Shell, preparation method thereof and electronic equipment

Abstract

The invention provides a shell and a preparation method thereof and electronic equipment, the shell comprises a plastic layer, a treating agent layer and a paint film layer, the treating agent layer is laminated on the surface of the plastic layer, and the paint film layer is laminated on the side, away from the plastic layer, of the treating agent layer; wherein the treating agent layer comprises first resin, second resin and a silane coupling agent, the first resin and the second resin both contain polar groups, the molecular weights of the first resin and the second resin are both larger than or equal to 10,000, and the hydroxyl value of the first resin is smaller than or equal to 20. The shell not only can present an imitation anode matte or highlight effect, but also can reduce the processing and forming cost and shorten the processing time.

Description

Technical Field

[0001] The present application relates to the technical field of electronic equipment, and in particular to a housing and a preparation method thereof, and an electronic device. Background Art

[0002] The housing of existing electronic devices usually uses aluminum alloy as the base material, and uses aluminum alloy as the anode for anodizing treatment to make the housing present a matte effect or a high-gloss effect. However, aluminum alloy is hard in texture and has a high processing cost. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a shell and a preparation method thereof and an electronic device, wherein the shell can not only present an imitation anode matte or high gloss effect, but also reduce the cost of processing and molding and reduce the processing time.

[0004] The embodiment of the present application provides a shell, the shell comprising a plastic layer, a treatment agent layer and a paint film layer, the treatment agent layer is stacked on the surface of the plastic layer, and the paint film layer is stacked on a side of the treatment agent layer away from the plastic layer;

[0005] The treating agent layer comprises a first resin, a second resin and a silane coupling agent, the first resin and the second resin both contain polar groups, the molecular weights of the first resin and the second resin are both ≥10,000, and the hydroxyl value of the first resin is ≤20.

[0006] In the shell provided in the embodiment of the present application, a plastic layer is used as a substrate. On the one hand, the plastic layer can be formed by injection molding, which avoids the problem that the existing aluminum alloy material needs to be processed and formed, and reduces the processing time. On the other hand, the strength and toughness of the plastic layer are well balanced, which can reduce the risk of deformation of the entire electronic device formed by the shell assembly during the drop test.

[0007] In addition, by arranging the treatment agent layer on the plastic layer, through the intermolecular van der Waals force and chemical bond action, the treatment agent layer and the plastic layer have excellent bonding force, which can improve the bonding force between the treatment agent layer and the plastic layer, thereby facilitating the improvement of the excellent bonding force between the paint film layer and the plastic layer, avoiding the paint film layer from falling off the plastic layer, and then facilitating the appearance effect of the electronic device formed by the shell assembly. Specifically, the first resin and the second resin in the treatment agent layer both contain polar groups, which are easy to form chemical bonds with the polar carbonyl bonds contained in the plastic layer, thereby achieving excellent bonding between the paint film layer and the plastic layer. In addition, the larger the molecular weight of the resin, the stronger the van der Waals force. In the treatment agent layer of the embodiment of the present application, the first resin and the second resin with higher molecular weight are used to provide higher van der Waals force, so as to improve the bonding force between the treatment agent layer and the paint film layer, and the bonding force between the treatment agent layer and the plastic layer, thereby achieving excellent bonding between the paint film layer and the plastic layer, and then achieving the appearance effect of the shell. In addition, resins with higher molecular weights are usually harder and prone to collapse. The embodiment of the present application limits the hydroxyl value of the first resin to ≤20, so that the first resin can maintain good toughness while having a higher van der Waals force, so that the adhesion of the paint film layer with more layers on the plastic layer is better, which is conducive to achieving the appearance effect of the shell. In addition, the silicon oxygen bond of the silane coupling agent in the treatment agent layer contains hydrogen bonds, which can form chemical bonds with the polar carbonyl bonds of the plastic layer, which is conducive to further improving the bonding force between the paint film layer and the plastic layer, thereby helping to improve the appearance effect of the shell.

[0008] In addition, by providing a paint film layer on the treatment agent layer, the shell body presents an anode-like matte or high-gloss effect, thereby meeting the appearance effect requirements of the shell body.

[0009] In a possible implementation, the first resin includes acrylic resin, and the second resin includes polyester resin or epoxy resin.

[0010] In a possible implementation, the molecular weight of the acrylic resin is ≥ 40,000, which not only satisfies the hydroxyl value of the acrylic resin to provide good toughness, but also ensures that the acrylic resin provides a higher van der Waals force to enhance the bonding strength between the paint film layer and the plastic layer, thereby facilitating the appearance effect of the shell.

[0011] In a possible implementation, the shell is provided with a microstructure, the microstructure is provided on the surface of the plastic layer facing away from the treatment agent layer, and the microstructure is a protrusion or a depression.

[0012] In a possible implementation manner, the width of the shell is 1 mm to 10 mm.

[0013] In a possible embodiment, the paint film layer includes a color paint layer and a UV topcoat layer, the color paint layer is stacked on the side of the treatment agent layer away from the plastic layer, and the UV topcoat layer is stacked on the surface of the color paint layer away from the plastic layer;

[0014] The color paint layer includes a color paste and a third resin, and the color paste is dispersed in the third resin.

[0015] In a possible embodiment, the color paint layer also includes aluminum powder, which is dispersed in the third resin, and the UV topcoat layer includes the first photocurable resin and matte powder, which is dispersed in the first photocurable resin. By adding aluminum powder to the color paint layer, the aluminum powder has a strong metallic texture, which is conducive to achieving the appearance of different metallic textures of the shell. Specifically, on the one hand, the aluminum powder can be arranged in a directional manner in the third resin, which can achieve the appearance of the shell presenting an anode-like appearance. On the one hand, aluminum powders of different particle sizes and finenesses have different metallic textures, so that the shell presents different metallic textures. On the other hand, the aluminum powder is also easy to be processed into flakes, spheres, etc., so that the shell presents different metallic textures. The appearance effect, while the cost is relatively low. In addition, the aluminum powder is also easy to disperse in the third resin through surface treatment, which is conducive to improving the anode-like appearance of the shell. And the aluminum powder is not easily oxidized in the third resin. Through the use of aluminum powder, color paste and the third resin, the color paint layer presents a fine and bright aluminum powder arrangement and color effect.

[0016] In addition, by adding matte powder to the UV topcoat layer, the paint film layer presents a matte effect. At the same time, by adding the first light-curing resin to the UV topcoat layer, the UV topcoat layer can be cured under light conditions. On the one hand, compared with the natural air-drying curing method, it is conducive to the rapid curing and molding of the UV topcoat layer, saving preparation time, and on the other hand, it avoids the impact of high-temperature baking on the paint film layer.

[0017] In a possible embodiment, the paint film layer further includes a PU primer layer, the PU primer layer is laminated on the surface of the treatment agent layer away from the plastic layer, and the color paint layer is laminated on the surface of the PU primer layer away from the plastic layer;

[0018] The PU primer layer includes polyurethane and a concealing filler, the concealing filler is dispersed in the polyurethane, and the mass fraction of the concealing filler in the PU primer layer is 8% to 25%. By adding a PU primer layer, the PU primer layer has good solubility in the polyurethane by adding a concealing filler to the polyurethane, so that the formed PU primer layer can effectively cover the surface defects of the plastic layer such as floating fibers, which is beneficial to improving the appearance of the shell.

[0019] In a possible embodiment, the paint film layer further includes a PU transition layer and a UV primer layer, the PU transition layer is laminated on the surface of the treatment agent layer away from the plastic layer, the UV primer layer is laminated on the surface of the PU transition layer away from the plastic layer, and the color paint layer is laminated on the surface of the UV primer layer away from the plastic layer;

[0020] Among them, the PU transition layer includes polyurethane and a covering filler, the covering filler is dispersed in the polyurethane, and the mass fraction of the covering filler of the PU transition layer in the PU transition layer is ≤5%, and the UV primer layer includes a second photocurable resin and a covering filler, the covering filler is dispersed in the second photocurable resin, and the mass fraction of the covering filler of the UV primer layer in the UV primer layer is 8% to 25%, and the functionality of the second photocurable resin is lower than that of the first photocurable resin. By adding a PU transition layer and a UV primer layer, the PU transition layer is used to cover the surface defects such as floating fibers of the plastic layer on the one hand, which is beneficial to improve the appearance of the shell, and the polyurethane in the PU transition layer can provide van der Waals force on the other hand, and the mass fraction of the covering filler in the PU transition layer is less than the mass fraction of the covering filler in the UV primer layer, so that it can play a role in connecting the bonding force between the treatment agent layer and the UV primer layer. In addition, the covering filler in the UV primer layer can further cover the surface defects of the plastic layer, thereby further improving the appearance of the shell.

[0021] In a possible implementation, the third resin is a photocurable resin, the functionality of the third resin is lower than that of the first photocurable resin, the paint film layer further comprises a UV primer layer and a metal texture layer, the UV primer layer is stacked on a side of the treatment agent layer away from the plastic layer, the metal texture layer is stacked on a surface of the UV primer layer away from the plastic layer, and the color paint layer is stacked on a side of the metal texture layer away from the plastic layer;

[0022] Among them, the UV primer layer includes a second photocurable resin and a concealing filler, the concealing filler is dispersed in the second photocurable resin, the mass fraction of the concealing filler of the UV primer layer in the UV primer layer is 8% to 25%, and the UV topcoat layer includes a first photocurable resin, and the functionality of the second photocurable resin is lower than the functionality of the first photocurable resin. The concealing filler in the UV primer layer is used to cover the surface defects such as floating fibers of the plastic layer. The photocurable resin in the UV primer layer can be cured and formed under light conditions to avoid the influence of high-temperature baking conditions on the paint film layer. At the same time, the UV primer layer can also improve the plating properties of the metal texture layer, and has excellent bonding with the metal texture layer. In addition, both the color paint layer and the UV topcoat layer use photocurable resins, which can be cured and formed under light conditions while providing the appearance color, further avoiding the influence of high-temperature baking conditions on the paint film layer.

[0023] In a possible implementation, the color paint layer further includes aluminum powder, which is dispersed in the third resin, and the paint film layer further includes a UV intermediate layer, which is laminated on the surface of the metal texture layer away from the plastic layer, and the color paint layer is laminated on the surface of the UV intermediate layer away from the plastic layer;

[0024] The UV intermediate layer includes a third light-curing resin, and the functionality of the third light-curing resin is lower than that of the first light-curing resin. The color paint layer is used to provide fine bright aluminum powder arrangement and color effects. At the same time, by adding a UV intermediate layer between the metal texture layer and the color paint layer, the UV intermediate layer can be cured under light conditions on the one hand, and on the other hand, it can also play a role in connecting the bonding force between the metal in the metal texture layer and the first color paint layer, thereby facilitating the improvement of the adhesion fastness of the color paint layer.

