A substrate for a housing, a housing, and an electronic device

Abstract

The present disclosure relates to a shell base, a shell and an electronic device, and relates to the technical field of electronic devices. The shell base comprises a body and a functional layer arranged on at least one side of the body, and the functional layer comprises a first paint film layer, the first paint film layer being coated by a first coating material, and the first viscosity value of the first viscosity of the first coating material is within a first preset range. The present disclosure controls the first viscosity value of the first viscosity of the first coating material within the first preset range to control the fluidity of the first coating material, which is beneficial to improve the uniformity of the thickness of the first paint film layer and reduce appearance defects such as frame printing, cloth printing, oil accumulation and the like, and plays a protective and aesthetic role for the shell.

Description

Technical Field

[0001] This disclosure relates to the field of electronic device technology, and more particularly to a substrate for a housing, a housing, and an electronic device. Background Technology

[0002] With advancements in communication technology, mobile phones and other electronic devices have become indispensable tools for social interaction and entertainment in people's daily lives. To adapt to market demands and cater to the trend of personalization, the casings of electronic devices have also seen more diverse designs. Therefore, it is necessary to continuously optimize the aesthetics of electronic device casings. Summary of the Invention

[0003] To overcome the problems existing in the related technologies, this disclosure provides a substrate for a housing, a housing, and an electronic device.

[0004] According to a first aspect of the present disclosure, a substrate for a housing is provided, the substrate including a body and a functional layer disposed on at least one side of the body, the functional layer including a first paint film layer, the first paint film layer being coated with a first coating material, the viscosity value of the first viscosity of the first coating material being within a first preset range.

[0005] In some embodiments of this disclosure, the first preset range is 28.3-31.7 mPa·s.

[0006] In some embodiments of this disclosure, the first coating comprises a first main component, which comprises the following raw materials in parts by weight:

[0007] 20-50 parts by weight of multifunctional polyurethane acrylate;

[0008] 4-10 parts by weight of 2-functionality polyurethane acrylate;

[0009] 5-10 parts by weight of thermoplastic acrylic resin;

[0010] 0-4 parts by weight of multifunctional UV-curable monomer.

[0011] In some embodiments of this disclosure, the multifunctional polyurethane acrylate includes trifunctional polyurethane acrylate, quadrifunctional polyurethane acrylate, and nonfunctional polyurethane acrylate in a weight ratio of 0.67-3.60:0.67-3.00:1.

[0012] In some embodiments of this disclosure, the first main component further includes 1-8 parts by weight of a photoinitiator.

[0013] In some embodiments of this disclosure, the photoinitiator includes a first-band photoinitiator and a second-band photoinitiator in a weight ratio of 6.2-40.0:1, wherein the first band is smaller than the second band.

[0014] In some embodiments of this disclosure, the first main component further includes:

[0015] Leveling agent 0.1-0.5 parts by weight; and / or

[0016] Anti-sagging agent 2-7 parts by weight; and / or

[0017] Solvent 35-46 parts by weight.

[0018] In some embodiments of this disclosure, the thickness of the first paint film layer is 23-28 μm.

[0019] In some embodiments of this disclosure, the functional layer further includes a coating layer stacked on the side of the first coating layer facing away from the substrate, the coating layer comprising a silicon elemental layer and an oxide layer.

[0020] In some embodiments of this disclosure, the oxide layer includes an oxide layer of silicon and / or an oxide layer of niobium.

[0021] In some embodiments of this disclosure, when the coating layer is a silicon elemental layer, a silicon oxide layer, and a niobium oxide layer, the silicon oxide layer and the niobium oxide layer are alternately disposed in sequence.

[0022] In some embodiments of this disclosure, the thickness of the coating layer is 150-400 nm.

[0023] In some embodiments of this disclosure, the functional layer further includes a second paint film layer stacked on the side of the coating layer opposite to the first paint film layer, the second paint film layer being coated with a second coating material; the viscosity value of the second viscosity of the second coating material is within a second preset range.

[0024] In some embodiments of this disclosure, the second preset range is 23.3-26.7 mPa·s.

[0025] In some embodiments of this disclosure, the second coating comprises a second main component, which comprises the following raw materials in parts by weight:

[0026] 20-28 parts by weight of the first polyester resin;

[0027] Adhesion promoter 3-5 parts by weight;

[0028] Solvent 70-80 parts by weight;

[0029] The molecular weight of the first polyester resin is 10,000-30,000, and the glass transition temperature is 10-50℃.

[0030] In some embodiments of this disclosure, the thickness of the second paint film layer is 2-5 μm.

[0031] In some embodiments of this disclosure, the functional layer further includes a third paint film layer stacked on the side of the second paint film layer opposite to the coating layer, the third paint film layer being coated with a third paint coating; the viscosity value of the third paint coating is within a third preset range.

[0032] In some embodiments of this disclosure, the third preset range is 24.1-29.1 mPa·s.

[0033] In some embodiments of this disclosure, the third coating comprises a third main component, which includes the following raw materials in parts by weight:

[0034] 65-75 parts by weight of hydroxypropyl resin;

[0035] 5-10 parts by weight of cellulose acetate butyrate;

[0036] Solvent 11-29 parts by weight.

[0037] In some embodiments of this disclosure, the thickness of the third coating layer is 5-12 μm.

[0038] In some embodiments of this disclosure, the functional layer further includes a fourth paint film layer stacked on the side of the third paint film layer facing away from the second paint film layer, the fourth paint film layer being coated with a fourth coating material; the viscosity value of the fourth coating material is within a fourth preset range.

[0039] In some embodiments of this disclosure, the fourth preset range is 24.1-29.1 mPa·s.

[0040] In some embodiments of this disclosure, the fourth coating comprises a fourth main component, which includes the following raw materials in parts by weight:

[0041]

[0042] In some embodiments of this disclosure, the thickness of the fourth coating layer is 18-25 μm.

[0043] In some embodiments of this disclosure, the functional layer further includes a fifth paint film layer stacked between the substrate and the first paint film layer, the fifth paint film layer being coated with a fifth coating material; the viscosity value of the fifth coating material is within a fifth preset range.

[0044] In some embodiments of this disclosure, the fifth preset range is 24.1-29.1 mPa·s.

[0045] In some embodiments of this disclosure, the fifth coating comprises a fifth main component, which includes the following raw materials in parts by weight:

[0046]

[0047] In some embodiments of this disclosure, the thickness of the fifth coating layer is 5-10 μm.

[0048] In some embodiments of this disclosure, the functional layer further includes a sixth paint film layer stacked between the fifth paint film layer and the first paint film layer, the sixth paint film layer being coated with a sixth paint; the viscosity value of the sixth paint is within a sixth preset range.

[0049] In some embodiments of this disclosure, the sixth preset range is 24.1-29.1 mPa·s.

[0050] In some embodiments of this disclosure, the sixth coating comprises a sixth main component, which comprises the following raw materials in parts by weight:

[0051]

[0052] In some embodiments of this disclosure, the thickness of the sixth coating layer is 23-28 μm.

[0053] The functional layer further includes a first texture layer stacked on the side of the fourth paint film layer opposite to the third paint film layer, an anti-fingerprint layer stacked on the first texture layer on the side of the first texture layer opposite to the fourth paint film layer, and a second texture layer stacked on the side of the first paint film layer opposite to the substrate.

[0054] According to a second aspect of the present disclosure, a housing is provided, the housing being prepared from the substrate as described above, the housing comprising:

[0055] Main body;

[0056] A protrusion is disposed on the main body, the protrusion including an arc-shaped structure connected to the main body, the radius of the arc-shaped structure being 1.25-2.00 mm.

[0057] In some embodiments of this disclosure, the distance between the edge of the protrusion and the edge of the main body near the protrusion is 2.36-2.70 mm.

[0058] According to a third aspect of the present disclosure, an electronic device is provided, the electronic device including the housing as described above.

[0059] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects:

[0060] This disclosure controls the flowability of the first coating by controlling its first viscosity to be less than or equal to a first preset threshold, which helps to improve the uniformity of the first paint film thickness, reduce appearance defects such as frame marks, fabric marks, and oil accumulation, and protect the shell and improve its aesthetics.

[0061] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0062] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0063] Figure 1 This is a schematic diagram of the layer structure of a substrate for a housing, according to an exemplary embodiment;

[0064] Figure 2 This is a schematic diagram of the structure of the housing according to an exemplary embodiment;

[0065] Figure 3 This is a schematic flowchart illustrating a method for preparing a substrate for a housing according to an exemplary embodiment. Detailed Implementation

[0066] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0067] In recent years, fiberglass has been widely used in the back covers of electronic devices. Due to its advantages over glass, such as high strength, high impact resistance, and light weight, fiberglass is gradually replacing glass. In related technologies, fiberglass shells are formed by bonding a decorative layer to a fiberglass matrix. However, this type of bonded shell carries the risk of delamination and makes it difficult to create a 3D (three-dimensional) structure.

