Shell, preparing method and application thereof in electronic product

0001The present disclosure relates to the field of metal-plastic molding, and more specifically to shells, methods of making shells, and electronic products with shells.

0002As consumption levels rise, electronic products with a special texture are very competitive in the market. The metal shell can provide excellent visual effects while having advantages such as delicate feel, wear resistance, drop resistance and corrosion resistance.

<p num="0003"><patcit num="1"><text>U.S. Patent Application Publication No. 2011/0297549</text></patcit></p>

<p num="0004"> Existing methods of making shells with metal and plastic generally use adhesives to bond the metal and plastic together. However, the obtained mobile phone shell does not have wear resistance and drop resistance, and the bonding force between metal and plastic is poor. In addition, the adhesive has poor acid resistance and alkali resistance, and the obtained mobile phone shell cannot be surface-treated such as anodizing.</p><p num="0005"> The embodiments of the present disclosure seek to some extent solve at least one of the existing problems in the prior art. The present disclosure also provides a shell capable of having a strong bonding force between a metal and a plastic and having advantages such as wear resistance, drop resistance and corrosion resistance, and a method for producing the shell. I am aiming.</p>

<p num="0006"> According to the first aspect of the present disclosure, an oxide formed between a metal shell body, a plastic part formed of a resin, and the metal shell body and the plastic part to join the plastic part to the metal shell body. The oxide layer is provided with a physical layer, and the oxide layer has corrosive pores having an average pore diameter of about 200 nm to about 2000 nm on the surface in contact with the plastic part, and the pore diameter is about about 200 nm on the surface in contact with the metal shell body. Provided is a shell having micropores of 10 to 100 nm, characterized in that a part of the resin is filled in the micropores and the corroded pores.</p><p num="0007"> According to the second aspect of the present disclosure, there is provided a method of making the shell, which may be used to make the shell described above. According to the embodiment of the present disclosure, the method is obtained in S1: a step of anodizing at least a part of the surface of the metal shell to form an oxide layer having micropores, S2: the step S1. A step of immersing the obtained metal shell body in an etching solution to form corrosion holes in at least a part of the outer surface of the oxide layer, and S3: a resin in at least a part of the metal shell body obtained in the step S2. May have a step of injecting to obtain the shell in which the resin is molded into a plastic part.</p><p num="0008"> According to a third aspect of the present disclosure, an electronic product with the shell described above is provided.</p><p num="0009"> Surprisingly, we have discovered that a unique two-layer spatial pore structure can be formed in the oxide layer formed on the surface of the metal shell. By the method according to the embodiment of the present disclosure, the oxide layer can be formed on the surface of the metal shell body, and the oxide layer can have micropores having excellent properties. According to the technical solution according to the embodiment of the present disclosure, micropores having an average pore diameter of about 10 to 100 nm can be formed, which is a unique structure and has an excellent bonding force with a resin. .. On the other hand, by further corrosion treatment, corrosion holes may be formed on the outer surface of the oxide layer so as to come into contact with the resin. Corroded pores can have an average pore diameter larger than the micropores. According to the technical solution according to the embodiment of the present disclosure, the average pore size is about 200 nm to about 2000 nm.<u style="single">Corrosion hole</u>However, it can be formed on the outer surface of the oxide layer, which is a unique structure that contributes to enhance the bonding force of the resin with the metal shell body, so that the obtained shell is wear resistant and It can have drop resistance performance. In the course of subsequent molding steps, the resin may penetrate the pores of the inner layer through relatively larger pores on the outer surface of the metal shell, which makes molding easier. According to the embodiments of the present disclosure, the metal shell body is tightly bonded to the plastic without additional portions to provide higher strength and thus improved corrosion resistance. According to the embodiments of the present disclosure, there is little effect on the size and appearance of the metal shell, and only relatively little heat is generated during the process. On the other hand, the resin can be easily injection-molded into a corroded hole having a larger hole diameter on the surface, and there is no special requirement for the resin. Therefore, this technical solution can be widely used, environmentally friendly and can be adopted for mass production.</p><p num="0010"> Further aspects and advantages of the embodiments of the present disclosure are described to some extent in the following description, which will be apparent to some extent from the following description, or will be learned from the implementation of the embodiments of the present disclosure.</p><p num="0011"> These and other aspects and advantages of the present disclosure, along with the drawings, will become apparent from the following description and will be more easily understood from the following description.</p>

