cover 21 of the rotating shaft 20, resulting in friction and wear. Furthermore, the housing 10 typically has many precisely sized holes or structural components. When the housing 10 deforms, the shape and size of these holes and structural components will change, thus affecting the assembly accuracy of the foldable terminal 100 and its production.

[0204] The method for manufacturing the housing 10 provided in this embodiment uses polyurethane acrylic resin as the resin, allowing the anti-friction coating to be cured by ultraviolet light irradiation. This reduces the curing temperature of the anti-friction coating, thus lowering the maximum temperature required to manufacture the housing 10. This reduces the risk of heat deformation of the housing 10 and minimizes or even eliminates the impact of excessively high temperatures on the flatness of the housing 10, thereby improving the production yield of the housing 10. Furthermore, it prevents wear between the housing 10 and the shaft cover 21 caused by deformation, further reducing wear between them. It also prevents deformation of the housing 10 from affecting the size and shape of the holes and structural components within the housing 10, improving the assembly accuracy of the foldable terminal 100. In addition, the method for manufacturing the housing 10 provided in this embodiment uses polyurethane acrylic resin as the bonding resin, which improves the flexibility and hardness of the anti-friction coating 11, thereby further improving the wear resistance of the anti-friction coating 11 and further reducing the friction between the anti-friction coating 11 and the shaft cover 21.

[0205] It is understood that the manufacturing method of the housing 10 provided in this embodiment can manufacture the housing 10 with the anti-friction coating 11 at a lower temperature. On the one hand, it can reduce the risk of thermal deformation of the housing 10, thereby reducing or even avoiding the impact of excessive temperature on the flatness of the housing 10. On the other hand, by forming the anti-friction coating 11 on the housing 10, the coefficient of friction between the housing 10 and the shaft cover 21 can be reduced, reducing or even avoiding wear on the anti-fingerprint coating 212 formed on the shaft cover 21, thereby reducing or even avoiding the impact on the appearance of the shaft cover 21 and improving the user experience.

[0206] It should be noted that the housing 10 manufactured using the method provided in this embodiment can be used not only in the folding phone shown in Figure 1, but also in other interfaces involving low-load, low-cycle rotational engagement, such as the hinge of a laptop computer or the hinge of a tablet computer keyboard. No specific limitations are made on the application of the housing 10 here.

[0207] The above are merely some embodiments and implementation methods of this application. The scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A housing for a foldable terminal, the foldable terminal including a pivot, the housing being rotatably connected to the pivot, characterized in that, The housing includes a housing body and a friction-reducing coating. The housing body includes a first surface and a second surface. The first surface and the second surface are disposed opposite to each other along the thickness direction of the housing body. The first surface includes a first sub-surface and a second sub-surface. The first sub-surface and the second sub-surface have the same orientation. The friction-reducing coating comprises a resin and a friction-reducing material, wherein the resin comprises polyurethane acrylic resin and the friction-reducing material comprises graphite and / or molybdenum disulfide; the friction-reducing coating is formed on the first sub-surface; when the foldable terminal is in the unfolded state, the first sub-surface is configured to be opposite to the outer surface of the rotating shaft.

2. The housing according to claim 1, characterized in that, The resin in the friction-reducing coating is 30 to 55 parts by weight, and the friction-reducing material in the friction-reducing coating is 30 to 65 parts by weight.

3. The housing according to claim 2, characterized in that, The friction-reducing material includes graphite, which includes flake-layered graphite and / or fluorinated graphite.

4. The housing according to claim 2, characterized in that, The friction-reducing coating also includes a wear-resistant material, which includes one or more of nano-oxides and metal carbides.

5. The housing according to claim 4, characterized in that, The wear-resistant material includes nano-alumina.

6. The housing according to claim 1, characterized in that, The thickness of the friction-reducing coating is 30μm to 50μm.

7. The housing according to claim 1, characterized in that, The pencil hardness of the friction-reducing coating is 5B to 2B.

8. The housing according to claim 1, characterized in that, The surface friction coefficient of the anti-friction coating is less than 0.

1.

9. The housing according to claim 1, characterized in that, The housing body is provided with a receiving groove, the receiving groove includes a third sub-surface and a first sub-surface, the third sub-surface is connected between the first sub-surface and the second sub-surface; the anti-friction coating is elongated and is disposed on the first sub-surface along the length direction of the housing.