[0068] To address the aforementioned technical problems, this disclosure provides a substrate for a housing. The substrate includes a body and a functional layer disposed on at least one side of the body. The functional layer includes a first paint film layer, which is formed by coating with a first coating material. The viscosity value of the first coating material is within a first preset range. This disclosure, by coating the body with the first coating material to form the first paint film layer, can protect the housing and improve its aesthetics, reducing the risk of delamination that may occur due to the adhesion of decorative layers. Furthermore, by controlling the viscosity value of the first coating material within a first preset range, the flowability of the first coating material is controlled, which helps to improve the uniformity of the first paint film layer thickness and reduces appearance defects such as frame marks, fabric texture marks, and oil accumulation.

[0069] The specific embodiments described below are intended to help those skilled in the art understand this embodiment, but this embodiment is not limited to the specific embodiments described below.

[0070] like Figure 1 As shown, an exemplary embodiment of this disclosure provides a substrate for a housing. The substrate includes a body 1 and a functional layer 2 disposed on at least one side of the body 1. The functional layer 2 includes a first paint film layer 20, which is coated with a first paint coating. The viscosity value of the first paint coating is within a first preset range.

[0071] In this embodiment, the first coating is applied to the body 1 to form a first paint film layer 20, which can protect the shell and improve its aesthetics, reducing the risk of delamination that may occur due to the bonding of decorative layers.

[0072] To meet the demand for thinner and lighter electronic devices, the thickness of electronic devices is getting smaller and smaller. However, this limits the available space inside the electronic devices. In this case, in order to accommodate a large camera module, the camera part inevitably protrudes from the housing. Therefore, the housing can be designed with a "crater" structure to cover the edge of the assembled camera, so as to achieve the positioning and protection of the camera.

[0073] like Figure 2 As shown, the housing includes a main body 101 and a protrusion 201. The protrusion 201 is disposed on the main body 101 and includes an arc-shaped structure connected to the main body 101. The protrusion 201 is a crater structure, and it can be integrally formed with the main body 101 to create an arc-shaped edge and an overall structure resembling a volcano. The protrusion 201 can be located in any one of the upper left, upper right, or middle regions of the main body 101, or a combination thereof; the middle region is located between the upper left and upper right regions. The protrusion 201 may have a through-hole for accommodating a camera / flash module.

[0074] To enrich the appearance of the shell, a coating can be directly stacked on the body 1, followed by a printing process to achieve different visual effects. When the protrusion 201 is located in the middle area of ​​the main body 101, the pressure distribution in each area is uniform during printing, resulting in low printing difficulty and fewer appearance defects. However, when the protrusion 201 is located in the upper left or upper right corner of the main body 101, i.e., the protrusion 201 acts as a corner crater on the main body 101, the pressure distribution in each area is uneven during printing, which can easily lead to appearance problems such as frame marks, oil accumulation, and fabric texture marks. Therefore, to reduce appearance defects, the radius R of the arc structure of the protrusion 201 usually needs to be greater than 2 mm, and the distance H between the edge of the protrusion 201 and the edge of the main body 101 near the protrusion 201 also needs to be greater than 2.7 mm, which limits the diversity of shell designs.

[0075] In this embodiment, by controlling the viscosity value of the first viscosity of the first coating within a first preset range, the fluidity of the first coating is controlled, so that the first coating has low fluidity, preventing the first coating on the sidewall of the crater from flowing to the root of the crater, avoiding the problem of inconsistent paint film thickness around the crater, and also avoiding appearance defects such as frame marks caused by uneven printing pressure around the crater.

[0076] In an exemplary embodiment, the first preset range is 28.3-31.7 mPa·s.

[0077] Viscosity is a parameter that measures the resistance of a fluid to flow, reflecting its flow properties. The unit of viscosity, specifically millipascal-seconds (mPa·s), is millipascal-seconds (mPa·s), and it can be measured using a viscometer. A higher viscosity value indicates a longer flow time to a given volume, signifying lower fluidity. Conversely, a lower viscosity value indicates a shorter flow time to a given volume, signifying higher fluidity. However, excessively low fluidity (i.e., excessively high viscosity) can negatively impact the uniformity of paint mixing and film application, and may also lead to defects such as pinholes, bubbles, and orange peel after drying. Conversely, excessively high fluidity (i.e., excessively low viscosity) can affect the wettability of the paint and its adhesion to the substrate, and may cause sagging, resulting in uneven film thickness. Therefore, the viscosity needs to be controlled within a preset range to manage the fluidity of the first paint layer and ensure uniformity of the first film thickness.

[0078] In this embodiment, the first preset range is 28.3-31.7 mPa·s, that is, the viscosity value of the first viscosity is 28.3-31.7 mPa·s, in order to control the fluidity of the first coating, which is beneficial to improving the uniformity of the thickness of the first paint film layer 20 and reducing appearance defects such as frame marks, fabric texture marks, and oil accumulation on the substrate. Furthermore, controlling the first preset range within 9.7-12.3 s ensures good consistency in the thickness of the paint film around the crater. Exemplarily, the first preset range can be 28.3 mPa·s, 29.0 mPa·s, 29.4 mPa·s, 31.0 mPa·s, or 31.7 mPa·s. The first preset range can also be any viscosity value within the exemplary viscosity range; for example, the first preset range can also be any viscosity value between 29.0 and 31.0 mPa·s.

[0079] In an exemplary embodiment, the first coating includes a first main component, which comprises the following raw materials in parts by weight:

[0080] 20-50 parts by weight of multifunctional polyurethane acrylate;

[0081] 4-10 parts by weight of 2-functionality polyurethane acrylate;

[0082] 5-10 parts by weight of thermoplastic acrylic resin;

[0083] 0-4 parts by weight of multifunctional UV-curable monomer.

[0084] In this embodiment, by adjusting the formulation of the first coating, the viscosity of the first coating is adjusted so that the first coating has low fluidity, preventing the first coating on the sidewall of the crater from flowing to the root of the crater, thus avoiding the problem of inconsistent paint film thickness around the crater. At the same time, it also avoids appearance defects such as frame marks caused by uneven paint film thickness due to uneven printing pressure around the crater.

[0085] In this context, difunctional polyurethane acrylate refers to a compound containing two functional groups per molecule, while multifunctional polyurethane acrylate refers to a compound containing three or more functional groups per molecule. In the first coating of this embodiment, difunctional polyurethane acrylate provides good flexibility, while multifunctional polyurethane acrylate provides excellent adhesion and crosslinking density. The combination of difunctional and multifunctional polyurethane acrylates results in the first coating layer 20 exhibiting excellent adhesion, abrasion resistance, and other properties. The addition of thermoplastic acrylic resin facilitates subsequent printing processes. The addition of multifunctional ultraviolet radiation (UV) monomers gives the first coating good leveling and workability. For example, the multifunctional UV monomer can be a trifunctional UV monomer.

[0086] For example, in one embodiment, the first main component comprises the following raw materials in parts by weight:

[0087] 20 parts by weight of multifunctional polyurethane acrylate;

[0088] 4 parts by weight of 2-functionality polyurethane acrylate;

[0089] Five parts by weight of thermoplastic acrylic resin.

[0090] In another embodiment, the first main component comprises the following raw materials in parts by weight:

[0091] 45 parts by weight of multifunctional polyurethane acrylate;

[0092] 7 parts by weight of 2-functionality polyurethane acrylate;

[0093] 7 parts by weight of thermoplastic acrylic resin;

[0094] Two parts by weight of a multifunctional UV-curable monomer.

[0095] In another embodiment, the first main component comprises the following raw materials in parts by weight:

[0096]

[0097] In one exemplary embodiment, the multifunctional polyurethane acrylate includes trifunctional polyurethane acrylate, quadrifunctional polyurethane acrylate and nonfunctional polyurethane acrylate in a weight ratio of 0.67-3.60:0.67-3.00:1.

[0098] In this embodiment, the first paint film layer 20 can serve as a topcoat layer to provide a decorative effect. Furthermore, to enrich the visual appearance of the casing, textures can be imprinted on the first paint film layer 20. Therefore, the first paint film layer 20 also needs to have good imprinting properties. Specifically, trifunctional polyurethane acrylate provides good adhesion and imprinting properties, quadrifunctional polyurethane acrylate provides good adhesion, and nonfunctional polyurethane acrylate can increase the crosslinking density of the first paint film layer 20. Through the combination of trifunctional, quadrifunctional, and nonfunctional polyurethane acrylates, the first paint film layer 20 can achieve good bonding strength with the body 1. For example, the weight ratio of trifunctional polyurethane acrylate, tetrafunctional polyurethane acrylate, and nonfunctional polyurethane acrylate is 0.67:0.67:1, 1.00:1.25:1, 2.35:1.00:1, or 3.60:3.00:1. The weight ratio of trifunctional polyurethane acrylate, tetrafunctional polyurethane acrylate, and nonfunctional polyurethane acrylate can also be any ratio between the exemplary weight ratios; for example, the weight ratio of trifunctional polyurethane acrylate, tetrafunctional polyurethane acrylate, and nonfunctional polyurethane acrylate can also be any ratio between 1.00-2.35:1.00-1.25:1.

[0099] In one exemplary embodiment, the first main component further includes 1-8 parts by weight of a photoinitiator.

