Rear cover of electronic equipment

Abstract

The utility model relates to the technical field of electronic equipment, in particular to a rear cover of electronic equipment. The electronic equipment rear cover comprises a cover main body, and a first bonding layer, a main body ink layer, a UV liquid crystal layer, a second bonding layer, a magnetic ink layer and a protective layer which are sequentially arranged on the cover main body. The cover main body plays a role in bearing, the main body ink layer is adhered to the cover main body, and then the UV liquid crystal layer, the second adhesive layer, the magnetic ink layer and the protective layer are sequentially arranged on the main body ink layer. The magnetic ink layer and the UV liquid crystal layer are combined and attached to the cover body, on one hand, the UV liquid crystal layer has the imitation electroplating texture, the magnetic ink layer has the three-dimensional dynamic effect, after combination, texture light and shadow change along with light movement, and the flash sand particle texture is high; on the other hand, after the magnetic ink layer is attached to the UV liquid crystal layer, PVD electroplating does not need to be carried out, the texture similar to metal and ceramic materials can be shown, investment of PVD coating equipment is saved, the technology is simplified, and cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic devices, in particular to a rear cover of an electronic device. Background Art

[0002] The mobile phone rear cover is one of the main structural parts of a mobile phone. At present, most of the mobile phone rear covers made of plates adopt UV transfer printing texture and coating PVD to achieve a colorful effect. However, to achieve an optical colorful effect, it generally requires investing in a lithography machine to make a texture mold, and using magnetron sputtering or an electron gun to coat the PVD coating effect. The equipment cost investment is large and the efficiency is low.

[0003] For example, Chinese Patent Application No.: CN202123086185.7 discloses a composite board mobile phone rear cover. Specifically, it discloses that "the inner layer can achieve a colorful decorative effect through processes such as UV transfer printing / PVD / screen printing". This process has a large equipment cost investment and low efficiency. Summary of the Utility Model

[0004] In view of this, in view of the deficiencies of the existing technology, the utility model provides a rear cover of an electronic device. The manufacturing process of this rear cover is simple, the equipment investment is low, and the production efficiency is high, thus overcoming the deficiencies of the existing technology.

[0005] To achieve the above purpose, the specific technical solutions adopted by the utility model are as follows:

[0006] This application provides a rear cover of an electronic device, including a cover main body, and a first adhesive layer, a main body ink layer, a UV liquid crystal layer, a second adhesive layer, a magnetic ink layer, and a protective layer sequentially arranged on the cover main body.

[0007] Preferably, the protective layer is one or a combination of multiple layers of polyurethane acrylate resin, epoxy acrylate, and polyester acrylate resin, and its thickness is between 10 - 30 µm.

[0008] Preferably, the magnetic ink layer is one of polyester resin magnetic ink, polyurethane acrylate resin magnetic ink, and epoxy resin magnetic ink, and its thickness is between 8 - 15 µm.

[0009] Preferably, the second adhesive layer is acrylic resin or epoxy resin.

[0010] Preferably, the UV liquid crystal layer is a cholesteric liquid crystal molecule layer and a polyurethane acrylate resin layer stacked together.

[0011] Preferably, the main body ink layer has 3 - 5 layers, and its overall thickness is between 30 - 40 µm.

[0012] Preferably, the main body ink layer is polyester resin ink or epoxy resin ink.

[0013] Preferably, the first adhesive layer is acrylic resin or epoxy resin, and its thickness ranges from 15 to 25 µm.

[0014] Preferably, the cover body is a fitting made of one of the materials such as glass fiber, carbon fiber composite material, and plastic.

[0015] Preferably, a release layer and a substrate layer are sequentially arranged on the outer side of the protective layer.

[0016] Compared with the prior art, the present utility model has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solutions, the cover body plays a role of bearing. The main body ink layer is adhered to the cover body, and then a UV liquid crystal layer, a second adhesive layer, a magnetic ink layer, and a protective layer are sequentially arranged on the main body ink layer. On the one hand, the UV liquid crystal layer has an imitation electroplating texture effect, and the magnetic ink layer is different from the existing transferred UV texture and can present a three-dimensional dynamic effect. After the two are combined, the texture light and shadow change with the movement of light, and the flash sand particle texture is strong. On the other hand, after the magnetic ink layer is attached to the UV liquid crystal layer, it can present a texture similar to that of metal and ceramic materials without PVD electroplating, thus saving the investment in PVD electroplating equipment, simplifying the process, and reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the layered structure of Embodiment 1 of the present utility model.