10. The housing according to claim 1, characterized in that, The housing body is provided with a receiving groove, the receiving groove includes a third sub-surface and a first sub-surface, the third sub-surface is connected between the first sub-surface and the second sub-surface; the anti-friction coating includes a plurality of first sub-coatings, the plurality of first sub-coatings are spaced apart on the first sub-surface along the length direction of the housing.

11. A method for manufacturing a shell, characterized in that, include: Provide the housing body; A friction-reducing coating is provided, the friction-reducing coating comprising a resin and a friction-reducing material, the resin comprising a polyurethane acrylic resin, and the friction-reducing material comprising graphite and / or molybdenum disulfide; The anti-friction coating is sprayed onto the surface of the housing body to obtain a first intermediate housing. The first intermediate shell is placed under ultraviolet light to irradiate it, so that the friction-reducing coating is cured to form a friction-reducing coating, thereby obtaining the shell.

12. The method for manufacturing the shell according to claim 11, characterized in that, Before the step of "spraying the anti-friction coating onto the surface of the housing body", the manufacturing method further includes: Provide primer solvent; The shell body is immersed in the primer solvent so that the primer solvent adheres to the surface of the shell body and forms a primer layer on the surface of the shell body to obtain a second intermediate shell; In the step "spraying the anti-friction coating onto the surface of the housing body", the anti-friction coating is sprayed onto the surface of the primer layer.

13. The method for manufacturing the shell according to claim 12, characterized in that, The primer layer includes one or more of carbonate activators, zirconate activators, phosphate activators, and silane coupling agents.

14. The method for manufacturing the shell according to claim 12, characterized in that, Before the step of "immersing the shell body in the primer solvent", the manufacturing method further includes: cleaning the shell body with a cleaning agent and water in sequence, and then drying the shell body with high-pressure oil-free gas.

15. The method for manufacturing the shell according to claim 14, characterized in that, Before the step of "spraying the anti-friction coating onto the surface of the housing body", the manufacturing method further includes: mixing the anti-friction coating with a diluent to obtain a diluted anti-friction coating; "Spraying the anti-friction coating onto the surface of the housing body to obtain a first intermediate housing" includes spraying the diluted anti-friction coating onto the surface of the housing body to obtain the first intermediate housing.

16. The method for manufacturing the shell according to claim 11, characterized in that, The friction-reducing coating also includes a photoinitiator, which includes one or more of benzoin derivatives, α-hydroxy ketone photoinitiators, and acylphosphine oxide photoinitiators.

17. The method for manufacturing the shell according to claim 11, characterized in that, The friction-reducing coating also includes a crosslinking agent, which comprises a thiol monomer with a functionality of 3 to 5.

18. The method for manufacturing the shell according to claim 11, characterized in that, The friction-reducing coating further includes film-forming aids, which include one or more of benzyl alcohol, ethylene glycol, propylene glycol, hexanediol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, and dipropylene glycol monomethyl ether.

19. The method for manufacturing the shell according to claim 11, characterized in that, The friction-reducing coating includes: 30-55 parts by weight of polyurethane acrylic resin; 10-20 parts by weight of flake-layered graphite; 2 to 5 parts by weight of fluorinated graphite; 25-40 parts by weight of molybdenum disulfide; 2-5 parts by weight of photoinitiator; 1 to 3 parts by weight of thiol monomer; 3 to 9 parts by weight of nano-alumina particles; 5 to 10 parts by weight of film-forming aid.

20. A foldable terminal, characterized in that, The device includes a pivot and a housing as described in any one of claims 1 to 10, wherein the housing is rotatably connected to the pivot; when the foldable terminal is in the unfolded state, the first sub-surface is disposed opposite to the outer surface of the pivot; and when the housing is relative to the pivot, the first sub-surface slides along the outer surface of the pivot.

21. The foldable terminal according to claim 20, characterized in that, The rotating shaft includes a shaft cover, a bracket, and an anti-fingerprint coating; the shaft cover is fixedly connected to the bracket, and the anti-fingerprint coating is formed on the surface of the shaft cover facing away from the bracket; and when the housing is relative to the rotating shaft, the anti-friction coating slides along the anti-fingerprint coating.

22. The foldable terminal according to claim 21, characterized in that, The difference between the pencil hardness of the anti-friction coating and the pencil hardness of the anti-fingerprint coating is less than or equal to a pencil hardness range.

Images