0012<figref num="1">It is a figure which shows the existence of the two-layer space pore structure of the oxide layer produced by one Embodiment of this disclosure.</figref><figref num="2">It is a scanning electron microscope inspection figure which shows the aluminum alloy thin plate surface obtained after the surface treatment 1 in Example 1. FIG.</figref><figref num="3a">It is a scanning electron microscope inspection figure which shows the aluminum alloy thin plate surface obtained after the surface treatment 2 in Example 1. FIG.</figref><figref num="3b">It is a scanning electron microscope inspection figure which shows the aluminum alloy thin plate surface obtained after the surface treatment 3 in Example 1. FIG.</figref><figref num="4">It is the schematic which shows the metal shell body of the mobile phone shell which concerns on one Embodiment of this disclosure.</figref><figref num="5">It is the schematic which shows the plastic part of the mobile phone shell which concerns on one Embodiment of this disclosure.</figref><figref num="6">It is the schematic which shows the mobile phone shell which concerns on one Embodiment of this disclosure.</figref>

0013Embodiments of the present disclosure will be described in detail. The embodiments described herein are for illustration and illustration purposes only and are used to gain a general understanding of the present disclosure. This embodiment should not be construed as limiting this disclosure.

0014According to the first aspect of the present disclosure, a shell is provided. According to the embodiments of the present disclosure, the shell may include a plastic part, a metal shell body, and an oxide layer formed between the metal shell body and the plastic parts. According to the embodiments of the present disclosure, the plastic part may be formed of a resin, and the oxide layer may join the plastic part to a metal shell body. According to the embodiment of the present disclosure, the oxide layer has corrosion pores having an average pore diameter of about 200 nm to about 2000 nm on the surface in contact with the plastic part, and the pore diameter is about 10 on the surface in contact with the metal shell body. It has micropores of ~ 100 nm. Further, according to the embodiment of the present disclosure, a part of the resin is filled in the micropores and the corroded pores. Therefore, the bonding force between the metal shell body and the plastic is enhanced and becomes stronger, and the shell can have wear resistance, drop resistance and corrosion resistance.

0015According to the embodiments of the present disclosure, the average pore diameter of the corroded pores is about 200 nm to about 1000 nm, preferably about 400 nm to about 1000 nm, and the average pore diameter of the micropores is about 20 nm to about 80 nm. It may be preferably about 20 nm to about 60 nm. Therefore, the pore structure of the two layers may be further optimized, further contributes to the direct injection of the resin during molding, and improves the bond of the resin with the metal thin plate body.

0016According to the embodiments of the present disclosure, the average of corroded holes<u style="single">Depth</u>May be about 0.5 μm to about 9.5 μm, preferably 0.5 μm to 5 μm. Therefore, the structure of the corroded pores may be further optimized, which contributes to the penetration of the injected resin.

0017According to the embodiments of the present disclosure, the corroded pores may communicate with the micropores. Therefore, the two-layer pore structure may be further optimized, which further contributes to the direct injection and molding of the resin and improves the binding of the resin to the metal thin plate.

0018According to the embodiments of the present disclosure, the thickness of the oxide layer may be from about 1 μm to about 10 μm, preferably from about 1 μm to about 5 μm. Therefore, the bond of the oxide layer with the aluminum alloy body is improved, and the oxide layer further optimizes the structure of the corrosion pores, and thus facilitates the generation of the optimized corrosion pores.

0019According to the embodiments of the present disclosure, the average depth of the micropores may be from about 0.5 μm to about 9.5 μm, preferably from about 0.5 μm to about 5 μm. Therefore, the structure of the micropores may be further optimized, thus improving the filling degree of the molten resin in the micropores, ensuring the penetration of the resin into the micropores of such depth, and the resin and oxidation. The bonding region between the objects is reduced, there are no gaps in the micropores, and the bonding force is further enhanced.

0020According to embodiments of the present disclosure, the type of plastic part is not particularly limited as long as it can be formed from a resin, and the plastic part can be used as any part of the shell.