[0018] Figure 2 is a schematic diagram of the effect of Embodiment 1 of the present utility model.

[0019] Figure 3 is of Embodiment 1 of the present utility model Figure 2 schematic diagram from another angle.

[0020] Figure 4 is a schematic diagram of the layered structure of Embodiment 2 of the present utility model.

[0021] DESCRIPTION OF THE REFERENCE NUMERALS:

[0022] 10. Cover body; 11. Camera hole; 12. Volume key; 13. Power key; 11. First adhesive layer; 12. Main body ink layer; 13. UV liquid crystal layer; 14. Second adhesive layer; 15. Magnetic ink layer; 16. Protective layer; 17. Release layer; 18. Substrate layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to further elaborate on the technical means and effects adopted by the present utility model to achieve the predetermined utility model purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific embodiments, structures, features, and their effects of the present utility model as follows.

[0024] Embodiment 1

[0025] Please refer to Figures 1 to 3 as shown, which shows the specific structure of the preferred embodiment of the present utility model, and is a rear cover of an electronic device.

[0026] Among them, the magnetic ink layer 15 is combined with the UV liquid crystal layer 13 and laminated on the cover body 10. On the one hand, it can present a three-dimensional dynamic effect, and the texture light and shadow can change with the movement of light. On the other hand, after laminating the UV liquid crystal layer 13, there is no need for PVD electroplating, and it can also present a texture similar to that of metal and ceramic materials, saving the investment in PVD electroplating equipment, simplifying the process, and reducing the cost.

[0027] The present application provides a rear cover of an electronic device, including a cover body 10, and a first adhesive layer 11, a main body ink layer 12, a UV liquid crystal layer 13, a second adhesive layer 14, a magnetic ink layer 15, and a protective layer 16 that are sequentially arranged on the cover body 10. The cover body 10 plays a bearing role. The first adhesive layer 11 can play an adhesive role and can firmly adhere the main body ink layer 12 to the cover body 10. The main body ink layer 12 has a certain color. The UV liquid crystal layer 13 has an imitation electroplating texture effect. The combination of the magnetic ink 3D pattern and the imitation electroplating effect makes the rear cover more colorful. The second adhesive layer 14 helps to firmly adhere the magnetic ink layer 15 to the UV liquid crystal layer 13. The protective layer 16 has high hardness and excellent scratch resistance, providing effective protection for the rear cover.

[0028] Preferably, the protective layer 16 is one or a multi-layer combination of polyurethane acrylate resin, epoxy acrylate, and polyester acrylate resin, and its thickness is between 10 - 30 µm. The thickness of the protective layer 16 can be any value, such as 10 µm, 15 µm, 20 µm, 25 µm, 30 µm. The protective layer 16 can be cured by UV lamp, thermal curing, or dual curing of UV curing and thermal curing. Among them, UV curing has a fast speed and can be rapidly formed. When the protective layer 16 is multi-layer, it can be any two or a layered structure of a combination of three of polyurethane acrylate resin, epoxy acrylate, and polyester acrylate resin.

[0029] Preferably, the magnetic ink layer 15 is one of polyester resin magnetic ink, polyurethane acrylate resin magnetic ink, and epoxy resin magnetic ink, and its thickness ranges from 8 to 15 µm. The magnetic powder selected for the magnetic ink layer 15 (magnetic printing ink) is a nano-layered pigment, and the nano-layered structure contains magnetizable components such as Fe, Co, and Ni. The magnetic ink layer 15 can be cured by heat or UV light. In this embodiment, the magnetic ink layer 15 is preferably cured by UV. The acrylic resin or epoxy resin in the magnetic ink layer 15 can be quickly cured by UV, which is beneficial to improving production efficiency. Under the action of a magnetic mold, the magnetic ink layer 15 is arranged to form a specific 3D pattern, and the pattern is fixed after the ink is cured. Matching with the UV liquid crystal layer 13 can achieve a colorful effect.