[0100] In this embodiment, the photoinitiator can induce the polymerization reaction of monomers and oligomers, resulting in the cured first paint film layer 20 having good hardness, adhesion, etc. Exemplarily, the amount of photoinitiator can be 1 part by weight, 2 parts by weight, 4 parts by weight, 6 parts by weight, or 8 parts by weight. The amount of photoinitiator can also be any amount between the exemplary amounts; for example, the amount of photoinitiator can be any amount between 2 and 6 parts by weight.

[0101] In an exemplary embodiment, the photoinitiator includes a first-band photoinitiator and a second-band photoinitiator in a weight ratio of 6.2-40.0:1, wherein the first-band photoinitiator is smaller than the second-band photoinitiator.

[0102] In this embodiment, the first-band photoinitiator can be a short-wavelength photoinitiator (absorption wavelength in the range of 250-350 nm), and the second-band photoinitiator can be a long-wavelength photoinitiator (absorption wavelength in the range of 350-400 nm). The combination of the short-wavelength and long-wavelength photoinitiators can balance the curing speed and curing depth, thereby improving the processability of the first coating. Exemplarily, the weight ratio of the first-band photoinitiator to the second-band photoinitiator can be 6.2:1, 15.8:1, 27.7:1, 33.3:1, or 40.0:1. The weight ratio of the first-band photoinitiator to the second-band photoinitiator can also be any ratio between the exemplary weight ratios; for example, the weight ratio of the first-band photoinitiator to the second-band photoinitiator can also be any ratio between 15.8 and 33.3:1. The first-band photoinitiator can be, for example, one of photoinitiator 184, photoinitiator 1173, photoinitiator BDK, photoinitiator MBF, and photoinitiator 2959, or a combination of several of them. For example, the first-band photoinitiator can be a combination of photoinitiator 184 and photoinitiator 1173 in a weight ratio of 1-30:1. The second-band photoinitiator can be, for example, one or more of photoinitiator TPO and photoinitiator 819.

[0103] In one exemplary embodiment, the first main component further includes:

[0104] Leveling agent 0.1-0.5 parts by weight; and / or

[0105] Anti-sagging agent 2-7 parts by weight; and / or

[0106] Solvent 35-46 parts by weight.

[0107] In this embodiment, the first main component further includes one or more of a leveling agent, an anti-sagging agent, and a solvent. The leveling agent can improve the leveling properties of the first coating, improve the uniformity of the thickness of the first paint film layer 20, reduce surface defects such as pinholes and craters in the first paint film layer 20, and improve the aesthetics of the first paint film layer 20. Exemplarily, the amount of leveling agent used is 0.1 parts by weight, 0.2 parts by weight, 0.4 parts by weight, or 0.5 parts by weight. The amount of leveling agent used can also be any amount between the exemplary amounts; for example, the amount of leveling agent can also be any amount between 0.2 and 0.4 parts by weight. The leveling agent can be, for example, a polyether-modified polysiloxane leveling agent.

[0108] The anti-sagging agent can increase the initial viscosity of the first coating, thereby increasing the anti-flow ability of the first coating on the crater sidewall and improving the uniformity of the first coating thickness. Exemplarily, the anti-sagging agent can be 2 parts by weight, 3 parts by weight, 5 parts by weight, or 7 parts by weight. The amount of anti-sagging agent used can also be any amount between these exemplary amounts; for example, the amount of anti-sagging agent can be any amount between 3 and 5 parts by weight. The anti-sagging agent can be, for example, a modified urea anti-sagging agent.

[0109] The addition of solvents can adjust the initial viscosity, flowability, and drying speed of the first coating. Solvents can be, for example, one or a mixture of several ester solvents, alcohol solvents, ether solvents, benzene solvents, and ketone solvents. Ester solvents can be, for example, one or more of ethyl acetate, butyl acetate, and ethylene glycol ethyl ether acetate; alcohol solvents can be, for example, one or more of methanol and ethanol; ether solvents can be, for example, one or more of ethylene glycol ethyl ether, ethylene glycol butyl ether, and propylene glycol methyl ether; benzene solvents can be, for example, one or more of toluene; and ketone solvents can be, for example, one or more of acetone and butanone.

[0110] The first coating may further include a diluent, wherein the first main component and the diluent are mixed at a weight ratio of 100:0-30 to adjust the first viscosity, flowability, and drying speed of the first coating. The diluent may be the same as or different from the solvent, as long as it meets the purpose of this disclosure.

[0111] In an exemplary embodiment, the thickness of the first paint film layer 20 is 23-28 μm.

[0112] In this embodiment, the thickness of the first paint film layer 20 can be controlled between 23-28 μm. If the thickness is too thick, appearance defects such as frame marks and oil accumulation are likely to occur; if the thickness is too thin, it will be difficult to cover the fabric texture marks formed by the integral molding of the volcano crater. For example, the thickness of the first paint film layer 20 is 23 μm, 24 μm, 26 μm, 27 μm, or 28 μm. The thickness of the first paint film layer 20 can also be any thickness between the exemplary thickness values, for example, the thickness of the first paint film layer 20 can be any thickness value between 24-27 μm.

[0113] In one exemplary embodiment, the body 1 includes a multilayer glass fiber reinforced resin composite board.

[0114] In this embodiment, the body 1 comprises a multilayer glass fiber reinforced resin composite board, for example, 2-8 layers. The same type of glass fiber reinforced resin composite board can be used for lamination, or different types can be used. When a composite board with a higher glass fiber content is used, the texture of the laminated body 1 will be aggravated. Therefore, in this embodiment, the body 1 can be made by laminating three layers of 2116 type glass fiber reinforced resin composite board and two layers of 1080 type glass fiber reinforced resin composite board.

[0115] In an exemplary embodiment, the functional layer 2 further includes a coating layer 21 stacked on the side of the first coating layer 20 away from the substrate, the coating layer 21 comprising a silicon elemental layer and an oxide layer.

[0116] In this embodiment, by setting the coating layer 21, the appearance and visual effect of the substrate can be improved, and the substrate can be protected. The water droplet angle of the coating layer 21 after ion source cleaning is 15-35°. The small water droplet angle of the coating layer 21 gives it good hydrophilicity and wettability, which is beneficial for the uniform distribution of subsequent coatings on its surface. Furthermore, the low water droplet angle also helps to reduce light reflection and heat dissipation, thereby improving the light transmittance of the coating layer 21.

[0117] In one exemplary embodiment, the oxide layer includes an oxide layer of silicon and / or an oxide layer of niobium.

[0118] In this embodiment, the oxide layer of silicon can be a silicon dioxide (SiO2) layer, and the oxide layer of niobium can be niobium pentoxide (Nb2O5). Silicon dioxide has the characteristics of high transmittance and low refractive index, while niobium pentoxide has the characteristics of high refractive index and high transparency. By combining silicon dioxide and niobium pentoxide, the appearance of the substrate can be enriched.

[0119] In an exemplary embodiment, when the coating layer 21 is a silicon elemental layer, a silicon oxide layer, and a niobium oxide layer, the silicon oxide layer and the niobium oxide layer are alternately disposed in sequence.

[0120] In this embodiment, the coating layer 21 is based on a single layer of silicon, and then silicon dioxide and niobium pentoxide are used for cross-layering. The number of layers can be set as needed, and can be 3-8 layers; for example, the coating layer 21 is Si / SiO2 / Nb2O5 / SiO2 / Nb2O5 / SiO2 / Nb2O5.

[0121] In an exemplary embodiment, the thickness of the coating layer 21 is 150-400 nm.

[0122] In this embodiment, the visual appearance of the substrate can be adjusted by controlling the thickness of the coating layer 21. For example, the thickness of the coating layer 21 can be 150nm, 180nm, 230nm, 280nm, 350nm, or 400nm. The thickness of the coating layer 21 can also be any thickness between the exemplary values; for example, the thickness of the coating layer 21 can be any thickness value between 180-280nm.

[0123] In an exemplary embodiment, the functional layer 2 further includes a second paint film layer 22 stacked on the side of the coating layer 21 opposite to the first paint film layer 20, the second paint film layer 22 being coated with a second paint; the viscosity value of the second viscosity of the second paint is within a second preset range.

[0124] In this embodiment, by setting the second paint film layer 22, the impact toughness of the shell can be improved, solving the problems of microcracks in the shell during whole-machine roller and directional drop. The shell prepared using the substrate of this embodiment shows no cracks at a height of 80-100cm during a 32g drop ball test; after 100 whole-machine roller rotations and a directional drop of 1m, the number of shells with microcracks is ≤1 / 40 (i.e., out of 40 shells tested, the number of shells with microcracks is 0 or 1). The second paint film layer 22, acting as a primer, improves the smoothness of the coating layer 21 and enhances the adhesion between the intermediate paint layer and the coating layer 21.

[0125] In one exemplary embodiment, the second preset range is 23.3-26.7 mPa·s.