0021According to an embodiment of the present disclosure, referring to FIG. 5, the plastic part may have a plastic shell body 2 having a shape similar to that of a metal shell body, and other parts such as a display screen of a mobile phone or Free space may be defined by the plastic shell 2 to accommodate the antenna. The plastic shell body 2 may be provided at the end of the metal shell body 1, and the oxide layer is formed between the end of the plastic shell body 2 and the metal shell body 1, and the oxide layer is formed. The plastic shell body 2 may be joined to the end of the metal shell body 1. According to embodiments of the present disclosure, the plastic shell 2 may be provided at one end or two ends of the metal shell body 1, depending on certain desirable needs. According to the embodiments of the present disclosure, the plastic shell body 2 may be adapted to the metal shell body 1, that is, the plastic shell body 2 may form the entire shell shape together with the metal shell 1. According to the embodiment of the present disclosure, the plastic shell body 2 is joined to one end of the metal shell body 1, and the oxide layer is formed on the metal shell body 1 and the plastic shell body 2. It may be provided between them, so that the plastic shell body 2 may be joined to the metal shell body 1 via an oxide layer formed from the metal oxide. According to the embodiments of the present disclosure, a part of the resin forming the plastic shell body may be filled in the micropores and the corroded holes, and as a result, the plastic shell body and the metal shell body are integrally bonded. .. According to the embodiments of the present disclosure, the size of the surface for joining the plastic shell body to the metal shell body is not limited. In one embodiment of the present disclosure, the width of the surface joining the plastic shell and the metal shell is relatively small, from about 0.5 mm to about 2 mm, and therefore a stronger binding force is required.

0022According to embodiments of the present disclosure, the plastic component may further have reinforcing ribs 51 made of resin, which may extend along the inner surface of the metal shell body of the metal shell body. It is joined to the inner surface. According to the embodiment of the present disclosure, the oxide layer may be formed between the reinforcing ribs and the inner surface of the metal shell body, and the resin forming the reinforcing ribs may be formed on the corrosion holes of the oxide layer and the corrosion holes of the oxide layer.<u style="single">Micropores</u>May be filled in. Therefore, the bonding force between the plastic shell body and the metal shell body is further enhanced, and therefore the drop resistance of the obtained shell can be enhanced.

0023According to the embodiments of the present disclosure, the plastic component may have a plastic patch 3 provided on the inner surface of the metal shell body 1, and the plastic patch 3 is joined to the inner surface of the metal shell body 1. According to the embodiments of the present disclosure, the oxide layer is formed between the plastic patch 3 and the inner surface of the metal shell body 1, and the plastic patch 3 may be joined to the inner surface of the metal shell body 1. Plastic patch 3 The resin forming the above is filled in the micropores and corroded pores of the oxide layer. According to the embodiments of the present disclosure, the shape and size of the plastic patch are not particularly limited, and for example, the plastic patch may be used as a support for the antenna. Further, in order to reduce the space, the plastic patch may be in the shape of a thin plate, is arranged on the inner surface of the metal shell body, adheres to the surface of the metal shell body, and is in contact with the surface. Plastic patches may be used to attach the WIFI antenna. Therefore, in order to avoid metal shielding of signal communication, an opening for signal communication is provided on the surface where the plastic patch is joined to the metal shell body. The size and shape of the opening are not particularly limited in the present disclosure, and for example, the opening may be a small slit provided so that a part of the plastic patch is exposed.

0024According to the embodiments of the present disclosure, the plastic component may have a plastic support provided on the inner surface of the metal shell body, and the plastic support is joined to the inner surface of the metal shell body. According to the embodiments of the present disclosure, the oxide layer is formed between the plastic support and the inner surface of the metal shell body, and the plastic support is joined to the inner surface of the metal shell body. According to the embodiment of the present disclosure, the resin forming the plastic support is filled in the micropores and the corroded pores of the oxide layer. The structure and function of the plastic support formed from the resin may be designed according to the desired needs. According to the embodiments of the present disclosure, the plastic support has a mounting portion and a mounting hole. In one embodiment of the present disclosure, the mounting holes may be screw holes. According to embodiments of the present disclosure, the plastic support may be used to accommodate other components, such as cell phone components, and to securely mount components within the space of the shell, and therefore. It provides robust mounting, wear resistance, drop resistance, beautiful appearance and ease of assembly performance.

0025According to the embodiments of the present disclosure, the plastic component has a plastic substrate provided at the end of the metal shell body. According to the embodiments of the present disclosure, the plastic substrate is perpendicular to the metal shell body, and the edge portion of the plastic substrate is joined to the inner surface or the end portion of the metal shell body. According to the embodiments of the present disclosure, the oxide layer is formed between the plastic substrate and the inner surface or the end portion of the metal shell body, and the plastic substrate is joined to the inner surface or the end portion of the metal shell body. .. According to the embodiment of the present disclosure, the resin forming the plastic substrate is filled in the micropores and the corroded pores of the oxide layer. According to embodiments of the present disclosure, plastic substrates may be used to mount GPRS, Bluetooth® and infrared antennas.