[0025] In a possible implementation, the UV topcoat layer further includes matte powder, and the matte powder is dispersed in the first photocurable resin.

[0026] In a possible implementation, the paint film layer further includes a PU transition layer, which is laminated on the surface of the treatment agent layer away from the plastic layer, and the UV primer layer is laminated on the surface of the PU transition layer away from the plastic layer. By adding the PU transition layer, on the one hand, the surface defects such as floating fibers of the plastic layer are covered, which is beneficial to improving the appearance of the shell, and on the other hand, the polyurethane in the PU transition layer can provide van der Waals force, and the mass fraction of the covering filler in the PU transition layer is less than the mass fraction of the covering filler in the UV primer layer, thereby playing a role in connecting the bonding force between the treatment agent layer and the UV primer layer.

[0027] In a possible embodiment, the paint film layer further includes a PU transition layer, a metal texture layer, a color paste layer, a resin layer and a UV topcoat layer, the PU transition layer is stacked on the surface of the treatment agent layer away from the plastic layer, the metal texture layer is stacked on the surface of the PU transition layer away from the plastic layer, the color paste layer is stacked on the surface of the metal texture layer away from the plastic layer, the resin layer is stacked on the surface of the color paste layer away from the plastic layer, and the UV topcoat layer is stacked on the surface of the resin layer away from the plastic layer;

[0028] The PU transition layer includes acrylic resin and concealing filler, and the concealing filler is dispersed in the acrylic resin. The mass fraction of the concealing filler in the PU transition layer is ≤5%. The concealing filler in the PU transition layer is used to cover the surface defects such as floating fibers of the plastic layer to improve the appearance of the shell. At the same time, the PU transition layer also plays a role in connecting the bonding force between the treatment agent layer and the metal texture layer. In addition, the color paste layer is combined with the metal texture layer to achieve the texture, texture and color effect of the paint film layer. The resin layer plays a role in connecting the bonding force between the color paste layer and the UV topcoat layer. In addition, by setting the UV topcoat layer, the paint film layer is made scratch-resistant, which improves the appearance protection effect of the shell.

[0029] In a possible embodiment, the plastic layer includes a first surface, a second surface, a side surface and a chamfered surface, the first surface and the second surface are arranged opposite to each other along the thickness direction of the plastic layer, and the second surface faces the treatment agent layer, the side surface is located between the first surface and the second surface, and the chamfered surface is connected between the second surface and the side surface. By arranging the chamfered surface between the second surface of the plastic layer facing the treatment agent layer and the side surface, the film material of the treatment agent layer and the paint film layer is facilitated to diffuse along the chamfered surface, thereby facilitating the problem of edge accumulation of the film material.

[0030] In a possible implementation, the chamfered surface is an arc surface, and the radius of the chamfered surface is between 0.1 mm and 0.5 mm. By setting the chamfered surface as an arc surface, the surface of the plastic layer presents a non-right angle design, and the smooth arc surface improves the diffusion effect of the film layer material stacked on the surface of the plastic layer along the arc surface, thereby further improving the problem of edge accumulation of the film layer material.

[0031] In one possible embodiment, the UV topcoat layer includes inorganic particles, the particle size of the inorganic particles is ≤200nm, and the molecular weight of the inorganic particles is ≤120. On the one hand, the inorganic particles are used to improve the wear resistance of the UV topcoat layer. On the other hand, the addition of inorganic particles can improve the viscosity of the material of the UV topcoat layer, which is beneficial to improve the edge accumulation problem of the UV topcoat layer during film formation. In addition, the nano-scale inorganic particles do not affect the transparency of the UV topcoat layer, which is beneficial to presenting the simulated anode appearance effect of the paint film layer. On the other hand, by limiting the molecular weight of the inorganic particles, the precipitation of the inorganic particles in the photocurable resin is avoided, thereby helping to improve the appearance effect of the paint film layer.

[0032] An embodiment of the present application also provides an electronic device, including a functional device and a housing as described above, wherein the functional device is installed in the housing.

[0033] In a possible embodiment, the housing is a shaft decoration, the functional device is a shaft mechanism, and the shaft mechanism is installed on the shaft decoration. In a possible embodiment, the plastic layer in the shaft decoration includes resin and reinforcing material, the reinforcing material is carbon fiber, and the mass fraction of carbon fiber in the plastic layer is 10% to 50%; or the plastic layer includes resin and reinforcing material, the reinforcing material is glass fiber or whisker, and the mass fraction of reinforcing material in the plastic layer is 10% to 70%. In a possible embodiment, the resin includes any one of polyetheretherketone, polyphenylene sulfide, polybutylene terephthalate, polyetherimide and liquid crystal polymer.

[0034] In a possible embodiment, the shell is a mobile phone middle frame, a mobile phone front cover, a laptop top cover, a laptop palm rest or a laptop bottom cover. In a possible embodiment, the plastic layer in the mobile phone middle frame or the mobile phone front cover includes nylon and glass fiber, and the mass fraction of the glass fiber in the plastic layer is 10% to 70%.

[0035] The present application also provides a method for preparing a shell, and the method for preparing a shell includes:

[0036] The plastic layer is prepared by injection molding;

[0037] A treatment agent layer is prepared on the surface of the plastic layer, wherein the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, wherein both the first resin and the second resin contain polar groups, the molecular weights of both the first resin and the second resin are ≥10,000, and the hydroxyl value of the first resin is ≤20;

[0038] preparing a patch, the patch comprising a release film and a paint film layer covering the release film;

[0039] Lay the paint film layer of the patch on the treatment agent layer and remove the release film.

[0040] The method for preparing the shell provided in the embodiment of the present application prepares a paint film layer on a release film to form a patch, and uses the patch to adhere to the treatment agent layer covered on the surface of the plastic layer to transfer the paint film layer to the plastic layer. The preparation process is simple and the preparation efficiency is high.

[0041] The present application also provides a method for preparing a shell, and the method for preparing a shell comprises:

[0042] The plastic layer is prepared by injection molding;

[0043] A treatment agent layer is prepared on the surface of the plastic layer, wherein the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, wherein both the first resin and the second resin contain polar groups, the molecular weights of both the first resin and the second resin are ≥10,000, and the hydroxyl value of the first resin is ≤20;

[0044] A paint film layer is prepared on the surface of the treating agent layer facing away from the plastic layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 A schematic diagram of the structure of an electronic device in an unfolded state provided by an embodiment of the present application;

[0047] Figure 2 for Figure 1 A schematic diagram of the structure of the electronic device shown in the folded state;

[0048] Figure 3 for Figure 1The schematic diagram of the cross-sectional structure of the housing of the electronic device shown is a rotating shaft decoration;

[0049] Figure 4 for Figure 3 A schematic diagram of the three-dimensional structure of the plastic layer in the rotating shaft decorative part shown;

[0050] Figure 5 for Figure 3 A schematic diagram of a first preparation process of a rotating shaft decorative part is shown;

[0051] Figure 6 for Figure 3 A schematic diagram of a second preparation process of the rotating shaft decorative part shown;

[0052] Figure 7 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the first embodiment is shown;

[0053] Figure 8 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the second embodiment is shown;

[0054] Fig. 9 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the third embodiment is shown;

[0055] Fig.10 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the fourth embodiment is shown;

[0056] Fig.11 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the fifth embodiment is shown;

[0057] Fig.12 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the sixth embodiment is shown;

[0058] Fig.13 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the seventh embodiment is shown;

[0059] Fig.14 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the eighth embodiment is shown;

[0060] Fig.15 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration member in the ninth embodiment is shown;

[0061] Fig.16 Schematic diagram of the preparation process of the rotating shaft decoration of the ninth embodiment. DETAILED DESCRIPTION

[0062] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0063] See also Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the electronic device 1 provided in the embodiment of the present application in the unfolded state. Figure 2 for Figure 1 The structure diagram of the electronic device 1 is shown in a folded state.

[0064] In this embodiment, the electronic device 1 is a foldable mobile phone. That is, the electronic device 1 is a mobile phone that can be switched between a folded state and an unfolded state. The electronic device 1 includes a housing and a functional device, and the functional device is mounted on the housing. Exemplarily, the housing is a rotating shaft decoration 1700, and the functional device can be a rotating shaft mechanism 1500. Among them, the outer surface of the housing can be used as the appearance surface of the mobile phone.

[0065] In other embodiments, the electronic device 1 may be a mobile phone, and the shell is a mobile phone middle frame or a mobile phone front shell (A shell), or the electronic device 1 may be a laptop computer (Personal Computer, PC), and the shell is an A shell (top cover), a C shell (palm rest) or a D shell (bottom cover) of the laptop computer.

[0066] It should be understood that the electronic device 1 of this embodiment is an electronic product that can be folded once. In other embodiments, the electronic device 1 can also be an electronic product that can be folded multiple times (more than twice). In this case, the electronic device 1 can include multiple parts, and two adjacent parts can be folded relatively close to each other until the electronic device 1 is in a folded state, and the two adjacent parts can also be unfolded relatively far away from each other until the electronic device 1 is in an unfolded state.

[0067] In this embodiment, the electronic device 1 includes a housing device 1000 and a display screen 3000, and the display screen 3000 is installed on the housing device 1000. Specifically, the housing device 1000 includes a first housing 1100, a second housing 1300, a hinge mechanism 1500, and a hinge decoration 1700. The hinge mechanism 1500 is connected between the first housing 1100 and the second housing 1300 to achieve a rotation connection between the first housing 1100 and the second housing 1300. The hinge decoration 1700 is installed on the outside of the hinge mechanism 1500 and is located between the first housing 1100 and the second housing 1300. The hinge decoration 1700 can cover the internal parts of the hinge mechanism 1500 to improve the appearance consistency and aesthetics of the electronic device 1. The width of the hinge decoration 1700 is generally narrow. For example, the width of the hinge decoration 1700 is D, and D is 1mm to 10mm. In some embodiments, D is 1mm to 5mm.

[0068] The display screen 3000 includes a first display portion 3100, a second display portion 3300 and a bendable portion 3500. The first display portion 3100 is mounted on the first housing 1100, the second display portion 3300 is mounted on the second housing 1300, and the bendable portion 3500 is connected between the first display portion 3100 and the second display portion 3300 and is disposed opposite to the hinge mechanism 1500.

[0069] The first housing 1100 and the second housing 1300 can rotate relative to each other through the hinge mechanism 1500, and the display screen 3000 can follow the movement of the first housing 1100, the second housing 1300 and the hinge mechanism 1500 to achieve mutual switching between the folded state and the unfolded state of the electronic device 1. Figure 1 As shown, the first housing 1100 rotates relative to the second housing 1300 to be relatively unfolded, so that the electronic device 1 is in an unfolded state. At this time, the first display portion 3100, the second display portion 3300 and the bendable portion 3500 are roughly in the same plane, and the angles between the first display portion 3100, the second display portion 3300 and the bendable portion 3500 are all 180 degrees. Figure 2 As shown, the first shell 1100 can also be rotated to a relative position relative to the second shell 1300 so that the electronic device 1 is in a folded state. At this time, the first display part 3100 and the second display part 3300 are arranged opposite to each other, the bendable part 3500 is bent, the first shell 1100 and the second shell 1300 are arranged opposite to each other, and the hinge decoration 1700 is located on the outside of the hinge mechanism 1500 and serves as the appearance surface of the electronic device 1.