[0030] Preferably, the second adhesive layer 14 is acrylic resin or epoxy resin. The second adhesive layer 14 is a type of UV glue, which can be quickly cured by an ultraviolet lamp (UV). It has a fast curing speed and high production efficiency.

[0031] Preferably, the UV liquid crystal layer 13 is a cholesteric liquid crystal molecule layer and a polyurethane acrylate resin layer stacked together. It is cured quickly by an ultraviolet lamp (UV), with a fast curing speed and high production efficiency. Cholesteric liquid crystal molecules are named because the cholesteric phase is derived from cholesteryl derivatives. Such liquid crystal molecules are flat and arranged in layers. The molecules within the layer are parallel to each other, and the long axis of the molecules is parallel to the layer plane. The long axis directions of the molecules in different layers change slightly and are arranged in a helical structure along the normal direction of the layer. The pitch of the cholesteric liquid crystal is about 300 nm, which is of the same order of magnitude as the wavelength of visible light. This pitch will change with different external temperature and electric field conditions. Therefore, the external light can be modulated by adjusting the pitch. Cholesteric liquid crystals are very useful in display technology. They are widely used as additives for nematic liquid crystals and can guide the liquid crystals to twist and arrange along the surface of the liquid crystal cell at 180º, 270º, etc., to form a super-twisted (STN) display.

[0032] Preferably, the main ink layer 12 has 3 to 5 layers, and its overall thickness ranges from 30 to 40 µm. Different numbers of main layers can produce different color effects. At the same time, the main ink layer 12 is printed in multiple times, which is beneficial to ensuring the quality of the ink layer. In this embodiment, the overall thickness of the main ink layer 12 can be any value among 30 µm, 35 µm, and 40 µm.

[0033] Preferably, the main ink layer 12 is polyester resin ink or epoxy resin ink. The main ink layer 12 contains specific pigments and can achieve diverse colors and effects.

[0034] Preferably, the first adhesive layer 11 is made of acrylic resin or epoxy resin, and its thickness ranges from 15 to 25 µm. The first adhesive layer 11 is cured by a UV lamp, which is beneficial to improving the curing efficiency, and its thickness can be any value among 15 µm, 20 µm, and 25 µm.

[0035] Preferably, the cover body 10 is a component made of glass fiber, carbon fiber composite material, or plastic material. In this embodiment, the cover body 10 is preferably made of a glass fiber epoxy resin composite material. The thickness of the cover body 10 ranges from 0.3 to 0.8 mm.

[0036] The cover body 10 has a back plate and a frame. A camera hole 11 is provided on the back plate, and a volume button 12 and a power button 13 are provided on the frame.

[0037] This embodiment provides a production process for the back cover of an electronic device: using materials such as PO and PET films as the base material 18 → coating the release layer 17 (transferring the outer texture) → coating / spraying the protective layer 16 → screen printing the magnetic ink layer 15 → arranging the above materials on a magnetic mold to form a magnetic ink texture → laminating the UV liquid crystal layer 13 → screen printing the main ink layer 12 → coating the first adhesive layer 11 → vacuum laminating the 3D / 4D glass fiber back cover → peeling off the release layer 17 → UV curing → CNC.

[0038] Specifically as follows:

[0039] Step 1: The base material layer 18 uses a stretchable film (PO film, PET film, or other materials) as the base material, and the release layer 17 is transferred. (After the final lamination of the product is completed, the release layer 17 and the base material layer 18 will be peeled off, and the base layer 18 and the release layer do not adhere to the surface of the product.) The release layer 17 is made of a special modified acrylic resin and is cured by UV, with excellent stretching properties, good release effect, and no residual glue on the texture.

[0040] Step 2: Coat or spray a hardening liquid on the base material with the release layer 17. The transmittance of the hardening liquid is greater than 90%. The hardening liquid uses a dual-curing resin system of thermal curing and UV curing. After coating and spraying the hardening liquid, the hardening liquid is thermally cured to form the protective layer 16. First, thermally cure the protective layer 16 to a semi-cured state, which has high stretching and no cracking properties.

[0041] Step 3: After screen printing the magnetic ink layer 15 on the protective layer 16, place it on a magnetic template and generate a texture by magnetic field alignment. The magnetic ink resin can be thermosetting or UV-cured using a UV-type resin.