[0126] In this embodiment, the second preset range is 23.3-26.7 mPa·s, meaning the viscosity value of the second viscosity is 23.3-26.7 mPa·s. This controls the flowability of the second coating, which helps improve the uniformity of the thickness of the second paint film layer 22 and further reduces appearance defects such as frame marks, fabric texture marks, and oil accumulation on the substrate. Furthermore, controlling the second preset range within 23.3-26.7 mPa·s allows the second paint film layer 22 to have better impact resistance. Exemplarily, the second preset range can be 23.3 mPa·s, 23.9 mPa·s, 24.5 mPa·s, 25.9 mPa·s, or 26.7 mPa·s. The second preset range can also be any viscosity value within the exemplary viscosity range; for example, the second viscosity can be any viscosity value between 23.9 and 25.9 mPa·s.

[0127] In one exemplary embodiment, the second coating includes a second main component, which comprises the following raw materials in parts by weight:

[0128] 20-28 parts by weight of the first polyester resin;

[0129] Adhesion promoter 3-5 parts by weight;

[0130] Solvent 70-80 parts by weight;

[0131] The molecular weight of the first polyester resin is 10,000-30,000, and the glass transition temperature is 10-50℃.

[0132] In this embodiment, by adjusting the formulation of the second coating, and by using a softer polyester resin with a molecular weight of 10,000-30,000 and a glass transition temperature (Tg) of 10-50°C as the first polyester resin, the second coating layer 22 can have better impact resistance and toughness.

[0133] The adhesion promoter can be one or more of phosphate ester adhesion promoters and silane coupling agents. Phosphate ester adhesion promoters can be one or more of polyphosphate ester adhesion promoters and epoxy phosphate ester adhesion promoters. Silane coupling agents can be γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), etc. The type of solvent is not limited, as long as it achieves the purpose of this disclosure; it can also be the same as the solvent in the above embodiments, and will not be described again here.

[0134] The second coating may further include a curing agent and a diluent. The second main component is mixed with the curing agent and diluent in a weight ratio of 100:2.5:150-250 to adjust the viscosity, flowability, and drying speed of the second coating. The curing agent may be, for example, an isocyanate, and the diluent may be the same as or different from the solvent, as long as it meets the purpose of this disclosure. The specific selection of solvents and diluents in each coating in this disclosure can be the same as that in the first coating, and will not be repeated here.

[0135] For example, in one embodiment, the second main component comprises the following raw materials in parts by weight:

[0136] 20 parts by weight of the first polyester resin;

[0137] Adhesion promoter 3 parts by weight;

[0138] Solvent 70 parts by weight.

[0139] In another embodiment, the second main component comprises the following raw materials in parts by weight:

[0140] 24 parts by weight of the first polyester resin;

[0141] 4 parts by weight of adhesion promoter;

[0142] Solvent 75 parts by weight.

[0143] In another embodiment, the second main component comprises the following raw materials in parts by weight:

[0144] 28 parts by weight of the first polyester resin;

[0145] 5 parts by weight of adhesion promoter;

[0146] Solvent, 80 parts by weight.

[0147] In an exemplary embodiment, the thickness of the second paint film layer 22 is 2-5 μm.

[0148] In this embodiment, the thickness of the second paint film layer 22 is 2-5 μm, which allows the second paint film layer 22 to maintain better mechanical properties. For example, the thickness of the second paint film layer 22 can be 2 μm, 3 μm, 4 μm, or 5 μm.

[0149] In an exemplary embodiment, the functional layer 2 further includes a third paint film layer 23 stacked on the side of the second paint film layer 22 opposite to the coating layer 21, the third paint film layer 23 being coated with a third paint; the viscosity value of the third paint is within a third preset range.

[0150] In this embodiment, by providing a third paint film layer 23, the visual appearance of the casing can be further enriched. As a middle paint layer, the third paint film layer 23 can increase the total thickness of the functional layer 2 and further enhance the adhesion between the primer layer and the topcoat layer, thereby improving the overall performance of the functional layer 2.

[0151] In one exemplary embodiment, the third preset range is 24.1-29.1 mPa·s.

[0152] In this embodiment, by controlling the third preset range within 24.1-29.1 mPa·s, the third coating can achieve better coating uniformity. Exemplarily, the third preset range is 24.1 mPa·s, 25.0 mPa·s, 26.0 mPa·s, 26.5 mPa·s, 27.7 mPa·s, 28.3 mPa·s, and 29.1 mPa·s. The third preset range can also be any viscosity value within the exemplary range; for example, it can be any viscosity value between 26.0 and 27.7 mPa·s.

[0153] In one exemplary embodiment, the third coating includes a third main component, which comprises the following raw materials in parts by weight:

[0154] 65-75 parts by weight of hydroxypropyl resin;

[0155] 5-10 parts by weight of cellulose acetate butyrate;

[0156] Solvent 11-29 parts by weight.

[0157] In this embodiment, hydroxypropyl resin refers to an acrylic resin containing hydroxyl functional groups, also known as hydroxyl acrylic resin, which has good bonding strength and chemical resistance. Cellulose acetate butyrate (CAB) can improve the flexibility and leveling properties of the third coating. Through the combination of hydroxypropyl resin and cellulose acetate butyrate, the third coating layer 23 can have good bonding strength and impact toughness.

[0158] The third coating also includes a curing agent and a diluent. The third main component, curing agent and diluent are mixed in a weight ratio of 100:5:150-250 to adjust the third viscosity, flowability and drying speed of the third coating.

[0159] For example, in one embodiment, the third main component comprises the following raw materials in parts by weight:

[0160] 65 parts by weight of hydroxypropyl resin;

[0161] 5 parts by weight of cellulose acetate butyrate;

[0162] Solvent 11 parts by weight.

[0163] In another embodiment, the third main component comprises the following raw materials in parts by weight:

[0164] 70 parts by weight of hydroxypropyl resin;

[0165] 8 parts by weight of cellulose acetate butyrate;

[0166] Solvent 20 parts by weight.

[0167] In another embodiment, the third main component comprises the following raw materials in parts by weight:

[0168] 75 parts by weight of hydroxypropyl resin;

[0169] 10 parts by weight of cellulose acetate butyrate;

[0170] Solvent: 29 parts by weight.

[0171] In an exemplary embodiment, the thickness of the third paint film layer 23 is 5-12 μm.

[0172] In this embodiment, by controlling the thickness of the third paint film layer 23 to be between 5 and 12 μm, the third paint film layer 23 can maintain better mechanical properties. Exemplarily, the thickness of the third paint film layer 23 can be 5 μm, 7 μm, 10 μm, or 12 μm. The thickness value of the third paint film layer 23 can also be any thickness value between the exemplary values; for example, the thickness value of the third paint film layer 23 can also be any thickness value between 7 and 10 μm.

[0173] In an exemplary embodiment, the functional layer 2 further includes a fourth paint film layer 24 stacked on the side of the third paint film layer 23 facing away from the second paint film layer 22, the fourth paint film layer 24 being coated with a fourth paint; the viscosity value of the fourth viscosity of the fourth paint is within a fourth preset range.

[0174] In this embodiment, by setting a fourth paint film layer 24, the appearance visual effect of the shell can be further enriched, and the body 1 can be protected.

[0175] In one exemplary embodiment, the fourth preset range is 24.1-29.1 mPa·s.

[0176] In this embodiment, by controlling the fourth preset range within 24.1-29.1 mPa·s, the fourth coating can achieve better coating uniformity. Exemplarily, the fourth preset range is 24.1 mPa·s, 25.0 mPa·s, 26.0 mPa·s, 26.5 mPa·s, 27.7 mPa·s, 28.3 mPa·s, and 29.1 mPa·s. The fourth preset range can also be any viscosity value within the exemplary viscosity range; for example, the fourth preset range can also be any viscosity value between 26.0 and 27.7 mPa·s.

[0177] In one exemplary embodiment, the fourth coating includes a fourth main component, which comprises the following raw materials in parts by weight:

[0178]

[0179] In this embodiment, the fourth paint film layer 24 serves as a topcoat layer, enhancing the aesthetics of the shell. Furthermore, to further enrich the visual appearance of the shell, a double-layer imprinting method can be employed, i.e., imprinting textures onto the fourth paint film layer 24. Therefore, the fourth paint film layer 24 also needs to possess good imprinting properties. Thus, in the fourth coating, trifunctional polyurethane acrylate provides good adhesion and imprinting properties, quadrifunctional polyurethane acrylate provides good adhesion, and hexafunctional and nonfunctional polyurethane acrylates can increase the crosslinking density of the fourth paint film layer 24. The combination of trifunctional, quadrifunctional, hexafunctional, and nonfunctional polyurethane acrylates ensures good bonding strength between the first paint film layer 20 and the body 1.

[0180] The trifunctional polyurethane acrylate can be compounded using a weight ratio of first-trifunctional polyurethane acrylate, second-trifunctional polyurethane acrylate, and third-trifunctional polyurethane acrylate in the range of 1:1-5:3-22. The first-trifunctional polyurethane acrylate provides good adhesion, the second-trifunctional polyurethane acrylate provides good adhesion and printing effect, and the third-trifunctional polyurethane acrylate is a soft resin with a low glass transition temperature (e.g., 20-60℃), providing good flexibility.

[0181] The leveling agent can be a polyether-modified polysiloxane leveling agent, which can improve the leveling properties of the fourth coating, thereby improving the uniformity and aesthetics of the fourth film layer 24 thickness. The photoinitiator can improve the curing efficiency and film-forming properties of the film layer. The type of photoinitiator in this embodiment can be the same as in the above embodiments, and will not be repeated here.