[0070] See also Figure 1 , Figure 3 and Figure 4 , Figure 3 for Figure 1 The housing of the electronic device 1 is a schematic cross-sectional structure diagram of a rotating shaft decoration 1700. Figure 4 for Figure 3 A schematic diagram of the three-dimensional structure of the plastic layer 100 in the rotating shaft decoration 1700 is shown.

[0071] In the following embodiments, the shell is used as the rotating shaft decoration 1700 for illustration. The rotating shaft decoration 1700 includes a plastic layer 100, a treatment agent layer 300 and a paint film layer 500. The plastic layer 100 is mounted on the rotating shaft mechanism 1500, the treatment agent layer 300 is stacked on the surface of the plastic layer 100 away from the rotating shaft mechanism 1500, and the paint film layer 500 is stacked on the side of the treatment agent layer 300 away from the plastic layer 100. In this embodiment, the width of the plastic layer 100 is the width of the rotating shaft mechanism 1500. Exemplarily, the width of the plastic layer 100 is 2 mm to 10 mm. In some embodiments, the width of the plastic layer 100 is 2 mm to 5 mm.

[0072] Specifically, the material of the plastic layer 100 includes resin and reinforcing material. Among them, the resin can be exemplified by polyetheretherketone (Poly (Ether-Ether-Ketone), PEEK), polyphenylene sulfide (Polyphenylene Sulfide, PPS), polybutylene terephthalate (Polybutylene Terephthalate, PBT), polyetherimide (Polyetherimide, PEI), or liquid crystal polymer (Li first resin, LCP), etc., and the embodiment of the present application does not specifically limit the material of the resin. The reinforcing material can be exemplified by carbon fiber (Carbon Fiber, CF), glass fiber (Glass Fiber, GF) and whiskers, etc. It can be understood that the role of the reinforcing material is to enhance the strength of the plastic layer 100, and the material added to the resin that can enhance the strength of the plastic layer 100 can be used as a reinforcing material, and the present application does not limit this. In addition, it should be understood that the embodiment of the present application can also choose to add or not add reinforcing materials according to actual needs.

[0073] Exemplarily, the plastic layer 100 in the rotating shaft decoration 1700 includes resin and reinforcing material, the reinforcing material is carbon fiber, and the mass fraction of carbon fiber in the plastic layer 100 is 10% to 50%. Alternatively, the plastic layer 100 in the rotating shaft decoration 1700 includes resin and reinforcing material, the reinforcing material is glass fiber or whisker, and the mass fraction of reinforcing material in the plastic layer 100 is 10% to 70%. The resin in the plastic layer 100 in the rotating shaft decoration 1700 can be any one of polyetheretherketone, polyphenylene sulfide, polybutylene terephthalate, polyetherimide and liquid crystal polymer. For example, the resin in the plastic layer 100 of the shaft decoration 1700 is polyetheretherketone, which is an aromatic crystalline thermoplastic polymer material, and the reinforcing material is carbon fiber, and the mass fraction of the carbon fiber is 10% to 50%. The bending modulus of the formed plastic layer 100 can reach 15Gpa to 22Gpa, the bending strength can reach 290Mpa to 310Mpa, and the tensile strength can reach 180Mpa to 210Mpa.

[0074] In other embodiments, the plastic layer 100 in the mobile phone cover includes nylon and glass fiber, and the mass fraction of the glass fiber in the plastic layer 100 is 10% to 70%. In other embodiments, the plastic layer 100 in the top cover of a laptop computer, the palm rest of a laptop computer, or the bottom cover of a laptop computer includes nylon and whiskers, and the mass fraction of the whiskers in the plastic layer 100 is 10% to 70%.

[0075] See also Figure 4 The outer surface of the plastic layer 100 includes a first surface 101, a second surface 103, a side surface 105 and a chamfered surface 107. The first surface 101 and the second surface 103 are arranged opposite to each other along the thickness direction of the plastic layer 100, the first surface 101 faces the rotating shaft mechanism 1500, and the second surface 103 faces away from the rotating shaft mechanism 1500. The side surface 105 is connected to the side of the first surface 101 facing the second surface 103, and the chamfered surface 107 is connected between the side surface 105 and the second surface 103. In this embodiment, the chamfered surface 107 is an arc surface, and the radius of the chamfered surface 107 is between 0.1 mm and 0.5 mm.

[0076] Specifically, in this embodiment, the side surface 105 includes a first side surface 105a and a second side surface 105b. There are two first side surfaces 105a, each of which extends along the length direction of the rotating shaft decorative member 1700. There are two second side surfaces 105b, each of which extends along the width direction of the rotating shaft decorative member 1700. The two second side surfaces 105b are connected between the two first side surfaces 105a. The chamfered surface 107 includes a first chamfered portion 107a and a second chamfered portion 107b. The first chamfered portion 107a is connected between the second surface 103 and the first side surface 105a, and the radius of the first chamfered portion 107a is between 0.1mm and 0.5mm. The second chamfered portion 107b is connected between the second surface 103 and the second side surface 105b, and the radius of the second chamfered portion 107b is between 0.1mm and 0.5mm.

[0077] The hinge decoration 1700 is provided with a microstructure 1710, and the microstructure 1710 is provided on the surface of the hinge decoration 1700 facing the hinge mechanism 1500. Among them, the microstructure 1710 is used to adapt to the surface of the hinge mechanism 1500, so that the hinge decoration 1700 and the hinge mechanism 1500 fit more tightly when assembled. Exemplarily, the microstructure 1710 is concave or convex. In the embodiment of the present application, the microstructure 1710 is provided on the first surface 101 of the plastic layer 100. Among them, the strength and toughness of the plastic layer 100 are well balanced, which can simultaneously meet the requirements of the injection molding microstructure 1710 and reduce the risk of deformation of the electronic device 1 during the drop test.

[0078] The treatment agent layer 300 is stacked on the second surface 103 of the plastic layer 100 away from the microstructure 1710. Specifically, the material of the treatment agent layer 300 includes a first resin, a second resin and a silane coupling agent, the first resin and the second resin both contain polar groups, the molecular weights of the first resin and the second resin are both ≥10,000, and the hydroxyl value of the first resin is ≤20. In this embodiment, the first resin is an acrylic resin, and the molecular weight of the acrylic resin is ≥40,000. In some embodiments, the glass transition temperature Tg of the acrylic resin is ≤60°C, so that the acrylic resin has the advantages of good toughness and small shrinkage force, which is conducive to improving the adhesion of the paint film layer 500 to the plastic layer 100. In this embodiment, the second resin is a polyester resin or an epoxy resin, and the molecular weight of the second resin is ≥10,000. The paint film layer 500 is used to provide an appearance effect for the rotating shaft decorative part 1700. Exemplarily, the paint film layer 500 can present a matte effect or a high-gloss effect.

[0079] The rotating shaft decoration 1700 provided in the embodiment of the present application uses the plastic layer 100 as the substrate. On the one hand, the plastic layer 100 can form a microstructure 1710 by injection molding, which avoids the problem that the existing aluminum alloy material needs to be processed to form the microstructure 1710, and reduces the processing time of the microstructure 1710. On the other hand, the strength and toughness of the plastic layer 100 are well balanced, which reduces the risk of deformation of the electronic device 1 in the drop test. In addition, by arranging the treatment agent layer 300 on the plastic layer 100, the treatment agent layer 300 and the plastic layer 100 have excellent bonding strength through the intermolecular van der Waals force and chemical bond action, which can improve the bonding strength between the treatment agent layer 300 and the plastic layer 100, thereby facilitating the improvement of the excellent bonding strength between the paint film layer 500 and the plastic layer 100, avoiding the paint film layer 500 from falling off the plastic layer 100, and further facilitating the improvement of the appearance effect of the electronic device 1. Specifically, the first resin and the second resin in the treatment agent layer 300 both contain polar groups, which are easy to form chemical bonds with the polar carbonyl bonds contained in the plastic layer 100, thereby achieving excellent bonding between the paint film layer 500 and the plastic layer 100. In addition, the larger the molecular weight of the resin, the stronger the van der Waals force. The treatment agent layer 300 of the embodiment of the present application uses the first resin and the second resin with a higher molecular weight to provide a higher van der Waals force to enhance the bonding between the treatment agent layer 300 and the paint film layer 500, and the bonding between the treatment agent layer 300 and the plastic layer 100, thereby achieving excellent bonding between the paint film layer 500 and the plastic layer 100, and further achieving the appearance effect of the rotating shaft decorative part 1700. In addition, resins with higher molecular weights are usually harder and prone to layer collapse. The embodiment of the present application limits the hydroxyl value of the first resin to ≤20, so that the first resin can maintain good toughness while having a higher van der Waals force, so that the paint film layer 500 with more layers has a better adhesion effect on the plastic layer 100, thereby facilitating the appearance effect of the rotating shaft decorative part 1700. In addition, the silicon oxygen bond of the silane coupling agent in the treatment agent layer 300 contains hydrogen bonds, which can form chemical bonds with the polar carbonyl bonds of the plastic layer 100, which is conducive to further improving the bonding force between the treatment agent layer 300 and the plastic layer 100, thereby facilitating the adhesion effect of the paint film layer 500 on the plastic layer 100, and further facilitating the appearance effect of the rotating shaft decorative part 1700.

[0080] In addition, by providing a paint film layer 500 on the treating agent layer 300 , the rotating shaft decoration 1700 can present an anode-like matte or high-gloss effect, thereby meeting the appearance effect requirements of the rotating shaft decoration 1700 .

[0081] In addition, the first resin in the treatment agent layer 300 includes acrylic resin, and the polar hydroxyl group contained in the acrylic resin is easy to react with the polar carbonyl bond in the plastic layer 100 to form a chemical bond, thereby facilitating the improvement of the bonding force between the paint film layer 500 and the plastic layer 100. The second resin includes polyester resin or epoxy resin, and the polar ester group in the polyester resin or the epoxy bond contained in the epoxy resin has a lone pair of electrons and a polar bond, which are easy to form a chemical bond with the polar carbonyl bond in the plastic layer 100, thereby facilitating the improvement of the bonding force between the paint film layer 500 and the plastic layer 100.