0026According to embodiments of the present disclosure, the plastic component may have at least one of the plastic shells, plastic supports and plastic patches described above for mounting the antenna as desired. .. The assembly of the antenna is not particularly limited, and those skilled in the art may simply attach the thin plate antenna to the plastic component, or may form the antenna by chemical plating.

0027According to the embodiments of the present disclosure, the plastic component has a plastic shell body, a plastic support, a plastic patch provided on the plastic support, and a plastic substrate. According to the embodiment of the present disclosure, the plastic shell body is connected to the plastic substrate via the plastic support, and the plastic shell, the plastic support, the plastic patch and the plastic substrate are integrally formed.

0028According to the second aspect of the present disclosure, a method for producing the above-mentioned aluminum alloy is provided. This method S1: A step of anodizing at least a part of the surface of a metal shell to form an oxide layer having micropores. Have.

0029According to embodiments of the present disclosure, in this step, at least a portion of the surface of the metal shell body pretreated prior to step S1 may optionally be anodized, thus providing an oxide layer. , It may be formed on a part of the surface of the aluminum alloy, or the oxide layer may be formed with micropores. According to embodiments of the present disclosure, methods of anodizing are well known to those of skill in the art. According to embodiments of the present disclosure, step S1, ie, anodizing, optionally comprises a portion of the surface of the pretreated metal shell before this step, having a concentration of from about 10% to about 30% by weight. H which is%₂SO₄Placed as an anode in the solution, a part of the surface of the metal shell is electrolyzed at a temperature of about 10 ° C to about 30 ° C for about 1 minute to about 40 minutes at a voltage of about 10 V to about 100 V to increase the thickness. It may have to form an oxide layer of about 1 μm to about 10 μm. According to embodiments of the present disclosure, any device well known for anodizing may be applied to the present disclosure, eg, according to embodiments of the present disclosure, anodizing tanks may be applied. Good. According to the embodiments of the present disclosure, the preferred thickness of the oxide layer formed by the anodizing treatment may be from about 1 μm to about 10 μm, preferably from about 1 μm to about 5 μm. According to the embodiments of the present disclosure, the average pore size of the micropores of the oxide layer may be about 10 nm to about 100 nm, preferably about 20 nm to about 80 nm, and more preferably about 20 nm. It may be ~ about 60 nm. According to the embodiments of the present disclosure, the depth of the micropores may be from about 0.5 μm to about 9.5 μm, preferably from 0.5 μm to about 5 μm. Surprisingly, we have found that the micropores provide a stronger bond between the oxide layer and the resin.

0030According to embodiments of the present disclosure, the portion of the surface of the metal shell to be anodized may be any portion to be joined to the plastic part. According to the embodiments of the present disclosure, the plastic part has a plastic shell body, and a part of the surface of the metal shell body to be anodized is at least a part of the end portion of the metal shell body. There may be. According to the embodiments of the present disclosure, the plastic part has a plastic support, and a part of the surface of the metal shell body to be anodized is at least a part of the inner surface of the metal shell body. You may. According to the embodiments of the present disclosure, the plastic part has a plastic patch, and a part of the surface of the metal shell body to be anodized is at least a part of the inner surface of the metal shell body. May be good. According to the embodiments of the present disclosure, the plastic component has a plastic substrate, and a part of the surface of the metal shell body to be anodized is at least a part of the inner surface or the end portion of the metal shell body. And the surface around it. According to one embodiment of the present disclosure, the entire metal shell body may be anodized to form an oxide layer on the surface of the metal shell body, and the formed oxide layer has an average pore size. It may have micropores of about 10 nm to about 100 nm. It should be noted that the formed micropores can be easily removed, for example by polishing, and do not adversely affect the appearance of the resulting shell.

0031S2: A step of immersing the metal shell body obtained in step S1 in an etching solution to form corrosion holes in at least a part of the outer surface of the oxide layer.

0032According to the embodiment of the present disclosure, in this step, the metal shell body obtained in step S1 may be immersed in the etching solution, so that the corroded pores having a pore diameter of about 200 nm to about 2000 nm are formed in the step. It may be formed on the outer surface of the oxide layer formed on the aluminum alloy substrate in S1.