[0182] The fourth coating also includes a curing agent and a diluent. The fourth main component and the diluent are mixed at a weight ratio of 100:20-60 to adjust the fourth coating's viscosity, flowability, and drying speed.

[0183] For example, in one embodiment, the fourth main component comprises the following raw materials in parts by weight:

[0184]

[0185] In another embodiment, the fourth main component comprises the following raw materials in parts by weight:

[0186]

[0187] In another embodiment, the fourth main component comprises the following raw materials in parts by weight:

[0188]

[0189]

[0190] In an exemplary embodiment, the thickness of the fourth paint film layer 24 is 18-25 μm.

[0191] In this embodiment, the thickness of the fourth paint film layer 24 can be 18μm, 20μm, 22μm, or 25μm. The thickness of the fourth paint film layer 24 can also be any thickness between the exemplary thickness values; for example, the thickness of the fourth paint film layer 24 can be any thickness value between 20 and 22μm.

[0192] In an exemplary embodiment, the functional layer 2 further includes a fifth paint film layer 25 stacked between the substrate and the first paint film layer 20, the fifth paint film layer 25 being coated with a fifth paint; the viscosity value of the fifth paint is within a fifth preset range.

[0193] In this embodiment, the fifth paint film layer 25 serves as a primer, which can seal the pores, micro-cracks, and unevenness of the body 1, thereby improving the adhesion of other paint film layers to the body 1.

[0194] In one exemplary embodiment, the fifth preset range is 24.1-29.1 mPa·s.

[0195] In this embodiment, by controlling the fifth preset range within 24.1-29.1 mPa·s, the fifth coating can achieve better coating uniformity. Exemplarily, the fifth preset range is 24.1 mPa·s, 25.0 mPa·s, 26.0 mPa·s, 26.5 mPa·s, 27.7 mPa·s, 28.3 mPa·s, and 29.1 mPa·s. The fifth preset range can also be any viscosity value within the exemplary viscosity range; for example, the fifth preset range can also be any viscosity value between 26.0 and 27.7 mPa·s.

[0196] In one exemplary embodiment, the fifth coating includes a fifth main component, which comprises the following raw materials in parts by weight:

[0197]

[0198] In this embodiment, the visual appearance of the substrate is adjusted by varying the amounts of each component. The second polyester resin can be a polyester resin with a molecular weight of 10,000-30,000. The first filler can improve the strength of the fifth paint film layer 25; for example, the first filler can be talc, matting powder, etc. To provide better masking for the substrate 1, color paste can also be added to the first filler. For example, to obtain a gray fifth paint film layer 25, the first filler may include 1-6 parts by weight of talc, 1-3 parts by weight of matting powder, 2-7 parts by weight of black paste, and 20-30 parts by weight of white paste. The specific selection of the adhesion promoter can be the same as in the above embodiment and will not be repeated here. The drying agent can be a metal oxide or its salt drying agent to improve the drying speed of the fifth paint film layer 25.

[0199] The fifth coating also includes a curing agent and a diluent. The fifth main component, curing agent and diluent are mixed in a weight ratio of 100:5:150-250 to adjust the fifth coating's viscosity, flowability and drying speed.

[0200] In one embodiment, for example, the fifth main component comprises the following parts by weight of raw materials:

[0201]

[0202] In another embodiment, the fifth main component comprises the following raw materials in parts by weight:

[0203]

[0204] In another embodiment, the fifth main component comprises the following raw materials in parts by weight:

[0205]

[0206] In an exemplary embodiment, the thickness of the fifth paint film layer 25 is 5-10 μm.

[0207] In this embodiment, by controlling the thickness of the fifth paint film layer 25 to be between 5 and 10 μm, the fifth paint film layer 25 can maintain better mechanical properties. Exemplarily, the thickness of the fifth paint film layer 25 can be 5 μm, 7 μm, 9 μm, or 10 μm. The thickness value of the fifth paint film layer 25 can also be any thickness value between the exemplary values; for example, the thickness value of the fifth paint film layer 25 can also be any thickness value between 7 and 9 μm.

[0208] In an exemplary embodiment, the functional layer 2 further includes a sixth paint film layer 26 stacked between the fifth paint film layer 25 and the first paint film layer 20, the sixth paint film layer 26 being coated with a sixth paint; the viscosity value of the sixth viscosity of the sixth paint is within a sixth preset range.

[0209] In this embodiment, the sixth paint film layer 26 can serve as a mid-layer paint layer, which can increase the total thickness of the functional layer 2 and further enhance the adhesion between the primer layer and the topcoat layer, thereby improving the overall performance of the functional layer 2.

[0210] In one exemplary embodiment, the sixth preset range is 24.1-29.1 mPa·s.

[0211] In this embodiment, by controlling the sixth preset range within 24.1-29.1 mPa·s, the sixth coating can achieve better coating uniformity. Exemplarily, the sixth preset range is 24.1 mPa·s, 25.0 mPa·s, 26.0 mPa·s, 26.5 mPa·s, 27.7 mPa·s, 28.3 mPa·s, and 29.1 mPa·s. The sixth preset range can also be any viscosity value within the exemplary range; for example, it can be any viscosity value between 26.0 and 27.7 mPa·s.

[0212] In an exemplary embodiment, the sixth coating includes a sixth main component, which comprises the following raw materials in parts by weight:

[0213]

[0214] In an exemplary embodiment, the sixth coating includes a sixth main component, which comprises the following raw materials in parts by weight:

[0215]

[0216] In this embodiment, the visual appearance of the substrate is adjusted by modifying the amount of each component. The second filler includes a color paste, which provides better masking for the substrate 1. For example, the second filler may include 0.1-1 parts by weight of blue paste, 0.5-1.5 parts by weight of red paste, 1-5 parts by weight of black paste, and 20-30 parts by weight of white paste. An anti-settling agent improves the rheological properties of the sixth coating, prevents the settling of the second filler, and helps maintain the uniformity and stability of the sixth coating. For example, a modified urea anti-settling agent can be selected. The drier can be a metal oxide or its salt drier to increase the drying speed of the sixth paint film layer 26.

[0217] The sixth coating also includes a curing agent and a diluent. The sixth main component, curing agent and diluent are mixed in a weight ratio of 100:20:60-120 to adjust the sixth viscosity, flowability and drying speed of the sixth coating.

[0218] In one embodiment, for example, the sixth main component comprises the following raw materials in parts by weight:

[0219]

[0220] In another embodiment, the sixth main component comprises the following raw materials in parts by weight:

[0221]

[0222] In another embodiment, the sixth main component comprises the following raw materials in parts by weight:

[0223]

[0224] In an exemplary embodiment, the thickness of the sixth paint film layer 26 is 23-28 μm.

[0225] In this embodiment, by controlling the thickness of the sixth paint film layer 26 to be between 23 and 28 μm, the sixth paint film layer 26 can maintain better mechanical properties. Exemplarily, the thickness of the sixth paint film layer 26 can be 23 μm, 25 μm, 27 μm, or 28 μm. The thickness value of the sixth paint film layer 26 can also be any thickness value between the exemplary values; for example, the thickness value of the sixth paint film layer 26 can also be any thickness value between 25 and 27 μm.

[0226] In an exemplary embodiment, the functional layer 2 further includes a first texture layer 27 stacked on the side of the fourth paint film layer 24 away from the third paint film layer 23, an anti-fingerprint layer 29 stacked on the first texture layer 27 away from the fourth paint film layer 24, and a second texture layer 28 stacked on the side of the first paint film layer 20 away from the substrate.

[0227] In this embodiment, by setting the first texture layer 27 and the second texture layer 28, the visual appearance of the shell can be further enriched. By setting the anti-fingerprint layer 29, the surface cleaning effect of the shell can be improved. After setting the anti-fingerprint layer 29, the water droplet angle on its surface can reach more than 110°.

[0228] like Figure 2 As shown, an exemplary embodiment of this disclosure provides a housing, the housing being fabricated from the substrate described above, the housing comprising:

[0229] Main body 101;

[0230] The protrusion 201 is disposed on the main body 101. The protrusion 201 includes an arc-shaped structure connected to the main body 101, and the radius of the arc-shaped structure is 1.25-2.00mm.

[0231] In this embodiment, by adjusting the formulation of each coating, the appearance defects of the protrusion 201 are significantly reduced after being decorated by the functional layer 2, and the radius R can be 1.25-2.00 mm, further enriching the diverse design of the shell's appearance. Exemplarily, the radius is 1.25 mm, 1.40 mm, 1.51 mm, 1.78 mm, or 2.00 mm. The radius can also be any value between the exemplary radius values; for example, the radius can be any value between 1.40 and 1.78 mm.

[0232] In an exemplary embodiment, the distance between the edge of the protrusion 201 and the edge of the main body 101 near the protrusion 201 is 2.36-2.70 mm.