[0082] In addition, when the width of the rotating shaft decorative part 1700 is narrow, the film material on the plastic layer 100 is prone to edge accumulation. The embodiment of the present application sets a chamfered surface 107 between the second surface 103 of the plastic layer 100 facing the treatment agent layer 300 and the side surface 105, which is conducive to the diffusion of the film material of the treatment agent layer 300 and the paint film layer 500 along the chamfered surface 107, thereby helping to avoid the problem of edge accumulation of the film material. In addition, by setting the chamfered surface 107 as an arc surface, so that the surface of the plastic layer 100 presents a non-right angle design, the smooth arc surface improves the diffusion effect of the film material stacked on the surface of the plastic layer 100 along the arc surface, thereby further improving the problem of edge accumulation of the film material.

[0083] See also Figure 5 , Figure 5 for Figure 3 The first preparation process diagram of the rotating shaft decoration piece 1700 is shown. The embodiment of the present application also provides a first preparation method of the rotating shaft decoration piece 1700, comprising the following steps:

[0084] Step S1, preparing a plastic layer 100 by injection molding;

[0085] Step S2, preparing a treatment agent layer 300 on the surface of the plastic layer 100;

[0086] Step S3 , preparing a paint film layer 500 on the side of the treating agent layer 300 facing away from the plastic layer 100 .

[0087] Wherein, step S1 comprises: taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400°C to 450°C, the temperature of the mold is 180°C to 220°C, and the injection pressure is 2000Mpa to 2500Mpa. After the plastic layer 100 is injection molded, the material of the plastic layer 100 is cleaned in time to avoid crystallization and carbonization of the barrel containing the material of the plastic layer 100, which leads to the need to disassemble the barrel screw.

[0088] Step S2 includes: coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. Exemplarily, the baking time at 70° C. to 85° C. is 10 minutes to 20 minutes to achieve leveling, surface drying and curing of the treatment agent layer 300.

[0089] See also Figure 6 , Figure 6 for Figure 3 The second preparation process diagram of the rotating shaft decoration piece 1700 is shown. The embodiment of the present application also provides a second preparation method of the rotating shaft decoration piece 1700, comprising the following steps:

[0090] Step S1, preparing a plastic layer 100 by injection molding, and preparing a treatment agent layer 300 on the surface of the plastic layer 100;

[0091] Step S2, preparing a patch, the patch comprising a release film and a paint film layer 500 covering the release film;

[0092] Step S3, attach the paint film layer 500 of the patch toward the treatment agent layer 300, and remove the release film; wherein step S1 and step S2 can be interchanged. Exemplarily, the release film is a polyethylene terephthalate (PET) film or a polycarbonate (PC) film.

[0093] Wherein, in step S3, bonding can be performed in a vacuum bonding device.

[0094] In the embodiment of the present application, a paint film layer 500 is prepared on a release film to form a patch, and the patch is bonded to a treatment agent layer 300 covering the surface of a plastic layer 100 to transfer the paint film layer 500 to the plastic layer 100. The preparation process is simple and the preparation efficiency is high.

[0095] The structure of the rotating shaft decoration 1700 is described in detail below in conjunction with specific embodiments, wherein the paint film layer 500 in the first to fifth embodiments presents a matte effect, and the paint film layer 500 in the sixth to ninth embodiments presents a high-gloss effect. It should be noted that, in the following embodiments, the "first UV topcoat layer 20", "UV base coat 50", "UV intermediate layer 80", and "second UV topcoat layer 90" all contain photocurable resins, and the photocurable resins can be cured and formed under ultraviolet (UV) light. The "PU base coat 30" and the "PU transition layer 40" both contain polyurethane (PU). The "polyurethane" involved in this application can be prepared by reacting a hydroxyl compound with a curing agent. Hydroxyl compounds include but are not limited to acrylic resins, hydroxyl-containing polyester resins, hydroxyl-containing epoxy resins, and the like. The curing agent includes but is not limited to HDI (Hexamethylene Diisocyanate), XDI (m-Xylylene Diisocyanate), PDI (pentamethylene diisocyanate), IPDI (Isophorone Diisocyanate), and the like.

[0096] See also Figure 7 , Figure 7 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the first embodiment is shown.

[0097] The paint film layer 500 in the rotating shaft decoration 1700 of the first embodiment includes a first color paint layer 10 and a first UV topcoat layer 20. The first color paint layer 10 is laminated on the surface of the treatment agent layer 300 away from the plastic layer 100, and the first UV topcoat layer 20 is laminated on the surface of the first color paint layer 10 away from the plastic layer 100. Among them, the thickness of the treatment agent layer 300 in the rotating shaft decoration 1700 of this embodiment is 3μm to 12μm, the thickness of the first color paint layer 10 is 2μm to 10μm, and the thickness of the first UV topcoat layer 20 is 10μm to 25μm. Among them, the "UV topcoat layer" refers to a film layer containing a photocurable resin that can be cured and formed by ultraviolet light (Ultraviolet, UV).

[0098] Specifically, the first color paint layer 10 includes aluminum powder, color paste and a third resin, and the particle size of the aluminum powder is 5μm to 8μm. Among them, the mass fraction of aluminum powder in the first color paint layer 10 is 2% to 6%. The color paste is a nano-scale color paste, and the average particle size of the color paste is ≤300nm, which has the effects of high color intensity and good transparency. When selecting the third resin, a resin with a better effect of arranging aluminum powder can be selected. Exemplarily, the third resin is an electroplated silver resin, the main component of which is an acrylic modified polymer with a molecular weight of ≥70,000.

[0099] When preparing the first color paint layer 10, the third resin can be mixed with a volatile solvent to form a third resin solution, and then the aluminum powder and the color paste are mixed with the third resin solution to form the material of the first color paint layer 10, and then the first color paint layer 10 is prepared by electroplating. Exemplarily, the solid content of the third resin in the third resin solution can be 6% to 15%. Among them, the volatile solvent can be acetone or ethyl ester, which has a strong volatilization effect and is conducive to the rapid film formation of the first color paint layer 10. By adjusting the type of volatile solvents with different volatilization rates and the proportion of the volatile solvent in the first color paint layer 10, the fluidity and leveling of the first color paint layer 10 can be balanced, so that the first color paint layer 10 can be prevented from having edge accumulation, and the problem of easy edge accumulation when preparing the first color paint layer 10 on the narrow edge plastic layer 100 can be solved.

[0100] The first UV topcoat layer 20 includes matt powder and a first photocurable resin, wherein the matt powder is dispersed in the first photocurable resin, and the functionality of the first photocurable resin is 6 to 9. The addition of matt powder can, on the one hand, make the paint film layer 500 present a matte effect, and on the other hand, can improve the viscosity of the material of the first UV topcoat layer 20, which is beneficial to improve the problem of edge accumulation of the material of the first UV topcoat layer 20 during film formation. Exemplarily, the average particle size of the matt powder is ≤2μm, and a matt powder with a maximum particle size of ≤15μm can be formed in combination with a grinding process, so that the first UV topcoat layer 20 has a higher transparency and presents a high-quality anti-anodizing effect. Exemplarily, the matt powder can include gas-phase silica of different particle sizes.

[0101] Exemplarily, the first photocurable resin is a polyurethane acrylic resin, and the functionality of the polyurethane acrylic resin is 6 to 9. It can not only be cured under the action of ultraviolet light, but also has good dispersibility for matte powder, and can also meet the requirements of scratch resistance and hardness, and play a protective role. Exemplarily, the molecular weight of the first photocurable resin in the first UV topcoat layer 20 is greater than 3000, which can effectively improve the problem of edge accumulation of the film material, and thus solve the problem of edge accumulation of the rotating shaft decorative part 1700 with a narrow width. It is understandable that in the preparation of the first UV topcoat layer 20, the material of the first UV topcoat layer 20 can also be dispersed in a volatile solvent to form a raw material, and the advantage of the strong volatilization of the volatile solvent is used to enable the first UV topcoat layer 20 to form a film quickly.

[0102] The rotating shaft decoration piece 1700 provided in the first embodiment is prepared according to the following steps:

[0103] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0104] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0105] Step S3, electroplating the material of the first color paint layer 10 on the surface of the treatment agent layer 300 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the first color paint layer 10;

[0106] The material of the first UV topcoat layer 20 is applied to the surface of the first color paint layer 10 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800-1000mJ / cm 2 The first UV topcoat layer 20 is formed by irradiating the surface with ultraviolet light and curing the surface.

[0107] In the rotating shaft decoration 1700 provided in the first embodiment, by adding aluminum powder to the first color paint layer 10, and by using aluminum powder, color paste and the third resin in combination, the first color paint layer 10 presents a fine and bright aluminum powder arrangement and color effect. In addition, by adding matte powder to the first UV topcoat layer 20, the paint film layer 500 presents a matte effect. At the same time, by adding the first light-curing resin to the first UV topcoat layer 20, the first UV topcoat layer 20 can be cured under light conditions. On the one hand, compared with the natural air-drying curing method, it is conducive to the rapid curing and molding of the first UV topcoat layer 20, saving preparation time, and on the other hand, it avoids the influence of high-temperature baking on the paint film layer 500.

[0108] See also Figure 8 , Figure 8 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the second embodiment is shown.

[0109] The difference between the shaft decoration 1700 of the second embodiment and the shaft decoration 1700 of the first embodiment is that the paint film layer 500 of the shaft decoration 1700 of the second embodiment also includes a PU primer layer 30 , and the PU primer layer 30 is stacked between the treatment agent layer 300 and the first color paint layer 10 .

[0110] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the second embodiment includes a PU primer layer 30, a first color paint layer 10 and a first UV topcoat layer 20 stacked in sequence, the PU primer layer 30 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the first color paint layer 10 is stacked on the surface of the PU primer layer 30 away from the plastic layer 100, and the first UV topcoat layer 20 is stacked on the surface of the first color paint layer 10 away from the plastic layer 100. Among them, the thickness of the treatment agent layer 300 in the rotating shaft decoration 1700 of this embodiment is 3μm to 12μm, the thickness of the PU primer layer 30 is 3μm to 12μm, the thickness of the first color paint layer 10 is 2μm to 10μm, and the thickness of the first UV topcoat layer 20 is 10μm to 25μm.

[0111] Among them, the first color paint layer 10 and the first UV topcoat layer 20 are respectively the same as the first color paint layer 10 and the first UV topcoat layer 20 of the first embodiment. The PU base coating 30 includes polyurethane and a covering filler, the covering filler is dispersed in the polyurethane, and the mass fraction of the covering filler in the PU base coating 30 is 8% to 25%. Exemplarily, the covering filler can be exemplified by matte powder, nano-silicon dioxide and talcum powder. Exemplarily, the fineness of the covering filler is ≤25μm, and the smaller the fineness of the covering filler, the smoother the PU base coating 30 is, which can reduce the uneven drop, which is beneficial to the appearance effect of the aluminum powder in the first color paint layer 10 arranged on the plane of the PU base coating 30, thereby facilitating the appearance effect of the rotating shaft decorative part 1700.

