Glass fiber mobile phone rear cover and manufacturing method

Abstract

The embodiment of the invention relates to the technical field of glass fiber mobile phone rear covers, and provides a glass fiber mobile phone rear cover and a manufacturing method thereof, and the method comprises the steps: 1, providing a base material which is a PET film; step 2, forming a release texture layer on the base material by using UV release glue; step 3, coating a dual-curing hardening liquid on the release texture layer, and carrying out baking and pre-curing treatment to form a hardening liquid layer; 4, forming a transfer printing inner texture layer on the hardening liquid layer by using UV transfer printing glue through a roll-to-roll transfer printing process; step 5, depositing a dielectric film layer of 30-300nm on the inner texture layer through magnetron sputtering; step 6, carrying out silk-screen processing on the dielectric film layer to form a silk-screen layer, and obtaining an initial thin film; and step 7, carrying out curing and mold pressing treatment on the prepared initial thin film to prepare the glass fiber mobile phone rear cover, so that the yield of the glass fiber mobile phone rear cover can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of glass fiber mobile phone back covers, and in particular to a glass fiber mobile phone back cover and a manufacturing method thereof. Background Art

[0002] With the development of technology and consumers' higher demand for portable electronic products, the requirements for lighter and thinner structural parts such as back covers are put forward. Therefore, it has become a hot topic to develop more materials with a specific gravity below 2.0 and a Young's modulus of 30GPa or even above 50GPa for the manufacture of mobile phone back covers. In this context, fiber-reinforced composite materials represented by glass fiber cloth reinforced epoxy resin materials have emerged. Among the many glass fiber board mobile phone back covers, the texture effect, especially the double texture effect glass fiber board mobile phone back covers have become the focus of many terminal brand ID / CMF design.

[0003] In the prior art, the fiberglass back cover with texture effect is often made by spraying and rubbing. In the existing scheme, since the control of each spraying process is crucial to the quality and performance of the final product, if the spraying thickness is too thick, the coating may crack or sag, and if it is too thin, it may affect the performance of the coating. In addition, dust will be released from time to time during the baking process, resulting in poor appearance during the spraying or rubbing process. The yield rate of mobile phone back shell products produced by the existing production method of fiberglass material is less than 60%. Therefore, a new manufacturing process and method of fiberglass mobile phone back cover is urgently needed. Summary of the invention

[0004] The embodiments of the present application provide a glass fiber mobile phone back cover and a manufacturing method, which can improve the yield rate of the glass fiber mobile phone back cover.

[0005] A first aspect of an embodiment of the present application provides a method for manufacturing a glass fiber mobile phone back cover, the method comprising:

[0006] Step 1, providing a substrate, wherein the substrate is a PET film;

[0007] Step 2, using UV release glue to form a release texture layer on the substrate;

[0008] Step 3, coating the release texture layer with a dual-curing hardening liquid and performing a baking pre-curing treatment to form a hardening liquid layer;

[0009] Step 4, forming a transfer inner texture layer on the hardened liquid layer by a roll-to-roll transfer process using UV transfer glue;

[0010] Step 5, depositing a dielectric film layer of 30 to 300 nm on the inner texture layer by magnetron sputtering;

[0011] Step 6, performing a silk screen process on the dielectric film layer to form a silk screen layer to obtain an initial thin film;

[0012] Step 7, subjecting the initial film obtained above to curing and molding to obtain a glass fiber mobile phone back cover.

[0013] In a possible implementation, the thickness of the substrate is 0.1-0.2 mm.

[0014] In a possible implementation, the step of using UV release glue to form a release texture layer on the substrate includes:

[0015] A roll-to-roll transfer process is adopted and UV release glue is used to form a release texture layer on the substrate.

[0016] In a possible implementation, the dielectric film layer comprises zirconium oxide, silicon oxide, and niobium oxide, and the film layer structure is ZrO x / SiO y / NbO z .

[0017] In a possible implementation, performing a silk screen process on the dielectric film layer to form a silk screen layer to obtain an initial thin film includes:

[0018] The roll-to-roll screen printing process is adopted to screen print 3 to 5 times on the dielectric film layer to sequentially form an effect ink layer, a cover bottom ink layer and an adhesive ink layer to obtain an initial film.