[0233] In this embodiment, after the protrusion 201 is decorated by the functional layer 2, its appearance defects are significantly reduced. The distance H between the edge of the protrusion 201 and the edge of the main body 101 near the protrusion 201 can be 2.36-2.70 mm, further enriching the diverse design of the shell's appearance. Exemplarily, the distance can be 2.36 mm, 2.43 mm, 2.50 mm, 2.61 mm, or 2.70 mm. The distance can also be any value between the exemplary distance values; for example, the distance can be any value between 2.43 and 2.61 mm.

[0234] This disclosure resolves appearance issues such as frame marks, oil accumulation, and fabric texture marks caused by reducing the radius of curvature R and edge distance H in the functional layer 2 by adjusting the formulation of each coating. This allows the radius of curvature R to be 1.25-2.00 mm and the edge distance to be 2.36-2.70 mm. Furthermore, when printing on the body 1, it avoids appearance defects such as frame marks caused by uneven printing pressure around the protrusion 201, thus removing restrictions on the placement of the protrusion 201 and further enriching the diverse design possibilities of the shell. In addition, by adjusting the formulation of each coating, different stacking requirements of the body 1 can be met, and it can also adapt to the process requirements of integral molding of the body 101 and the protrusion 201.

[0235] like Figure 3 The present disclosure provides an exemplary embodiment of a method for preparing a substrate for a housing, comprising:

[0236] S110, Provide the main body.

[0237] In step S110, providing the body includes: holding a multi-layer glass fiber reinforced resin composite board at a molding temperature of 170-200℃ and a molding pressure of 160-240 bar for 400-500 seconds. Using these conditions optimizes the fabric texture imprint produced by the integrated molding of the crater and flash hole, resulting in a shallower imprint and improved visual appearance of the casing.

[0238] For example, in one embodiment, the molding temperature is 170°C, the molding pressure is 160 bar, and the molding time is 500 s.

[0239] In another embodiment, the molding temperature is 185°C, the molding pressure is 200 bar, and the molding time is 480 s.

[0240] In another embodiment, the molding temperature is 200°C, the molding pressure is 240 bar, and the molding time is 400 s.

[0241] S120. Apply the first coating to the surface of the substrate and cure it under the first preset conditions to form a first paint film layer, thereby obtaining the substrate; wherein, the functional layer includes the first paint film layer.

[0242] In step S120, the first preset condition can be: leveling at room temperature (20-25℃) for 3-6 minutes, and then drying at 50-60℃ for 5-8 minutes.

[0243] In one embodiment, for example, the first preset conditions include: leveling at 20°C for 6 minutes and then drying at 50°C for 8 minutes.

[0244] In another embodiment, the first preset conditions include: leveling at 22°C for 5 minutes, and then drying at 55°C for 6 minutes.

[0245] In another embodiment, the first preset conditions include: leveling at 25°C for 3 minutes, and then drying at 60°C for 5 minutes.

[0246] In one exemplary embodiment, the preparation method further includes:

[0247] An optical coating process is performed on the first paint film layer 20 to form a coating layer 21.

[0248] In this embodiment, the photoluminescence coating process can be performed by methods such as thermal evaporation, electron beam evaporation, and sputtering to deposit the coating layer 21.

[0249] In one exemplary embodiment, the preparation method further includes:

[0250] The second coating is applied to the surface of the coating layer 21 and cured under the second preset conditions to form the second paint film layer 22.

[0251] In this embodiment, the second preset conditions include: leveling at a temperature of 20-25°C for 3-6 minutes, and then drying at a temperature of 65-75°C for 10-18 minutes.

[0252] In one embodiment, for example, the second preset conditions include: leveling at 20°C for 6 minutes and then drying at 65°C for 18 minutes.

[0253] In another embodiment, the second preset conditions include: leveling at 22°C for 5 minutes, and then drying at 70°C for 12 minutes.

[0254] In another embodiment, the second preset conditions include: leveling at 25°C for 3 minutes, and then drying at 75°C for 10 minutes.

[0255] In one exemplary embodiment, the preparation method further includes:

[0256] The third coating is applied to the surface of the second paint film layer 22 and cured under the third preset conditions to form the third paint film layer 23.

[0257] In this embodiment, the third preset conditions include: leveling at a temperature of 20-25°C for 3-6 minutes, and then drying at a temperature of 65-75°C for 10-18 minutes.

[0258] In one embodiment, for example, the third preset conditions include: leveling at 20°C for 6 minutes and then drying at 65°C for 18 minutes.

[0259] In another embodiment, the third preset conditions include: leveling at 22°C for 5 minutes, and then drying at 70°C for 12 minutes.

[0260] In another embodiment, the third preset conditions include: leveling at 25°C for 3 minutes, and then drying at 75°C for 10 minutes.

[0261] In one exemplary embodiment, the preparation method further includes:

[0262] The fourth coating is applied to the surface of the third paint film layer 23 and cured under the fourth preset conditions to form the fourth paint film layer 24.

[0263] In this embodiment, the fourth preset condition can be: leveling at a temperature of 20-25°C for 3-6 minutes, and then drying at a temperature of 50-60°C for 5-8 minutes.

[0264] In one embodiment, for example, the fourth preset condition includes: leveling at 20°C for 6 minutes and then drying at 50°C for 8 minutes.

[0265] In another embodiment, the fourth preset condition includes: leveling at 22°C for 5 minutes, and then drying at 55°C for 6 minutes.

[0266] In another embodiment, the fourth preset condition includes: leveling at 25°C for 3 minutes, and then drying at 60°C for 5 minutes.

[0267] In one exemplary embodiment, before applying the first coating to the surface of the body 1, the preparation method further includes:

[0268] The fifth coating is applied to the surface of the main body 1 and cured under the fifth preset conditions to form the fifth paint film layer 25.

[0269] In this embodiment, the fifth preset condition includes: leveling at a temperature of 20-25°C for 3-6 minutes, and then drying at a temperature of 65-75°C for 10-18 minutes.

[0270] In one embodiment, for example, the fifth preset condition includes: leveling at 20°C for 6 minutes and then drying at 65°C for 18 minutes.

[0271] In another embodiment, the fifth preset condition includes: leveling at 22°C for 5 minutes, and then drying at 70°C for 12 minutes.

[0272] In another embodiment, the fifth preset condition includes: leveling at 25°C for 3 minutes, and then drying at 75°C for 10 minutes.

[0273] In an exemplary embodiment, the preparation method includes: coating a sixth layer onto the surface of a fifth paint film layer 25 and curing it under a sixth preset condition to form a sixth paint film layer 26.

[0274] In this embodiment, the sixth preset condition includes: leveling at a temperature of 20-25°C for 3-6 minutes, and then drying at a temperature of 65-75°C for 10-18 minutes.

[0275] In one embodiment, for example, the sixth preset condition includes: leveling at 20°C for 6 minutes and then drying at 65°C for 18 minutes.

[0276] In another embodiment, the sixth preset condition includes: leveling at 22°C for 5 minutes, and then drying at 70°C for 12 minutes.

[0277] In another embodiment, the sixth preset condition includes: leveling at 25°C for 3 minutes, and then drying at 75°C for 10 minutes.

[0278] In one exemplary embodiment, the preparation method further includes:

[0279] Under the seventh preset condition, an imprinting process is performed on the fourth paint film layer 24 to form the first texture layer 27.

[0280] In this embodiment, a silicone head with a hardness of 65-75A can be used for printing. The size and structural dimensions of the silicone head are designed according to a 1:1 scale, either conforming to the shape or with interference fit and a 0.05mm indentation. The printing equipment settings are as follows:

[0281] The master cylinder descent pressure is 95-105; the master cylinder descent speed is 95-105; the master cylinder ascent pressure is 95-105; the master cylinder ascent speed is 55-65; the master cylinder slow speed pressure is 145-155; the master cylinder slow speed is 45-55.

[0282] The mold core descending pressure is 95-105; the mold core descending speed is 55-65; the mold core rising pressure is 65-75; the mold core rising speed is 55-65; the mold core slow speed pressure is 60-70; the mold core slow speed is 5-10.

[0283] After the texture is imprinted, it can be cured twice; the first curing uses an LED light source with an energy of 250-450 mJ / cm². 2 UV intensity is 70-200mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 800-1000 mJ / cm². 2 Strength is 100-150 mW / cm 2 .

[0284] For example, in one embodiment, the printing equipment is set with the following parameters: main cylinder descent pressure of 95; main cylinder descent speed of 95; main cylinder ascent pressure of 95; main cylinder ascent speed of 55; main cylinder slow speed pressure of 145; and main cylinder slow speed of 45.

[0285] The mold core descending pressure is 95; the mold core descending speed is 55; the mold core rising pressure is 65; the mold core rising speed is 55; the mold core slow speed pressure is 60; the mold core slow speed is 5.

[0286] In another embodiment, the printing equipment is configured with the following parameters: main cylinder descent pressure of 100; main cylinder descent speed of 100; main cylinder ascent pressure of 100; main cylinder ascent speed of 60; main cylinder slow speed pressure of 150; and main cylinder slow speed of 50.

[0287] The mold core descending pressure is 100; the mold core descending speed is 60; the mold core rising pressure is 70; the mold core rising speed is 60; the mold core slow speed pressure is 65; the mold core slow speed is 8.