[0112] The rotating shaft decoration piece 1700 provided in the second embodiment is prepared according to the following steps:

[0113] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0114] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0115] Step S3, coating the material of the PU primer layer 30 on the surface of the treatment agent layer 300 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the PU primer layer 30;

[0116] Electroplating the material of the first color paint layer 10 on the surface of the PU primer layer 30 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the first color paint layer 10;

[0117] The material of the first UV topcoat layer 20 is applied to the surface of the first color paint layer 10 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The first UV topcoat layer 20 is formed by irradiating the surface with ultraviolet light and curing the surface.

[0118] Compared with the first embodiment, the shaft decoration 1700 provided in the second embodiment is additionally provided with a PU base coating 30. The PU base coating 30 is formed by adding a masking filler into the polyurethane. The masking filler has good solubility in the polyurethane, so that the formed PU base coating 30 can effectively cover the surface defects such as floating fibers of the plastic layer 100, which is beneficial to improving the appearance of the shaft decoration 1700.

[0119] See also Fig. 9 , Fig. 9 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the third embodiment is shown.

[0120] The difference between the shaft decoration 1700 of the third embodiment and the shaft decoration 1700 of the first embodiment is that the paint film layer 500 of the shaft decoration 1700 of the third embodiment also includes a PU transition layer 40 and a UV primer layer 50, and the PU transition layer 40 and the UV primer layer 50 are sequentially stacked between the treating agent layer 300 and the first color paint layer 10.

[0121] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the third embodiment includes a PU transition layer 40, a UV primer layer 50, a first color paint layer 10 and a first UV topcoat layer 20 stacked in sequence. The PU transition layer 40 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the UV primer layer 50 is stacked on the surface of the PU transition layer 40 away from the plastic layer 100, the first color paint layer 10 is stacked on the surface of the PU transition layer 40 away from the plastic layer 100, and the first UV topcoat layer 20 is stacked on the surface of the first color paint layer 10 away from the plastic layer 100. Among them, the thickness of the treating agent layer 300 in the shaft decoration 1700 of this embodiment is 3μm~12μm, the thickness of the PU transition layer 40 is 3μm~10μm, the thickness of the UV primer layer 50 is 8μm~20μm, the thickness of the first color paint layer 10 is 2μm~10μm, and the thickness of the first UV topcoat layer 20 is 10μm~25μm.

[0122] The PU transition layer 40 includes polyurethane and a concealing filler, the concealing filler is dispersed in the polyurethane, and the mass fraction of the concealing filler in the PU transition layer 40 is ≤5%. The PU transition layer 40 mainly plays a connecting role between the upper and lower parts, and can prevent the UV primer layer 50 from penetrating into the treatment agent layer 300. At the same time, the concealing filler in the PU transition layer 40 can also play a role in covering the defects of the plastic layer 100. In this embodiment, the raw materials of the polyurethane in the PU transition layer 40 include acrylic resin and a curing agent. The acrylic resin is a low-hydroxy acrylic resin, and the hydroxyl value of the acrylic resin is ≤20, which reacts quickly with the curing agent, forms a film quickly, and dries quickly.

[0123] The UV primer 50 includes a second photocurable resin and a concealing filler, the concealing filler is dispersed in the second photocurable resin, and the mass fraction of the concealing filler in the UV primer 50 is 8% to 25%. Exemplarily, the concealing filler may include matte powder, nano-scale silica, and talcum powder. Exemplarily, the fineness of the concealing filler is ≤25μm, and the smaller the fineness of the concealing filler, the smoother the UV primer 50 is, which can reduce the uneven drop, and is conducive to the appearance effect of the aluminum powder in the first color paint layer 10 arranged on the plane of the UV primer 50, thereby facilitating the appearance effect of the rotating shaft decorative part 1700. Among them, the functionality of the second photocurable resin is less than the functionality of the first photocurable resin in the first UV topcoat layer 20, and a lower curing energy can be used for photocuring. Exemplarily, the second photocurable resin is polyurethane, and the functionality of polyurethane is 1 to 5.

[0124] The rotating shaft decoration piece 1700 provided in the third embodiment is prepared according to the following steps:

[0125] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0126] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0127] Step S3, coating the material of the PU transition layer 40 on the surface of the treatment agent layer 300 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the PU transition layer 40;

[0128] The UV primer 50 material is coated on the surface of the PU transition layer 40 away from the plastic layer 100, and then baked at 55℃~65℃ for 5 minutes, and then heated with 400mJ / cm 2 -800mJ / cm 2The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0129] Electroplating the material of the first color paint layer 10 on the surface of the UV primer layer 50 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the first color paint layer 10;

[0130] The material of the first UV topcoat layer 20 is applied to the surface of the first color paint layer 10 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The first UV topcoat layer 20 is formed by irradiating the surface with ultraviolet light and curing the surface.

[0131] Compared with the first embodiment, the shaft decoration 1700 provided in the third embodiment is additionally provided with a PU transition layer 40 and a UV primer layer 50, wherein the PU transition layer 40 is used to cover the surface defects such as floating fibers of the plastic layer 100, which is beneficial to improve the appearance of the shaft decoration 1700, and the polyurethane in the PU transition layer 40 can provide van der Waals force, and the mass fraction of the covering filler in the PU transition layer 40 is less than the mass fraction of the covering filler in the UV primer layer 50, which plays a role in connecting the bonding force between the treatment agent layer 300 and the UV primer layer 50. In addition, the covering filler in the UV primer layer 50 can further cover the surface defects of the plastic layer 100, thereby further improving the appearance of the shaft decoration 1700.

[0132] See also Fig.10 , Fig.10 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the fourth embodiment is shown.

[0133] The difference between the shaft decoration 1700 of the fourth embodiment and the shaft decoration 1700 of the first embodiment lies in that the paint film layer 500 of the shaft decoration 1700 of the fourth embodiment also includes a UV primer layer 50, a metallic texture layer 60 and a second color paint layer 70, and the composition of the second color paint layer 70 is different from the composition of the first color paint layer 10 in the shaft decoration 1700 of the first embodiment.

[0134] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the fourth embodiment includes a UV primer layer 50, a metal texture layer 60, a second color paint layer 70 and a first UV topcoat layer 20 stacked in sequence. The UV primer layer 50 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the metal texture layer 60 is stacked on the surface of the UV primer layer 50 away from the plastic layer 100, the second color paint layer 70 is stacked on the surface of the metal texture layer 60 away from the plastic layer 100, and the first UV topcoat layer 20 is stacked on the surface of the second color paint layer 70 away from the plastic layer 100. Among them, the thickness of the treating agent layer 300 in the shaft decoration 1700 of this embodiment is 3μm~12μm, the thickness of the UV primer layer 50 is 8μm~20μm, the thickness of the metal texture layer 60 is 10nm~500nm, the thickness of the second color paint layer 70 is 2μm~10μm, and the thickness of the first UV topcoat layer 20 is 10μm~25μm.

[0135] The composition of the UV primer layer 50 is the same as that of the UV primer layer 50 of the third embodiment. The metal texture layer 60 is used to provide a metal texture. Exemplarily, the metal texture layer 60 includes a metal material. Exemplarily, the metal texture layer 60 can be prepared by electroplating. In this embodiment, the material of the metal texture layer 60 is indium. In other embodiments, the material of the metal texture layer 60 can also be other materials with a metal texture, and the present application does not limit this.

[0136] The second color paint layer 70 includes a third resin and a color paste, and the third resin is a photocurable resin. Exemplarily, the color paste is a nano color paste, that is, the particles of the pigment in the color paste are nanometer-sized. In this embodiment, the functionality of the third resin is 1 to 5. Exemplarily, the photocurable resin is an acrylic resin, and the functionality of the acrylic resin is 1 to 5. The shrinkage force is low during the photocuring process, which can improve the bonding force between the second color paint layer 70 and the metal texture layer 60.

[0137] The rotating shaft decoration piece 1700 provided in the fourth embodiment is prepared according to the following steps:

[0138] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0139] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0140] Step S3: Cover the UV primer 50 material on the surface of the treatment agent layer 300 away from the plastic layer 100, then bake at 55°C to 65°C for 5 minutes, and then use 800-1000mJ / cm 2 The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0141] Using NCVM (Non conductive vacuum metallization) process to electroplate the material of the metal texture layer 60 on the surface of the UV primer layer 50 away from the plastic layer 100 to form the metal texture layer 60;

[0142] The material of the second color paint layer 70 is coated on the surface of the metal texture layer 60 away from the plastic layer 100, and then baked at 55℃~65℃ for 5 minutes, and then heated with 400mJ / cm 2 -800mJ / cm 2 The second color paint layer 70 is formed by irradiating with ultraviolet light and photocuring;

[0143] The material of the first UV topcoat layer 20 is applied to the surface of the second color paint layer 70 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The first UV topcoat layer 20 is formed by irradiating the surface with ultraviolet light and curing the surface.

[0144] Compared with the first embodiment, in the rotating shaft decoration 1700 provided in the fourth embodiment, the covering filler in the UV primer 50 is used to cover the surface floating fibers and other defects of the plastic layer 100. The light-curable resin in the UV primer 50 can be cured under light conditions to avoid the influence of high-temperature baking conditions on the paint film layer 500. At the same time, the UV primer 50 can also improve the plating property of the metal texture layer 60, and has excellent bonding strength with the metal texture layer 60. In addition, the second color paint layer 70 and the first UV topcoat layer 20 are both made of light-curable resin, which can be cured under light conditions while providing the appearance color, further avoiding the influence of high-temperature baking conditions on the paint film layer 500.

[0145] In addition, the matte powder in the first UV topcoat layer 20 can be combined with a grinding process to form a matte powder with a maximum particle size of ≤15μm, so that the first UV topcoat layer 20 has higher transparency, thereby being able to show the metallic texture effect of the metallic texture layer 60, thereby improving the appearance of the shaft decoration 1700.

[0146] See also Fig.11 , Fig.11 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the fifth embodiment is shown.

[0147] The difference between the shaft decoration 1700 of the fifth embodiment and the shaft decoration 1700 of the fourth embodiment is that the paint film layer 500 of the shaft decoration 1700 of the fifth embodiment also includes a UV intermediate layer 80 and a first color paint layer 10, and the first color paint layer 10 replaces the second color paint layer 70 of the fourth embodiment.

[0148] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the fifth embodiment includes a UV primer layer 50, a metal texture layer 60, a UV intermediate layer 80, a first color paint layer 10 and a first UV topcoat layer 20 which are stacked in sequence. The UV primer layer 50 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the metal texture layer 60 is stacked on the surface of the UV primer layer 50 away from the plastic layer 100, the UV intermediate layer 80 is stacked on the surface of the metal texture layer 60 away from the plastic layer 100, the first color paint layer 10 is stacked on the surface of the UV intermediate layer 80 away from the plastic layer 100, and the first UV topcoat layer 20 is stacked on the surface of the first color paint layer 10 away from the plastic layer 100. Among them, the thickness of the treating agent layer 300 in the shaft decoration 1700 of this embodiment is 3μm~12μm, the thickness of the UV primer layer 50 is 8μm~20μm, the thickness of the metal texture layer 60 is 10nm~500nm, the thickness of the UV intermediate layer 80 is 2μm~10μm, the thickness of the first color paint layer 10 is 3μm~12μm, and the thickness of the first UV topcoat layer 20 is 10μm~25μm.