[0019] In a possible implementation, the initial film prepared above is subjected to a molding and curing process with a glass fiber epoxy resin prepreg / prepreg to prepare a glass fiber mobile phone back cover, comprising:

[0020] Cutting the initial film prepared above into a preset size and laminating and combining it with the glass fiber epoxy resin prepreg to obtain an assembly;

[0021] Placing the assembly in a mold for molding to form an intermediate part in a 2D or 3D form;

[0022] Removal of substrate and release texture layer from 2D or 3D shaped intermediate parts followed by UV light curing;

[0023] The fiberglass mobile phone back cover is processed into the size of the fiberglass mobile phone back cover by CNC to obtain the fiberglass mobile phone back cover.

[0024] In a possible implementation, the release texture layer has a thickness of 12 to 18 micrometers.

[0025] In a possible implementation, the thickness of the transferred inner texture layer is 12 to 18 micrometers.

[0026] In a possible implementation, the thickness of the effect ink layer is 6 to 8 micrometers, the thickness of the cover ink layer is 18 to 24 micrometers, and the thickness of the adhesive ink layer is 6 to 8 micrometers.

[0027] A second aspect of an embodiment of the present application provides a glass fiber mobile phone back cover, wherein the glass fiber mobile phone back cover is made by the method described in any one of the first aspects.

[0028] The glass fiber back cover manufacturing process proposed in this application has the following advantages:

[0029] 1. Excellent surface properties, the surface pencil hardness of the product is 3H and above (Mitsubishi pencil, 750g force), and the steel wool wear resistance is more than 500 times (0000# steel wool, 1 kg force);

[0030] 2. CMF has good effect, and can achieve double texture + PVD effect, and the PVD coating is on the lower layer of the inner texture, which can better present the texture effect (in the spraying + rubbing process, the PVD layer is located on the upper layer of the inner texture layer, which will cover the inner texture to a certain extent, especially the thick coating or bright silver effect);

[0031] 3. Low manufacturing cost and environmental friendliness. Using silk screen printing instead of spraying and transfer printing instead of rubbing can greatly reduce manufacturing costs. In addition, the VOC emission during the manufacturing process is greatly reduced, which is more environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic flow chart of a method for manufacturing a fiberglass mobile phone back cover is provided for an embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0035] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0036] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0037] In order to better understand the method for manufacturing a glass fiber mobile phone back cover provided in the embodiment of the present application, the existing method for manufacturing a glass fiber mobile phone back cover is first briefly introduced below.

[0038] See also Figure 1 , Figure 1 The present invention provides a process flow diagram of a method for manufacturing a glass fiber mobile phone back cover. Figure 1 As shown, the method for making a glass fiber mobile phone back cover includes:

[0039] Step 1, providing a substrate, wherein the substrate is a PET film;

[0040] Step 2, using UV release glue to form a release texture layer on the substrate;

[0041] Step 3, coating the release texture layer with a dual-curing hardening liquid and performing a baking pre-curing treatment to form a hardening liquid layer;

[0042] Step 4, forming a transfer inner texture layer on the hardened liquid layer by a roll-to-roll transfer process using UV transfer glue;

[0043] Step 5, depositing a 30-300 nm dielectric film layer on the inner texture layer by magnetron sputtering;

[0044] Step 6, performing a silk screen process on the dielectric film layer to form a silk screen layer to obtain an initial thin film;

[0045] Step 7, subjecting the initial film obtained above to curing and molding to obtain a glass fiber mobile phone back cover.

[0046] Wherein, the thickness of the substrate is 0.1-0.2 mm.

[0047] In step 7, the following manufacturing process may be specifically performed:

[0048] Cutting the initial film prepared above into a preset size and laminating and combining it with the glass fiber epoxy resin prepreg to obtain an assembly;

[0049] Placing the assembly in a mold for molding to form an intermediate part in a 2D or 3D form;

[0050] Removal of substrate and release texture layer from 2D or 3D shaped intermediate parts followed by UV light curing;

[0051] The fiberglass mobile phone back cover is processed into the size of the fiberglass mobile phone back cover by CNC to obtain the fiberglass mobile phone back cover.

[0052] Specifically, the assembly includes a glass fiber epoxy resin prepreg layer formed by glass fiber epoxy resin prepreg, which may be provided with 3-5 layers and the total thickness may be 0.3-0.5 mm.

[0053] In a possible implementation, forming the release texture layer on the substrate using UV release glue includes: adopting a roll-to-roll transfer process and using UV release glue to form the release texture layer on the substrate.