[0288] In another embodiment, the printing equipment is configured with the following parameters: main cylinder descent pressure 105; main cylinder descent speed 105; main cylinder ascent pressure 105; main cylinder ascent speed 65; main cylinder slow speed pressure 155; main cylinder slow speed 55.

[0289] The mold core descending pressure is 105; the mold core descending speed is 65; the mold core rising pressure is 75; the mold core rising speed is 65; the mold core slow speed pressure is 70; the mold core slow speed is 10.

[0290] In one embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 250 mJ / cm². 2 UV intensity is 200mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 800 mJ / cm². 2 Strength is 150mW / cm 2 .

[0291] In another embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 350 mJ / cm². 2 UV intensity is 140mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 900 mJ / cm². 2 Strength is 120mW / cm 2 .

[0292] In another embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 450 mJ / cm². 2UV intensity is 70mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 1000 mJ / cm². 2 Strength is 100mW / cm 2 .

[0293] In an exemplary embodiment, the preparation method further includes: performing an anti-fingerprint treatment on the surface of the first textured layer 27 to form an anti-fingerprint layer 29.

[0294] In this embodiment, the anti-fingerprint treatment can be as follows: applying an anti-fingerprint coating (AF) to the surface of the first texture layer 27, and then curing it by heating or ultraviolet irradiation to form an anti-fingerprint layer 29. The AF coating can be a coating containing fluoropolymers or siloxane compounds. The resulting anti-fingerprint layer 29 has extremely low surface energy, making it difficult for oil stains and fingerprints to adhere, thus improving the cleanliness of the shell surface.

[0295] In one exemplary embodiment, before performing optical coating treatment on the first paint film layer 20, the preparation method further includes:

[0296] Under the eighth preset condition, a printing process is performed on the first paint film layer 20 to form the second texture layer 28.

[0297] In this embodiment, a silicone head with a hardness of 65-75A can be used for printing. The size and structural dimensions of the silicone head are designed according to a 1:1 scale conformal or interference fit, with an outward expansion of 0.05. The printing equipment settings are as follows:

[0298] The master cylinder descent pressure is 95-105; the master cylinder descent speed is 95-105; the master cylinder ascent pressure is 95-105; the master cylinder ascent speed is 55-65; the master cylinder slow speed pressure is 145-155; the master cylinder slow speed is 45-55.

[0299] The mold core descending pressure is 95-105; the mold core descending speed is 55-65; the mold core rising pressure is 65-75; the mold core rising speed is 55-65; the mold core slow speed pressure is 60-70; the mold core slow speed is 5-10.

[0300] After the texture is imprinted, it can be cured twice; the first curing uses an LED light source with an energy of 250-450 mJ / cm². 2 UV intensity is 70-200mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 600-800 mJ / cm². 2 Strength is 90-120 mW / cm 2 .

[0301] For example, in one embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 250 mJ / cm². 2 UV intensity is 200mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 600 mJ / cm². 2 Strength is 120mW / cm 2 .

[0302] In another embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 350 mJ / cm². 2 UV intensity is 140mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 700 mJ / cm². 2 Strength is 100mW / cm 2 .

[0303] In another embodiment, the curing parameters for the two curing processes are as follows: the first curing uses an LED light source with an energy of 450 mJ / cm². 2 UV intensity is 70mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 800 mJ / cm². 2 The strength is 90mW / cm 2 .

[0304] In one exemplary embodiment, this disclosure provides an electronic device, which includes the housing as described above. The electronic device is, for example, a mobile phone, a laptop computer, a tablet computer, and a wearable device.

[0305] To more clearly explain the technical solution of this disclosure, specific embodiments of the shell preparation method are provided. The beneficial effects of selecting the above-mentioned range of component contents will be explained by providing specific experimental data through specific embodiments.

[0306] Example

[0307] Unless otherwise specified, the raw materials used in the following examples are all commercially available. The first filler comprises talc, matting agent, black paste, and white paste in a weight ratio of 2:1:2:25; the adhesion promoter is silane coupling agent KH560; the drier is cobalt drier; the solvent is butyl acetate; the curing agent is isocyanate; and the diluent is ethyl acetate. The second filler comprises blue paste, red paste, black paste, and white paste in a weight ratio of 1:1:2:25; the photoinitiator is 184 photoinitiator and TPO photoinitiator in a weight ratio of 4:1; the anti-sagging agent is a modified urea anti-sagging agent; the leveling agent is a polyether-modified polysiloxane leveling agent; the anti-settling paste is a modified urea anti-settling paste; the first polyester resin has a molecular weight of 20,000 and a glass transition temperature of 40°C; and the second polyester resin has a molecular weight of 30,000.

[0308] Example 1: A method for preparing a shell, comprising:

[0309] (1) Providing the body: After stacking five layers of glass fiber reinforced resin composite board, the body is molded for 480s at a molding temperature of 185℃ and a molding pressure of 200bar to obtain a body in which the main body and the protrusion are integrally molded. The radius R of the arc structure of the protrusion is 1.51mm, and the shortest distance H between the edge of the protrusion and the edge of the main body is 2.62mm.

[0310] (2) The fifth coating is applied to the surface of the substrate, leveled at 22°C for 5 min, and then dried at 70°C for 15 min to form a fifth paint film layer with a thickness of 8 μm. The fifth viscosity of the fifth coating is 26.7 mPa·s. The fifth coating includes a fifth main component, a curing agent, and a diluent in a weight ratio of 100:5:200; the fifth main component includes: 58 parts by weight of the second polyester resin; 30 parts by weight of the first filler; 4 parts by weight of the adhesion promoter; 0.5 parts by weight of the drying agent; and 1-5 parts by weight of the solvent.

[0311] (2) The sixth coating is applied to the surface of the fifth film layer, leveled at 22°C for 5 min, and then dried at 70°C for 15 min to form a sixth film layer with a thickness of 8 μm. The sixth viscosity of the sixth coating is 26.7 mPa·s. The sixth coating includes a sixth main component, a curing agent, and a diluent in a weight ratio of 100:20:80. The sixth main component includes: 5 parts by weight of thermoplastic acrylic resin; 5 parts by weight of polycarbonate glycol; 58 parts by weight of hydroxypropyl resin; 28 parts by weight of the second filler; 3 parts by weight of anti-settling agent; and 0.5 parts by weight of drying agent.

[0312] (3) The first coating is applied to the surface of the sixth film layer, leveled at 22°C for 5 min, and then dried at 55°C for 7 min to form a first film layer with a thickness of 25 μm. The first coating has a first viscosity of 30.0 mPa·s. The first coating comprises a first main component and a diluent in a weight ratio of 100:15. The first main component comprises: 20 parts by weight of multifunctional polyurethane acrylate; 10 parts by weight of difunctional polyurethane acrylate; 5 parts by weight of thermoplastic acrylic resin; 0 parts by weight of multifunctional UV-curable monomer; 1 part by weight of photoinitiator; 0.1 parts by weight of leveling agent; 2 parts by weight of anti-sagging agent; and 35 parts by weight of solvent. The multifunctional polyurethane acrylate comprises trifunctional polyurethane acrylate, quadrifunctional polyurethane acrylate, and nonfunctional polyurethane acrylate in a weight ratio of 0.67:0.67:1.

[0313] (4) A printing process is performed on the surface of the first paint film layer. The printing equipment parameters are as follows: main cylinder descent pressure 100; main cylinder descent speed 100; main cylinder rise pressure 100; main cylinder rise speed 60; main cylinder slow speed pressure 150; main cylinder slow speed 50; mold core descent pressure 100; mold core descent speed 60; mold core rise pressure 70; mold core rise speed 60; mold core slow speed pressure 65; mold core slow speed 8. After printing, two curing processes are performed to form the second texture layer. The curing parameters for the two processes are as follows: the first curing uses an LED light source with an energy of 350 mJ / cm². 2 UV intensity is 140mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 700 mJ / cm². 2 Strength is 100mW / cm 2 .

[0314] (5) Optical coating is performed on the second texture layer to form a Si / SiO2 / Nb2O5 / SiO2 / Nb2O5 / SiO2 / Nb2O5 coating layer with a thickness of 200nm.

[0315] (6) The second coating is applied to the surface of the coating layer, leveled at 22°C for 5 min, and then dried at 70°C for 15 min to form a second paint film layer with a thickness of 3 μm. The second viscosity of the second coating is 25.0 mPa·s. The second coating includes a second main component, a curing agent, and a diluent in a weight ratio of 100:2.5:200; the second main component includes: 25 parts by weight of the first polyester resin; 3 parts by weight of the adhesion promoter; and 80 parts by weight of the solvent.

[0316] (7) The third coating is applied to the surface of the second paint film layer, leveled at 22°C for 5 min, and then dried at 70°C for 15 min to form a third paint film layer with a thickness of 10 μm. The viscosity of the third coating is 26.7 mPa·s. The second coating includes a third main component, a curing agent, and a diluent in a weight ratio of 100:5:200; the third main component includes: 65 parts by weight of hydroxypropyl resin; 10 parts by weight of cellulose acetate butyrate; and 29 parts by weight of solvent.