[0149] Among them, the UV primer layer 50, the metal texture layer 60 and the first UV topcoat layer 20 are respectively the same as the UV primer layer 50, the metal texture layer 60 and the first UV topcoat layer 20 of the fourth embodiment, and the first color paint layer 10 is the same as the first color paint layer 10 of the first embodiment. The UV intermediate layer 80 includes a third photocurable resin, and the functionality of the third photocurable resin is lower than the functionality of the first photocurable resin in the first UV topcoat layer 20. Exemplarily, the third photocurable resin in the UV intermediate layer 80 is an acrylic resin, and the functionality of the acrylic resin is 1 to 5, and it can be cured using a relatively low curing energy.

[0150] The rotating shaft decoration piece 1700 provided in the fifth embodiment is prepared according to the following steps:

[0151] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0152] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0153] Step S3: Cover the UV primer 50 material on the surface of the treatment agent layer 300 away from the plastic layer 100, and then bake at 55°C to 65°C for 5 minutes, and then use 400mJ / cm 2 -800mJ / cm 2 The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0154] Using NCVM (Non conductive vacuum metallization) process to electroplate the material of the metal texture layer 60 on the surface of the UV primer layer 50 away from the plastic layer 100 to form the metal texture layer 60;

[0155] Electroplating the material of the first color paint layer 10 on the surface of the metal texture layer 60 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the first color paint layer 10;

[0156] The material of the first UV topcoat layer 20 is applied to the surface of the first color paint layer 10 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The first UV topcoat layer 20 is formed by irradiating the surface with ultraviolet light and curing the surface.

[0157] Compared with the fourth embodiment, in the rotating shaft decoration 1700 provided in the fifth embodiment, the first color paint layer 10 is used to provide fine bright aluminum powder arrangement and color effect, and at the same time, a UV intermediate layer 80 is added between the metal texture layer 60 and the first color paint layer 10. On the one hand, the UV intermediate layer 80 can be cured under light conditions, and on the other hand, it can also play a role in connecting the bonding force between the metal in the metal texture layer 60 and the first color paint layer 10, thereby helping to improve the adhesion fastness of the first color paint layer 10.

[0158] See also Fig.12 , Fig.12 for Figure 3 The shown diagram is a cross-sectional structural diagram of the rotating shaft decoration 1700 in the sixth embodiment.

[0159] The difference between the rotating shaft decoration 1700 of the sixth embodiment and the rotating shaft decoration 1700 of the fourth embodiment is that the paint film layer 500 of the rotating shaft decoration 1700 of the sixth embodiment adopts the second UV topcoat layer 90 to replace the first UV topcoat layer 20 of the fourth embodiment.

[0160] Specifically, the paint film layer 500 in the rotating shaft decoration 1700 of the sixth embodiment includes a UV primer layer 50, a metal texture layer 60, a second color paint layer 70, and a second UV topcoat layer 90. The UV primer layer 50 is laminated on the surface of the treatment agent layer 300 away from the plastic layer 100, the metal texture layer 60 is laminated on the surface of the UV primer layer 50 away from the plastic layer 100, the second color paint layer 70 is laminated on the surface of the metal texture layer 60 away from the plastic layer 100, and the second UV topcoat layer 90 is laminated on the surface of the second color paint layer 70 away from the plastic layer 100. Among them, the thickness of the treating agent layer 300 in the shaft decoration 1700 of this embodiment is 3μm~12μm, the thickness of the UV primer layer 50 is 8μm~20μm, the thickness of the metal texture layer 60 is 10nm~500nm, the thickness of the second color paint layer 70 is 2μm~10μm, and the thickness of the second UV topcoat layer 90 is 10μm~25μm.

[0161] Among them, the second UV topcoat layer 90 includes a first photocurable resin, and the functionality of the first photocurable resin is 6 to 9. Compared with the first UV topcoat layer 20, the second UV topcoat layer 90 does not contain matte powder and presents a high-gloss effect. Exemplarily, the first photocurable resin is a polyurethane acrylic resin, and the functionality of the polyurethane acrylic resin is 6 to 9. In the present embodiment, the second UV topcoat layer 90 also includes inorganic particles, the particle size of the inorganic particles is ≤200nm, and the molecular weight of the inorganic particles is ≤120. Exemplarily, the inorganic particles are nano-scale silica or alumina. On the one hand, the inorganic particles are used to improve the wear resistance of the second UV topcoat layer 90. On the other hand, the addition of inorganic particles can improve the viscosity of the material of the second UV topcoat layer 90, which is beneficial to improve the edge accumulation problem of the second UV topcoat layer 90 during film formation. Exemplarily, the mass fraction of the inorganic particles in the second UV topcoat layer 90 is less than 1%, which ensures that the inorganic filler improves the edge accumulation problem of the second UV topcoat layer 90 without affecting the transparency of the second UV topcoat layer 90, thereby improving the appearance of the paint film layer 500. In addition, the nano-scale inorganic particles do not affect the transparency of the second UV topcoat layer 90, which is conducive to presenting the anode-like appearance of the paint film layer 500. On the other hand, by limiting the molecular weight of the inorganic particles, it is avoided that the use of large molecular weight inorganic particles (such as zirconium dioxide or glass beads) is precipitated in the photocurable resin, thereby improving the appearance of the paint film layer 500.

[0162] The rotating shaft decoration piece 1700 provided in the sixth embodiment is prepared according to the following steps:

[0163] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0164] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 minutes to 20 minutes to obtain the treatment agent layer 300;

[0165] Step S3: Cover the UV primer 50 material on the surface of the treatment agent layer 300 away from the plastic layer 100, and then bake at 55°C to 65°C for 5 minutes, and then use 400mJ / cm 2 -800mJ / cm 2 The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0166] Using NCVM (Non conductive vacuum metallization) process to electroplate the material of the metal texture layer 60 on the surface of the UV primer layer 50 away from the plastic layer 100 to form the metal texture layer 60;

[0167] The material of the second color paint layer 70 is coated on the surface of the metal texture layer 60 away from the plastic layer 100, and then baked at 55℃~65℃ for 5 minutes, and then heated with 400mJ / cm 2 -800mJ / cm 2 The second color paint layer 70 is formed by irradiating with ultraviolet light and photocuring;

[0168] The material of the second UV topcoat layer 90 is applied to the surface of the second color paint layer 70 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The ultraviolet light is irradiated and photocured to form a second UV topcoat layer 90.

[0169] Compared with the fourth embodiment, in the shaft decoration 1700 of the sixth embodiment, the second UV topcoat layer 90 does not contain matte powder, and the color matching of the metal texture layer 60 and the second color paint layer 70 makes the shaft decoration 1700 present a high-gloss effect.

[0170] See also Fig.13 , Fig.13 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the seventh embodiment is shown.

[0171] The difference between the rotating shaft decoration piece 1700 of the seventh embodiment and the rotating shaft decoration piece 1700 of the sixth embodiment lies in that the paint film layer 500 of the rotating shaft decoration piece 1700 of the seventh embodiment further includes a PU transition layer 40 .

[0172] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the seventh embodiment includes a PU transition layer 40, a UV primer layer 50, a metal texture layer 60, a second color paint layer 70 and a second UV topcoat layer 90 stacked in sequence. The PU transition layer 40 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the UV primer layer 50 is stacked on the surface of the PU transition layer 40 away from the plastic layer 100, the metal texture layer 60 is stacked on the surface of the PU transition layer 40 away from the plastic layer 100, the second color paint layer 70 is stacked on the surface of the metal texture layer 60 away from the plastic layer 100, and the second UV topcoat layer 90 is stacked on the surface of the second color paint layer 70 away from the plastic layer 100. In the rotating shaft decoration 1700 of this embodiment, the thickness of the treatment agent layer 300 is 3 μm to 12 μm, the thickness of the PU transition layer 40 is 3 μm to 10 μm, the thickness of the UV primer layer 50 is 8 μm to 20 μm, the thickness of the metal texture layer 60 is 10 nm to 500 nm, the thickness of the second color paint layer 70 is 2 μm to 10 μm, and the thickness of the second UV topcoat layer 90 is 10 μm to 25 μm. The PU transition layer 40 has the same composition as the PU transition layer of the third embodiment.

[0173] The rotating shaft decoration piece 1700 provided in the seventh embodiment is prepared according to the following steps:

[0174] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0175] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 minutes to 20 minutes to obtain the treatment agent layer 300;

[0176] Step S3, coating the material of the PU transition layer 40 on the surface of the treatment agent layer 300 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the PU transition layer 40;

[0177] The UV primer 50 material is coated on the surface of the PU transition layer 40 away from the plastic layer 100, and then baked at 55℃~65℃ for 5 minutes, and then heated with 400mJ / cm 2 -800mJ / cm 2 The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0178] Using NCVM (Non conductive vacuum metallization) process to electroplate the material of the metal texture layer 60 on the surface of the UV primer layer 50 away from the plastic layer 100 to form the metal texture layer 60;

[0179] The material of the second color paint layer 70 is coated on the surface of the metal texture layer 60 away from the plastic layer 100, and then baked at 55℃~65℃ for 5 minutes, and then heated with 400mJ / cm 2 -800mJ / cm 2 The second color paint layer 70 is formed by irradiating with ultraviolet light and photocuring;

[0180] The material of the second UV topcoat layer 90 is applied to the surface of the second color paint layer 70 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The ultraviolet light is irradiated and photocured to form a second UV topcoat layer 90.

[0181] Compared with the sixth embodiment, in the shaft decoration 1700 of the seventh embodiment, by adding a PU transition layer 40, on the one hand, the surface defects such as floating fibers of the plastic layer 100 are covered, which is beneficial to improving the appearance effect of the shaft decoration 1700, and on the other hand, the polyurethane in the PU transition layer 40 can provide van der Waals force, and the mass fraction of the covering filler in the PU transition layer 40 is less than the mass fraction of the covering filler in the UV primer layer 50, thereby playing a role in connecting the bonding force between the treatment agent layer 300 and the UV primer layer 50.

[0182] See also Fig.14 , Fig.14 for Figure 3 The shown diagram is a cross-sectional structural diagram of the rotating shaft decoration 1700 in the eighth embodiment.