[0054] In a possible implementation, the dielectric film layer comprises zirconium oxide, silicon oxide, and niobium oxide, and the film layer structure is ZrO x / SiO y / NbO z .

[0055] In one possible implementation, screen printing is performed on the dielectric film layer to form a screen printing layer to obtain an initial film, including: using a roll-to-roll screen printing process to screen print 3 to 5 times on the dielectric film layer to sequentially form an effect ink layer, a cover ink layer and an adhesive ink layer to obtain an initial film.

[0056] In a possible implementation, the release texture layer has a thickness of 12-18 microns.

[0057] In a possible implementation, the thickness of the transferred inner texture layer is 12-18 microns.

[0058] In a possible implementation, the thickness of the effect ink layer is 6-8 micrometers, the thickness of the cover bottom ink layer is 18-24 micrometers, and the thickness of the bonding ink layer is 6-8 micrometers.

[0059] The glass fiber back cover manufacturing process proposed in this application has the following advantages:

[0060] 1. Excellent surface properties, the surface pencil hardness of the product is 3H and above (Mitsubishi pencil, 750g force), and the steel wool wear resistance is more than 500 times (0000# steel wool, 1 kg force);

[0061] 2. CMF has good effect, and can achieve double texture + PVD effect, and the PVD coating is on the lower layer of the inner texture, which can better present the texture effect (in the spraying + rubbing process, the PVD layer is located on the upper layer of the inner texture layer, which will cover the inner texture to a certain extent, especially the thick coating or bright silver effect);

[0062] 3. Low manufacturing cost and environmental friendliness. Using silk screen printing instead of spraying and transfer printing instead of rubbing can greatly reduce manufacturing costs. In addition, the VOC emission during the manufacturing process is greatly reduced, which is more environmentally friendly.

[0063] Example 1

[0064] A 0.25 mm BOPET film was selected, and a transfer process was adopted. The flash sand texture (external texture release layer) was transferred using UV release glue, and then the hardening liquid 027 (60% solid content, double-curing hardening liquid) was coated with a thickness of 25 ± 2 microns. The baking condition was 70 ° C for 30 min. Then, a layer of intermediate varnish was screen-printed on the surface of the hardening liquid with a thickness of 5 to 8 microns. Then, the lens pattern was transferred using the inner texture transfer glue on the surface of the varnish. Then, PVD coating was performed, and the thickness of the coating layer was 80 nm for brightening. Then, The surface of the coating was screen-printed with effect ink and baked at 80°C for 30 minutes, followed by screen printing of white ink twice, black ink once, and bonding ink once, and finally baked at 80°C for 2 hours. The above film was laminated with 3 sheets of 0.1 glass fiber epoxy resin prepreg (the lamination angles were 45° / 0 / -45° respectively), cured at 150°C for 1 hour, and after cooling to room temperature, the base film and release layer on the surface were torn off to expose the surface texture (flash sand), and UV (high-pressure mercury lamp, energy of 600-800mJ / cm 2 ) secondary curing, followed by CNC processing, and the finished product is obtained after full inspection and packaging. The surface has the effect of internal and external texture and coating. The overall thickness of the product is 0.38mm. The surface hardness and steel wool wear resistance of the finished product are tested, and the results are shown in Table 1.

[0065] Example 2

[0066] Select 0.125mm BOPET film, adopt the transfer process, use UV release glue to transfer the flash sand texture (external texture release layer), then apply hardening liquid 027 (60% solid content, dual-curing hardening liquid), the thickness is 20±2 microns, the baking condition is 70℃30min, then screen print a layer of intermediate layer varnish on the surface of the hardening liquid, the thickness is 5-8 microns, then use the inner texture transfer glue to transfer the Fresnel lens pattern on the surface of the varnish, then PVD coating, the thickness of the coating layer is 200nm optical film, then screen print effect ink on the surface of the coating, bake at 80℃30min, then screen print white ink twice, black ink once, bonding layer ink once, and finally 80℃ After baking for 2 hours, another 5 sheets of 0.1mm glass fiber epoxy resin prepreg (fast curing system) were laminated (the lamination angles were 45° / -45° / 0 / 45° / -45° respectively), placed in a hot pressing mold, hot pressed at 150°C for 5 minutes, and a pressure of 120Ton. After cooling to room temperature, the molded 3D material was taken out for use (thickness of 0.45mm), and a layer of thermosetting epoxy glue was silk-screened on the ink on the above-made membrane. The molded material and the membrane were placed in a vacuum bonding equipment for bonding. After bonding, the base film and release layer on the surface were torn off to expose the surface texture (flash sand), and UV (high-pressure mercury lamp, energy of 600-800mJ / cm 2 ) secondary curing, followed by CNC processing, and the finished product is obtained after full inspection and packaging. The surface has the effect of internal and external texture and coating. The overall thickness of the product is about 0.55mm. The surface hardness and steel wool wear resistance of the finished product are tested, and the results are shown in Table 1.