[0317] (8) The fourth coating is applied to the surface of the third film layer, leveled at 22°C for 5 min, and then dried at 55°C for 7 min to form a fourth film layer with a thickness of 22 μm. The fourth viscosity of the fourth coating is 26.7 mPa·s. The fourth coating comprises a fourth main component and a diluent in a weight ratio of 100:50; the fourth main component comprises: 21 parts by weight of 3-functional polyurethane acrylate; 5 parts by weight of 4-functional polyurethane acrylate; 6 parts by weight of 6-functional modified polyurethane acrylate; 20 parts by weight of 9-functional polyurethane acrylate; 1.0 part by weight of leveling agent; 3 parts by weight of photoinitiator; and 45 parts by weight of solvent.

[0318] (9) A printing process is performed on the surface of the fourth paint film layer. The printing equipment settings are as follows: main cylinder descent pressure 100; main cylinder descent speed 100; main cylinder rise pressure 100; main cylinder rise speed 60; main cylinder slow speed pressure 150; main cylinder slow speed 50; mold core descent pressure 100; mold core descent speed 60; mold core rise pressure 70; mold core rise speed 60; mold core slow speed pressure 65; mold core slow speed 8. After printing, two curing processes are performed to form the first texture layer. The curing parameters for the two processes are as follows: the first curing uses an LED light source with an energy of 350 mJ / cm². 2 UV intensity is 140mW / cm 2 The second curing process uses an 80W high-pressure mercury lamp with an energy of 900 mJ / cm². 2 Strength is 120mW / cm 2 .

[0319] (10) Apply an anti-fingerprint treatment to the surface of the first texture layer to form an anti-fingerprint layer.

[0320] (11) The shell can be obtained by automatically machining the substrate with functional layers using Computerized Numerical Control (CNC).

[0321] To more clearly explain the technical solution of this disclosure, this disclosure also provides examples 2-14 of the shell preparation method, wherein the formulations of examples 2-14 are shown in Table 1.

[0322] Table 1 shows specific embodiments of the shell preparation parameters in this disclosure. It should be noted that, except for the parameters listed in Table 1, the other parameters in Examples 2-14 are essentially the same as those in Example 1. The viscosity of the coating can be adjusted by changing the ratio of the main component to the diluent.

[0323] Wherein, the ratio C1 is the weight ratio of trifunctional polyurethane acrylate, quadrifunctional polyurethane acrylate and nonfunctional polyurethane acrylate.

[0324] Table 1. Formulation parameters for the embodiments (unit: parts by weight)

[0325]

[0326] Table 1 (continued) Formulation Parameters for Examples (Unit: Parts by Weight)

[0327]

[0328]

[0329] Performance testing

[0330] The performance of the shells prepared in the examples was tested according to the following method, and the test results are recorded in Table 2.

[0331] 1. Appearance: Visually inspect the casing for any defects such as frame marks, fabric texture marks, or oil accumulation.

[0332] 2. Drop height: Place the shell with dimensions of 165×70mm on a rubber frame and fix it. Drop a 32g steel ball from a height of 40cm and observe whether microcracks appear on the surface of the shell. If no microcracks appear, increase the height by 5cm and continue the test until microcracks appear.

[0333] 3. Overall drop performance: After assembling the shell into a complete machine, directional drop and roller drop tests were conducted respectively. The micro-cracks on the shell surface were observed. 20 complete machines were tested in each group, and the number of micro-cracks appearing on the shell surface was recorded.

[0334] ① Directional drop test: The entire machine is dropped freely onto a marble floor from a height of 1m, and the micro-cracks in the shell are observed after two drops; each drop is performed in the following order: bottom / left / right / back / front / top / upper left corner / upper right corner / lower right corner / lower left corner.

[0335] ② Drum drop test: Place the entire machine in a drum and observe the micro-cracks on the surface of the casing after 1m / 100 tests.

[0336] Table 2 Performance Test Table of Shell

[0337]

[0338] Table 2 (continued) Performance Test Table for Housing

[0339]

[0340] Combining the data in Tables 1 and 2, it can be seen that the shell prepared using the method of this disclosure has a radius R of less than 2 mm for the arc-shaped structure of the crater protrusion, and a minimum distance H between the edge of the protrusion and the edge of the main body is less than 2.7 mm, which enriches the stacking and structural design. Furthermore, it can solve the appearance problems such as frame marks, fabric texture marks, and oil accumulation caused by hanging corner craters, and has excellent drop resistance. Among them, Examples 7-10 have better overall performance, indicating that by adjusting the formulation and viscosity value of each coating, the appearance and mechanical properties of the shell can be improved.

[0341] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

[0342] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A substrate for a shell, characterized in that, The substrate includes a body and a functional layer disposed on at least one side of the body. The functional layer includes a first paint film layer, which is coated with a first coating material. The viscosity value of the first coating material is within a first preset range.

2. The substrate for the shell according to claim 1, characterized in that, The first preset range is 28.3-31.7 mPa·s.

3. The substrate for a housing according to any one of claims 1-2, characterized in that, The first coating comprises a first main component, which includes the following raw materials in parts by weight:

4. The substrate for the housing according to claim 3, characterized in that, The multifunctional polyurethane acrylates include trifunctional, quadrifunctional, and nonfunctional polyurethane acrylates in a weight ratio of 0.67-3.60:0.67-3.00:

1.

5. The substrate for the housing according to claim 3, characterized in that, The first main component further includes 1-8 parts by weight of a photoinitiator; and / or Leveling agent 0.1-0.5 parts by weight; and / or Anti-sagging agent 2-7 parts by weight; and / or Solvent 35-46 parts by weight.

6. The substrate for a housing according to claim 1, characterized in that, The functional layer further includes a coating layer stacked on the side of the first coating layer facing away from the substrate; the coating layer includes a silicon elemental layer and an oxide layer.

7. The substrate for a housing according to claim 6, characterized in that, The functional layer further includes a second paint film layer stacked on the side of the coating layer opposite to the first paint film layer, the second paint film layer being coated with a second paint; the viscosity value of the second paint is within a second preset range. The second preset range is 23.3-26.7 mPa·s.

8. The substrate for a housing according to claim 7, characterized in that, The second coating comprises a second main component, which comprises the following raw materials in parts by weight: 20-28 parts by weight of the first polyester resin; Adhesion promoter 3-5 parts by weight; Solvent 70-80 parts by weight; The molecular weight of the first polyester resin is 10,000-30,000, and the glass transition temperature is 10-50℃.

9. The substrate for a housing according to claim 7, characterized in that, The functional layer further includes a third paint film layer stacked on the side of the second paint film layer away from the coating layer, the third paint film layer being coated with a third paint coating; the viscosity value of the third paint coating is within a third preset range. The third preset range is 24.1-29.1 mPa·s.

10. The substrate for a housing according to claim 9, characterized in that, The third coating comprises a third main component, which includes the following raw materials in parts by weight: 65-75 parts by weight of hydroxypropyl resin; 5-10 parts by weight of cellulose acetate butyrate; Solvent 11-29 parts by weight.

11. The substrate for a housing according to claim 9, characterized in that, The functional layer further includes a fourth paint film layer stacked on the side of the third paint film layer away from the second paint film layer, the fourth paint film layer being coated with a fourth paint; the viscosity value of the fourth paint is within a fourth preset range. The fourth preset range is 24.1-29.1 mPa·s.

12. The substrate for a housing according to claim 11, characterized in that, The fourth coating comprises a fourth main component, which includes the following raw materials in parts by weight:

13. The substrate for a housing according to claim 1, characterized in that, The functional layer further includes a fifth paint film layer stacked between the substrate and the first paint film layer, the fifth paint film layer being coated with a fifth paint; the viscosity value of the fifth paint is within a fifth preset range. The fifth preset range is 24.1-29.1 mPa·s.

14. The substrate for a housing according to claim 13, characterized in that, The fifth coating comprises a fifth main component, which includes the following raw materials in parts by weight:

15. The substrate for a housing according to claim 13, characterized in that, The functional layer further includes a sixth paint film layer stacked between the fifth paint film layer and the first paint film layer, the sixth paint film layer being coated with a sixth paint; the viscosity value of the sixth paint is within a sixth preset range. The sixth preset range is 24.1-29.1 mPa·s.

16. The substrate for a housing according to claim 15, characterized in that, The sixth coating comprises a sixth main component, which includes the following raw materials in parts by weight:

17. The substrate for a housing according to claim 11, characterized in that, The functional layer further includes a first texture layer stacked on the side of the fourth paint film layer opposite to the third paint film layer, an anti-fingerprint layer stacked on the first texture layer on the side of the first texture layer opposite to the fourth paint film layer, and a second texture layer stacked on the side of the first paint film layer opposite to the substrate.

18. A housing, characterized in that, The housing is made of the substrate as described in any one of claims 1-17, and the housing comprises: Main body; A protrusion is provided on the main body, the protrusion including an arc-shaped structure connected to the main body, the radius of the arc-shaped structure being 1.25-2.00 mm; The distance between the edge of the protrusion and the edge of the main body near the protrusion is 2.36-2.70 mm.

19. An electronic device, characterized in that, The electronic device includes the housing as described in claim 18.

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