[0183] The difference between the rotating shaft decoration piece 1700 of the eighth embodiment and the fifth embodiment is that the paint film layer 500 of the rotating shaft decoration piece 1700 of the eighth embodiment adopts the second UV topcoat layer 90 to replace the first UV topcoat layer 20 of the fourth embodiment.

[0184] Specifically, the paint film layer 500 of the rotating shaft decoration 1700 of the eighth embodiment includes a UV primer layer 50, a metal texture layer 60, a UV intermediate layer 80, a first color paint layer 10 and a second UV topcoat layer 90 stacked in sequence. The UV primer layer 50 is stacked on the surface of the treatment agent layer 300 away from the plastic layer 100, the metal texture layer 60 is stacked on the surface of the UV primer layer 50 away from the plastic layer 100, the UV intermediate layer 80 is stacked on the surface of the metal texture layer 60 away from the plastic layer 100, the first color paint layer 10 is stacked on the surface of the UV intermediate layer 80 away from the plastic layer 100, and the first UV topcoat layer 20 is stacked on the surface of the first color paint layer 10 away from the plastic layer 100. In the rotating shaft decoration 1700 of this embodiment, the thickness of the treatment agent layer 300 is 3 μm to 12 μm, the thickness of the UV primer layer 50 is 8 μm to 20 μm, the thickness of the metal texture layer 60 is 10 nm to 500 nm, the thickness of the UV intermediate layer 80 is 2 μm to 10 μm, the thickness of the first color paint layer 10 is 3 μm to 12 μm, and the thickness of the second UV topcoat layer 90 is 10 μm to 25 μm. The second UV topcoat layer 90 has the same composition as the second UV topcoat layer 90 in the sixth embodiment.

[0185] The rotating shaft decoration piece 1700 provided in the eighth embodiment is prepared according to the following steps:

[0186] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding, the temperature of the material of the plastic layer 100 is 400° C. to 450° C., the temperature of the mold is 180° C. to 220° C., and the injection pressure is 2000 MPa to 2500 MPa.

[0187] Step S2, coating the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the treatment agent layer 300;

[0188] Step S3: Cover the UV primer 50 material on the surface of the treatment agent layer 300 away from the plastic layer 100, and then bake at 55°C to 65°C for 5 minutes, and then use 400mJ / cm 2 -800mJ / cm 2 The UV light is irradiated to form a UV primer layer 50 through photocuring;

[0189] Using NCVM (Non conductive vacuum metallization) process to electroplate the material of the metal texture layer 60 on the surface of the UV primer layer 50 away from the plastic layer 100 to form the metal texture layer 60;

[0190] Electroplating the material of the first color paint layer 10 on the surface of the metal texture layer 60 away from the plastic layer 100, and then baking at 70° C. to 85° C. for 10 to 20 minutes to obtain the first color paint layer 10;

[0191] The material of the second UV topcoat layer 90 is applied to the surface of the first color paint layer 10 away from the plastic layer 100, and then baked at 55°C to 65°C for 5 minutes, and then heated with 800mJ / cm 2 -1000mJ / cm 2 The ultraviolet light is irradiated and photocured to form a second UV topcoat layer 90.

[0192] Compared with the fifth embodiment, in the shaft decoration 1700 of the eighth embodiment, the second UV topcoat layer 90 does not contain matte powder, and the color matching of the metal texture layer 60 and the second color paint layer 70 makes the shaft decoration 1700 present a high-gloss effect.

[0193] See also Fig.15 , Fig.15 for Figure 3 The cross-sectional structure diagram of the rotating shaft decoration 1700 in the ninth embodiment is shown.

[0194] The paint film layer 500 in the rotating shaft decoration 1700 of the ninth embodiment includes a PU transition layer 40, a metal texture layer 60, a color paste layer 92, a resin layer 93 and a second UV topcoat layer 90. The PU transition layer 40 is laminated on the surface of the treatment agent layer 300 away from the plastic layer 100, the metal texture layer 60 is laminated on the surface of the PU transition layer 40 away from the plastic layer 100, the color paste layer 92 is laminated on the surface of the metal texture layer 60 away from the plastic layer 100, the resin layer 93 is laminated on the surface of the color paste layer 92 away from the plastic layer 100, and the second UV topcoat layer 90 is laminated on the surface of the resin layer 93 away from the plastic layer 100. Among them, the thickness of the treating agent layer 300 in the shaft decoration 1700 of this embodiment is 5μm~20μm, the thickness of the PU transition layer 40 is 2μm~10μm, the thickness of the metal texture layer 60 is 20nm~500nm, the thickness of the color paste layer 92 is 5μm~20μm, the thickness of the resin layer 93 is 3μm~15μm, and the thickness of the second UV topcoat layer 90 is 3μm~15μm.

[0195] Among them, the color paste layer 92 includes acrylic resin and color paste. In this embodiment, the hydroxyl value of the acrylic resin is ≤20, so that the acrylic resin has good toughness, so that the resin layer 93 and the second UV topcoat layer 90 have better adhesion effect. The resin layer 93 includes acrylic resin, and the functionality of the acrylic resin is 1 to 5, which plays a role in connecting the bonding force between the color paste layer 92 and the second UV topcoat layer 90. At the same time, the curing energy is low and it is easier to form a film. The second UV topcoat layer 90 has the same composition as the second UV topcoat layer 90 in the sixth embodiment above, which not only presents a high-gloss effect, but also plays a protective effect.

[0196] See also Fig.16 , Fig.16 FIG. 1 is a schematic diagram of the preparation process of the rotating shaft decoration piece 1700 of the ninth embodiment. The rotating shaft decoration piece 1700 of the ninth embodiment is prepared according to the following steps:

[0197] Step S1, taking the material of the plastic layer 100 and placing it in a mold for injection molding to obtain the plastic layer 100, the temperature of the material of the plastic layer 100 is 400°C to 450°C, the temperature of the mold is 180°C to 220°C, and the injection pressure is 2000Mpa to 2500Mpa; covering the material of the treatment agent layer 300 on the surface of the plastic layer 100, and then placing it at 70°C to 85°C and baking it for 10 minutes to 20 minutes to obtain the treatment agent layer 300;

[0198] Step S2, taking the release film 96, and sequentially stacking the second UV topcoat layer 90, the resin layer 93, the color paste layer 92, the metal texture layer 60 and the PU transition layer 40 on the surface of the release film 96 to prepare the patch 700;

[0199] Step S3 , attach the paint film layer 500 of the patch 700 toward the treatment agent layer 300 , and remove the release film 96 .

[0200] Exemplarily, in step S2, the material of the release film 96 is a PET (Polyethylene terephthalate, thermoplastic polyester resin) film or a PC (Polycarbonate, polycarbonate) film. In other embodiments, the material of the release film 96 can also be other materials that are easy to remove the paint film layer 500, and the present application does not limit this. In this embodiment, the thickness of the release film 96 is 150μm to 200μm.

[0201] In the rotating shaft decoration 1700 of the ninth embodiment, the covering filler in the PU transition layer 40 is used to cover the surface floating fibers and other defects of the plastic layer 100 to improve the appearance of the rotating shaft decoration 1700. At the same time, the PU transition layer 40 also plays a role in connecting the bonding force between the treatment agent layer 300 and the metal texture layer 60. In addition, the color paste layer 92 is combined with the metal texture layer 60 to achieve the texture, texture and color effect of the paint film layer 500. The resin layer 93 uses a low-functional acrylic resin, which plays a role in connecting the bonding force between the color paste layer 92 and the second UV topcoat layer 90. In addition, by setting the second UV topcoat layer 90, the paint film layer 500 is scratch-resistant, which improves the appearance protection effect of the rotating shaft decoration 1700.

[0202] Effect Example

[0203] The film thickness analysis and adhesion performance test of the shaft decoration 1700 of the first to ninth embodiments were performed by glue-filling and slicing. Then, the shaft decoration 1700 of the first to ninth embodiments was boiled in 80°C water for 30 minutes, and the appearance of the shaft decoration 1700 was observed.

[0204] The experimental results show that the adhesion of the film layer in the rotating shaft decoration 1700 of the first embodiment to the ninth embodiment is ≥4B, and the appearance of the rotating shaft decoration 1700 does not change after boiling. The experimental results show that the treatment agent layer 300 is provided in the rotating shaft decoration 1700 provided in the embodiment of the present application to improve the bonding force between the paint film layer 500 and the plastic layer 100.

[0205] The embodiment of the present application also studies the effects of different parameters such as the molecular weight of the photocurable resin used in the paint film layer 500, the molecular weight of the polyurethane, the solvent system used in each film layer, the matte powder content and inorganic particles on improving the film layer edge accumulation problem. The experimental results are shown in Table 1.

[0206] Table 1 Effect of different parameters in the paint film layer 500 on improving the edge accumulation problem of the film layer

[0207]

[0208] Specifically, the embodiments of the present application also study the effect of the molecular weight of the photocurable resin used in the first UV topcoat layer 20, the UV primer layer 50, the UV intermediate layer 80 and the second UV topcoat layer 90 in the first to ninth embodiments on improving the edge accumulation problem of the film layer. During the experiment, photocurable resins with a molecular weight of less than 1000, photocurable resins with a molecular weight of 1000 to 3000, and photocurable resins with a molecular weight of more than 3000 were selected respectively. The experimental results show that the use of photocurable resins with a molecular weight of more than 3000 can effectively balance the fluidity and leveling of the film layer, and has the best effect in improving the edge accumulation, thereby solving the problem of edge accumulation that is prone to occur when the paint film layer 500 is set on a narrow shaft decorative part 1700.

[0209] The present application also studies the effect of the molecular weight of the polyurethane resin used in the PU primer layer 30 and the PU transition layer 40 in the first to ninth embodiments on the improvement of the film edge accumulation problem. During the experiment, polyurethane resins with a molecular weight of less than 40,000, a molecular weight of 40,000 to 70,000, and a molecular weight of >70,000 were selected. The experimental results show that polyurethane resins with a molecular weight of ≥40,000 can meet the effect of improving the film edge accumulation, among which polyurethane with a molecular weight of >70,000 can effectively balance the fluidity and leveling of the film layer, and has the best effect of improving the film edge accumulation, thereby solving the problem of easy edge accumulation when the paint film layer 500 is set on the narrow shaft decorative part 1700.

[0210] The present application also studies the effect of the solvent system used in each film layer of the paint film layer 500 in the first to ninth embodiments on improving the film layer edge accumulation problem. Specifically, the materials of each film layer with solvents having different evaporation rates are used, and the experimental results show that the use of a fast-drying volatile solvent can effectively balance the fluidity and leveling of the film layer, and has the best effect on improving the film layer edge accumulation, thereby solving the problem of edge accumulation when the paint film layer 500 is set on a narrow shaft decorative part 1700.