[0067] Example 3

[0068] A 0.1mm thick TPU film + 0.188mm BOPET composite film was selected, and a transfer process was adopted. The flash sand texture (external texture release layer) was transferred on the TPU film using UV release glue, and then the hardening liquid 027 (60% solid content, dual-curing hardening liquid) was applied with a thickness of 18±2 microns. The baking condition was 70℃30min. Then, a layer of intermediate varnish was screen-printed on the surface of the hardening liquid with a thickness of 5-8 microns. Then, the bullet pattern was transferred on the surface of the varnish using the inner texture transfer glue, and then PVD coating was performed. The thickness of the coating layer was an optical film (gold) of 260nm. Then, the effect ink was screen-printed on the surface of the coating, and the coating was baked at 80℃30min. Then, white ink was screen-printed twice. Black ink once, adhesive layer ink once, and finally baked at 80℃ for 2 hours. Another 3 sheets of 0.10mm glass fiber epoxy resin prepreg (fast curing system) were laminated (laminated angles were 45° / 0 / -45° respectively), placed in a hot pressing mold, hot pressed at 150℃ for 5 minutes, and a pressure of 120Ton. After cooling to room temperature, the molded 3D material was taken out for use (thickness of 0.28mm), and a layer of thermosetting epoxy glue was silk-screened on the ink on the above-mentioned membrane. The molded material and the membrane were placed in a vacuum bonding equipment for bonding. After bonding, the base film and release layer on the surface were torn off to expose the surface texture (flash sand), and UV (high-pressure mercury lamp, energy of 600-800mJ / cm 2 ) secondary curing, followed by CNC processing, and the finished product is obtained after full inspection and packaging. The surface has the effect of internal and external texture and coating. The overall thickness of the product is about 0.35mm. The surface hardness and steel wool wear resistance of the finished product are tested, and the results are shown in Table 1.

[0069] Comparative Example 1

[0070] First, select 5 sheets of 0.10mm glass fiber epoxy resin prepreg (fast curing system) for stacking (stack angles are 45° / -45° / 0 / 45° / -45° respectively), place them in a hot pressing mold, hot press at 150℃ for 5 minutes, and the pressure is 120Ton. After cooling to room temperature, take out the molded 3D material for use. For the molded 3D glass fiber material, spray 8~12μm on the glass fiber board. primer (solid content 20wt%) to provide good adhesion for the subsequent base coating; spray 15-20μm primer (solid content 40wt%) on the primer surface to provide a uniform base for the subsequent spraying; spray 15-25μm UV coating (solid content 40wt%) on the primer, and after baking, the material sprayed with UV coating is bonded to the 3D silicone optical mold (lens pattern), and UV curing is performed after bonding (this process is called rubbing), and then spray the middle coating color paint, spray UV topcoat on the middle coating color paint, and use the rubbing process to use UV topcoat (solid content 50wt%) to rub the outer texture (flash sand), and then perform secondary curing, and then perform full inspection packaging and molding after CNC, and the surface of the finished product is tested for pencil hardness and steel wool wear resistance, and the results are shown in Table 1.

[0071] Comparative Example 2

[0072] First, select 5 sheets of 0.10mm glass fiber epoxy resin prepreg (fast curing system) for stacking (stack angles are 45° / -45° / 0 / 45° / -45° respectively), place them in a hot pressing mold, hot press at 150℃ for 5 minutes, and the pressure is 120Ton. After cooling to room temperature, take out the molded 3D material for use. For the molded 3D glass fiber material, spray 8~12μm on the glass fiber board. primer (solid content 20wt%) to provide good adhesion for the subsequent bottom coating; spray 15-20μm primer (solid content 40wt%) on the primer surface to provide a uniform base for the subsequent spraying; spray 15-25μm UV coating (solid content 40wt%) on the primer, and after baking, the material sprayed with UV coating is bonded to the 3D silicone optical mold (lens pattern), and UV curing (this process is called rubbing) is performed after bonding, followed by PVD electroplating, the coating is 80nm brightening, and 6-8μm primer (solid content 20wt%) is continued to be sprayed, and then the middle coating color paint is sprayed, and UV topcoat is sprayed on the middle coating color paint. The outer texture (flash sand) is rubbed using UV topcoat (solid content 50wt%) by rubbing technology, and then secondary curing is performed. After CNC, full inspection packaging and molding are performed, and the surface of the finished product is tested for pencil hardness and steel wool wear resistance. The results are shown in Table 1.