[0042] Step 4: Laminating the UV liquid crystal layer 13 on the magnetic ink layer 15 with the second adhesive layer 14.

[0043] Step 5: Screen-print the main ink layer 12 on the UV liquid crystal layer 13. The main ink layer 12 is screen-printed in multiple times and baked for drying.

[0044] Step 6: Coat the first adhesive layer 11 on the main ink layer 12.

[0045] Step 7: Use a vacuum laminating machine to complete the lamination of the 3D / 4D cover body 10 and the composite film produced by the above process.

[0046] Step 8: After the lamination is completed, tear off the base layer 18 dielectric film and the release layer 17. The magnetic ink texture with the protective layer 16 is firmly attached to the surface of the 3D or 4D cover body 10 in combination with the UV liquid crystal effect layer. After UV curing, the hardening liquid is completely cured to form a protective layer with high hardness and high wear resistance.

[0047] Step 9: After the lamination and curing are completed, complete the cutting of the product size and shape according to the product size requirements by CNC.

[0048] Embodiment 2

[0049] Please refer to Figure 4 As shown, a release layer 17 and a base material layer 18 are sequentially provided on the outside of the protective layer 16. The release layer 17 and the base material layer 18 are used to improve the production efficiency of the electronic device back cover. During production, the release layer 17 is arranged on the base material layer 18, and then the protective layer 16, the magnetic ink layer 15, the second adhesive layer 14, the UV liquid crystal layer 13, the main ink layer 12, and the first adhesive layer 11 are sequentially arranged to form a composite film with a multi-layer structure. After lamination, the release layer 17 and the base material layer 18 will be torn off; the first adhesive layer 11 is pasted on the cover body 10.

[0050] In summary, the design focus of the present utility model is that it is attached to the cover body 10 through the magnetic ink layer 15 combined with the UV liquid crystal layer 13, achieving the effect that the texture and light and shadow can change with the movement of light, and the flash sand particle texture is strong. It does not require PVD electroplating and can also present a texture similar to that of metal and ceramic, saving the investment in PVD electroplating equipment, simplifying the process, and reducing the cost.

[0051] The above is only a preferred embodiment of the present utility model and does not impose any form of limitation on the present utility model. Although the present utility model has been disclosed above with the preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content within the scope of the technical solution of the present utility model to make equivalent embodiments with equivalent changes, but as long as it does not depart from the technical solution content of the present utility model, any brief modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. A rear cover of an electronic device, characterized in that: It includes a cover body, and a first adhesive layer, a main body ink layer, a UV liquid crystal layer, a second adhesive layer, a magnetic ink layer, and a protective layer that are sequentially arranged on the cover body; the UV liquid crystal layer is a cholesteric liquid crystal molecule layer and a polyurethane acrylate resin layer stacked together.

2. The back cover of an electronic device according to claim 1, characterized in that: The protective layer is one or a combination of multiple layers of polyurethane acrylate resin, epoxy acrylate, and polyester acrylate resin, and its thickness is between 10 - 30 µm.

3. The back cover of an electronic device according to claim 1, characterized in that: The magnetic ink layer is one of polyester resin magnetic ink, polyurethane acrylate resin magnetic ink, and epoxy resin magnetic ink, and its thickness is between 8 - 15 µm.

4. The back cover of an electronic device according to claim 1, characterized in that: The second adhesive layer is acrylic resin or epoxy resin.

5. An electronic device back cover according to claim 1, characterized in that: The main body ink layer has 3 - 5 layers, and its overall thickness is between 30 - 40 µm.

6. The back cover of an electronic device according to claim 5, wherein: The main body ink layer is polyester resin ink or epoxy resin ink.

7. The back cover of an electronic device according to claim 1, characterized in that: The first adhesive layer is acrylic resin or epoxy resin, and its thickness is between 15 - 25 µm.

8. The back cover of an electronic device according to claim 1, characterized in that: The cover body is a fitting made of one of glass fiber, carbon fiber composite material, and plastic.

9. An electronic device rear cover according to any one of claims 1-8, characterized in that: An isolation layer and a base material layer are sequentially arranged on the outer side of the protective layer.

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