[0211] The present application also studies the effect of the amount of matt powder added to the first UV topcoat layer 20 in the matt topcoat system of the first to fifth embodiments on improving the edge accumulation problem of the first UV topcoat layer 20. During the experiment, the matt powder was taken as an example of fumed silica, and the edge accumulation improvement effect of matt powder with a mass fraction of 3%, 4% and 5% in the first UV topcoat layer 20 was verified. The experimental results show that the addition of matt powder can effectively balance the fluidity and leveling of the first UV topcoat layer 20. The greater the proportion of matt powder added to the first UV topcoat layer 20, the better the effect of improving the edge accumulation problem of the first UV topcoat layer 20, thereby solving the problem of edge accumulation when the paint film layer 500 is set on the narrow shaft decorative part 1700. However, the higher the content of matt powder in the first UV topcoat layer 20, the more it affects the gloss of the first UV topcoat layer 20. The addition ratio of matt powder can be selected according to the actual demand for gloss.

[0212] The present application also studies the effect of the inorganic particles used in the second UV topcoat layer 90 in the high-gloss topcoat system of the sixth to ninth embodiments on improving the edge accumulation problem of the second UV topcoat layer 90. During the experiment, the inorganic particles were used as an example of nano-scale silica, and the edge accumulation improvement effect of the inorganic fillers with mass fractions of 0.5%, 1% and 1.5% in the second UV topcoat layer 90 was verified. The experimental results show that the addition of inorganic particles can effectively balance the fluidity and leveling of the second UV topcoat layer 90, thereby solving the problem of edge accumulation when the paint film layer 500 is set on the narrow shaft decorative part 1700. The greater the proportion of inorganic particles added to the second UV topcoat layer 90, the better the effect of improving the edge accumulation in the second UV topcoat layer 90. However, when the content of inorganic particles in the second UV topcoat layer 90 is ≥1%, it will affect the transmittance of the second UV topcoat layer 90. The mass fraction of inorganic particles in the second UV topcoat layer 90 is less than 1%, which can ensure that the inorganic filler improves the edge accumulation problem of the second UV topcoat layer 90 without affecting the transmittance of the second UV topcoat layer 90, which is beneficial to improving the appearance of the paint film layer 500.

[0213] What is disclosed above is only a preferred embodiment of the present application, and it certainly cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A housing, characterized in that: The shell comprises a plastic layer, a treatment agent layer and a paint film layer, wherein the treatment agent layer is stacked on the surface of the plastic layer, and the paint film layer is stacked on a side of the treatment agent layer away from the plastic layer; Wherein, the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, and both the first resin and the second resin contain polar groups; The paint film layer includes a color paint layer and a UV topcoat layer, the color paint layer is stacked on the side of the treatment agent layer away from the plastic layer, and the UV topcoat layer is stacked on the surface of the color paint layer away from the plastic layer, wherein the color paint layer includes a color paste and a third resin, and the color paste is dispersed in the third resin.

2. The housing according to claim 1, characterized in that The first resin includes acrylic resin, and the second resin includes polyester resin or epoxy resin.

3. The housing according to claim 2, characterized in that: The molecular weight of the acrylic resin is ≥40,000.

4. The housing according to claim 1, characterized in that The shell is provided with a microstructure, and the microstructure is arranged on the surface of the plastic layer away from the treatment agent layer, and the microstructure is convex or concave.

5. The housing according to claim 1, characterized in that The width of the shell is 1 mm to 10 mm.

6. The housing according to any one of claims 1 to 5, characterized in that: The color paint layer further includes aluminum powder, which is dispersed in the third resin; the UV topcoat layer includes a first photocurable resin and matte powder, which is dispersed in the first photocurable resin.

7. The housing according to claim 6, characterized in that The paint film layer further comprises a PU primer layer, the PU primer layer is laminated on the surface of the treatment agent layer away from the plastic layer, and the color paint layer is laminated on the surface of the PU primer layer away from the plastic layer; The PU base coating layer comprises polyurethane and a covering filler, the covering filler is dispersed in the polyurethane, and the mass fraction of the covering filler in the PU base coating layer is 8% to 25%.

8. The housing according to claim 6, characterized in that The paint film layer further comprises a PU transition layer and a UV primer layer, wherein the PU transition layer is laminated on the surface of the treatment agent layer away from the plastic layer, the UV primer layer is laminated on the surface of the PU transition layer away from the plastic layer, and the color paint layer is laminated on the surface of the UV primer layer away from the plastic layer; Among them, the PU transition layer includes polyurethane and a covering filler, the covering filler is dispersed in the polyurethane, and the mass fraction of the covering filler of the PU transition layer in the PU transition layer is ≤5%. The UV primer layer includes a second photocurable resin and a covering filler, the covering filler is dispersed in the second photocurable resin, the mass fraction of the covering filler of the UV primer layer in the UV primer layer is 8% to 25%, and the functionality of the second photocurable resin is lower than the functionality of the first photocurable resin.

9. The housing according to claim 1, characterized in that: The third resin is a light-curing resin, and the paint film layer further comprises a UV primer layer and a metal texture layer, wherein the UV primer layer is stacked on a side of the treatment agent layer away from the plastic layer, the metal texture layer is stacked on a surface of the UV primer layer away from the plastic layer, and the color paint layer is stacked on a side of the metal texture layer away from the plastic layer; Wherein, the UV primer layer includes a second photocurable resin and a covering filler, the covering filler is dispersed in the second photocurable resin, the mass fraction of the covering filler of the UV primer layer in the UV primer layer is 8% to 25%, the UV topcoat layer includes a first photocurable resin, the functionality of the second photocurable resin is lower than the functionality of the first photocurable resin, and the functionality of the third resin is lower than the functionality of the first photocurable resin.

10. The housing according to claim 9, characterized in that The color paint layer further includes aluminum powder, which is dispersed in the third resin; the paint film layer further includes a UV intermediate layer, which is laminated on the surface of the metal texture layer away from the plastic layer; and the color paint layer is laminated on the surface of the UV intermediate layer away from the plastic layer; The UV intermediate layer includes a third photocurable resin, and the functionality of the third photocurable resin is lower than that of the first photocurable resin.

11. The housing according to claim 9 or 10, characterized in that: The UV topcoat layer further includes matte powder, and the matte powder is dispersed in the first photocurable resin.

12. The housing according to claim 9, characterized in that The paint film layer further comprises a PU transition layer, which is laminated on the surface of the treating agent layer away from the plastic layer, and the UV primer layer is laminated on the surface of the PU transition layer away from the plastic layer.

13. The housing according to any one of claims 1 to 5, characterized in that: The plastic layer includes a first surface, a second surface, a side surface and a chamfered surface. The first surface and the second surface are arranged opposite to each other along the thickness direction of the plastic layer, and the second surface faces the treatment agent layer. The side surface is located between the first surface and the second surface, and the chamfered surface is connected between the second surface and the side surface.

14. The housing according to claim 13, characterized in that The chamfered surface is an arc surface, and the radius of the chamfered surface is between 0.1 mm and 0.5 mm.

15. The housing according to any one of claims 1 to 5, characterized in that: The UV topcoat layer comprises inorganic particles, the particle size of the inorganic particles is ≤200nm, and the molecular weight of the inorganic particles is ≤120.

16. A housing, characterized in that: The shell comprises a plastic layer, a treatment agent layer and a paint film layer, wherein the treatment agent layer is stacked on the surface of the plastic layer, and the paint film layer is stacked on a side of the treatment agent layer away from the plastic layer; Wherein, the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, and both the first resin and the second resin contain polar groups; The paint film layer comprises a PU transition layer, a metal texture layer, a color paste layer, a resin layer and a UV topcoat layer, wherein the PU transition layer is laminated on the surface of the treatment agent layer away from the plastic layer, the metal texture layer is laminated on the surface of the PU transition layer away from the plastic layer, the color paste layer is laminated on the surface of the metal texture layer away from the plastic layer, the resin layer is laminated on the surface of the color paste layer away from the plastic layer, and the UV topcoat layer is laminated on the surface of the resin layer away from the plastic layer; The PU transition layer comprises acrylic resin and a covering filler, wherein the covering filler is dispersed in the acrylic resin, and the mass fraction of the covering filler in the PU transition layer is ≤5%.

17. The housing according to claim 16, characterized in that The first resin includes acrylic resin, and the second resin includes polyester resin or epoxy resin.

18. The housing according to claim 17, characterized in that The molecular weight of the acrylic resin is ≥40,000.

19. The housing according to claim 16, characterized in that The shell is provided with a microstructure, and the microstructure is arranged on the surface of the plastic layer away from the treatment agent layer, and the microstructure is convex or concave.

20. The housing according to claim 16, wherein: The width of the shell is 1 mm to 10 mm.

21. The housing according to any one of claims 16 to 20, characterized in that The plastic layer includes a first surface, a second surface, a side surface and a chamfered surface. The first surface and the second surface are arranged opposite to each other along the thickness direction of the plastic layer, and the second surface faces the treatment agent layer. The side surface is located between the first surface and the second surface, and the chamfered surface is connected between the second surface and the side surface.

22. The housing according to claim 21, characterized in that The chamfered surface is an arc surface, and the radius of the chamfered surface is between 0.1 mm and 0.5 mm.

23. The housing according to any one of claims 16 to 20, characterized in that The UV topcoat layer comprises inorganic particles, the particle size of the inorganic particles is ≤200nm, and the molecular weight of the inorganic particles is ≤120.

24. An electronic device, characterized in that: The invention comprises a functional device and a shell, wherein the shell is the shell as described in any one of claims 1 to 15 or the shell as described in any one of claims 16 to 23, and the functional device is installed in the shell.

25. The electronic device according to claim 24, characterized in that: The shell is a rotating shaft decoration, the functional device is a rotating shaft mechanism, and the rotating shaft mechanism is installed on the rotating shaft decoration.

26. The electronic device according to claim 24, characterized in that: The shell is a mobile phone middle frame, a mobile phone front cover, a top cover of a notebook computer, a palm rest of a notebook computer or a bottom cover of a notebook computer.

27. A method for preparing a shell, characterized in that: The shell is a shell according to any one of claims 1 to 15 or a shell according to any one of claims 16 to 23, and the preparation method of the shell comprises: The plastic layer is prepared by injection molding; Preparing a treatment agent layer on the surface of the plastic layer, wherein the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, wherein both the first resin and the second resin contain polar groups; preparing a patch, wherein the patch comprises a release film and a paint film layer covering the release film; The paint film layer of the patch is laminated to the treatment agent layer, and the release film is removed.

28. A method for preparing a shell, characterized in that: The shell is a shell according to any one of claims 1 to 15 or a shell according to any one of claims 16 to 23, and the preparation method of the shell comprises: The plastic layer is prepared by injection molding; Preparing a treatment agent layer on the surface of the plastic layer, wherein the treatment agent layer comprises a first resin, a second resin and a silane coupling agent, wherein both the first resin and the second resin contain polar groups; A paint film layer is prepared on the surface of the treating agent layer facing away from the plastic layer.

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