[0073] Table 1 Experimental example comparison table

[0074] plan Yield Pencil hardness Steel wool is wear-resistant VOC Release Example 1 85％ 4H 1500 times 1.8~2.2g / pcs Example 2 80％ 3H 1000 times 1.6~1.8g / pcs Example 3 78％ 3H 1000 times 1.5~1.7g / pcs Comparative Example 1 60％ 2H 500 times 10~12g / pcs Comparative Example 2 30％ 1H 300 times 12~14g / pcs

[0075] It can be seen from Table 1 that the embodiments of the present application are superior to the solutions in the comparative examples and therefore have better feasibility.

[0076] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0077] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0078] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for making a glass fiber mobile phone back cover, characterized in that: The method comprises: Step 1, providing a substrate, wherein the substrate is a PET film; Step 2, using UV release glue to form a release texture layer on the substrate; Step 3, coating the release texture layer with a dual-curing hardening liquid and performing a baking pre-curing treatment to form a hardening liquid layer; Step 4, forming a transfer inner texture layer on the hardened liquid layer by a roll-to-roll transfer process using UV transfer glue; Step 5, depositing a 30-300 nm dielectric film layer on the inner texture layer by magnetron sputtering; Step 6, performing a silk screen process on the dielectric film layer to form a silk screen layer to obtain an initial thin film; Step 7, subjecting the initial film obtained above to curing and molding to obtain a glass fiber mobile phone back cover.

2. The method for making a glass fiber mobile phone back cover according to claim 1, characterized in that: The thickness of the substrate is 0.1-0.2 mm.

3. The method for making a glass fiber mobile phone back cover according to claim 2, characterized in that: The method of using UV release glue on the substrate to form a release texture layer comprises: A roll-to-roll transfer process is adopted and UV release glue is used to form a release texture layer on the substrate.

4. The method for manufacturing a glass fiber mobile phone back cover according to any one of claims 1 to 3, characterized in that: The dielectric film layer comprises zirconium oxide, silicon oxide and niobium oxide, and the film layer structure is ZrO x / SiO y / NbO z .

5. The method for making a glass fiber mobile phone back cover according to claim 4, characterized in that: The method of performing silk screen processing on the dielectric film layer to form a silk screen layer to obtain an initial thin film comprises: The roll-to-roll screen printing process is adopted to screen print 3 to 5 times on the dielectric film layer to sequentially form an effect ink layer, a cover bottom ink layer and an adhesive ink layer to obtain an initial film.

6. The method for making a glass fiber mobile phone back cover according to claim 5, characterized in that: The initial film prepared above is subjected to curing and molding treatment to prepare a glass fiber mobile phone back cover, comprising: Cutting the initial film prepared above into a preset size and laminating and combining it with the glass fiber epoxy resin prepreg to obtain an assembly; Placing the assembly in a mold for molding to form an intermediate part in a 2D or 3D form; Remove substrate and release texture layer from 2D or 3D shaped intermediate parts; The fiberglass mobile phone back cover is processed into the size of the fiberglass mobile phone back cover by CNC to obtain the fiberglass mobile phone back cover.

7. The method for making a glass fiber mobile phone back cover according to claim 6, characterized in that: The thickness of the release texture layer is 12-18 microns.

8. The method for manufacturing a glass fiber mobile phone back cover according to any one of claims 4 to 6, characterized in that: The thickness of the transfer inner texture layer is 12-18 microns.

9. The method for manufacturing a glass fiber mobile phone back cover according to any one of claims 5 to 7, characterized in that: The thickness of the effect ink layer is 6-8 microns, the thickness of the cover bottom ink layer is 18-24 microns, and the thickness of the bonding ink layer is 6-8 microns.

10. A fiberglass mobile phone back cover, characterized in that: The glass fiber mobile phone back cover is prepared by the method according to any one of claims 1 to 8.

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