0033In this step, the etching solution is used to process the aluminum alloy substrate obtained in step S1, so that corrosion pores may be formed on the outer surface of the oxide layer, and the size of the corrosion pores is very small. Usually larger than the size of the hole. As long as the etching solution is a solution that is corrosive to the oxide layer, the type and concentration of the etching solution are not particularly limited. According to the embodiments of the present disclosure, the etching solution is an acid / alkaline etching solution having a pH of about 10 to about 13. According to the embodiments of the present disclosure, the etching solution may be an alkaline solution of a single alkali having a pH of about 10 to about 13 or a mixture of a plurality of alkalis. According to the embodiments of the present disclosure, the etching solution is Na.₂CO₃, LVDS₃, NaOH, NaH₂PO₄, Na₂HPO₄, Na₃PO₄, Na₂SO₃Or Na₂B₄O₇You may have an aqueous solution containing at least one selected from the group consisting of. According to the embodiments of the present disclosure, the alkaline solution is Na₂CO₃And / or LVDS₃It is an aqueous solution containing. According to the embodiments of the present disclosure, in an alkaline solution, Na₂CO₃And / or LVDS₃The weight percent concentration of each is about 0.1% to 15% by weight. According to the embodiments of the present disclosure, in an alkaline solution, Na₂CO₃And / or LVDS₃The weight percent concentration of each is about 0.1 Weight% to 10% by weight. According to the embodiments of the present disclosure, the etching solution may be a mixture of a soluble alkali and a soluble hydrophosphate or dihydrogen phosphate. According to the embodiments of the present disclosure, the soluble alkali may be a strong alkali. According to the embodiments of the present disclosure, the dihydrogen phosphate is at least one selected from the group consisting of sodium dihydrogen phosphate, potassium dihydrogen phosphate, ammonium dihydrogen phosphate and aluminum dihydrogen phosphate. Yes, the soluble alkali is at least one selected from the group consisting of sodium hydroxide and potassium hydroxide. Therefore, the corroded pores formed by the preferable combination of the dihydrogen phosphate and the alkali have a constant pore diameter and are uniformly dispersed on the surface of the oxide layer, so that an excellent pore structure can be formed. Allows for stronger bonding strength performance with aluminum alloy substrates, resulting in higher tensile strength and better integral bonding of aluminum alloy-resin composites. According to the embodiments of the present disclosure, the concentration of dihydrogen phosphate is from about 50% by weight to about 99% by weight, and the concentration of soluble alkali is from about 1% by weight to about 50% by weight, more preferably. The concentration of dihydrogen phosphate is about 60% by weight to about 99% by weight, and the concentration of soluble alkali is about 1% by weight to about 40% by weight. Furthermore, the etching solutions include ammonia solution, hydrazine aqueous solution, hydrazine derivative aqueous solution, water-soluble amine compound aqueous solution, and NH.₃-NH₄It may be at least one of Cl aqueous solutions and the like. According to the embodiment of the present disclosure, the step S2 repeatedly immerses the aluminum alloy obtained in the step S1 in an alkaline solution having a pH of about 10 to about 13 multiple times, that is, twice or more, for example, about 2 to 10 times. It may have a dipping step, each dipping step may last from about 1 minute to about 60 minutes, and step S2 is a cleaning step of cleaning the aluminum alloy with water after each dipping step, eg, deionization. It may further have a step of washing the aluminum alloy with water. According to the embodiments of the present disclosure, the cleaning step may include simply placing the portion to be cleaned in the washing tank and leaving it for about 1 to 5 minutes, and the portion to be cleaned. May have to be washed in a washing tank for about 1 to 5 minutes.

0034S3: A process of injecting resin into at least a part of the metal shell body obtained in step S2 to obtain a shell in which the resin is molded into a plastic part.

0035According to the embodiment of the present disclosure, in this step, the metal shell body obtained after the treatments of steps S1 and S2 may be placed in a mold, and the resin composition is injected into the mold and bonded to the metal shell body. In this way, the shell is made after the molding process.

0036According to the embodiments of the present disclosure, the shell obtained after injection molding may be further annealed at a temperature of about 50 ° C to about 200 ° C. According to the embodiments of the present disclosure, the annealing treatment maintains the shell obtained after injection molding at a temperature of about 50 ° C to about 200 ° C for about 1 to 2 hours, and then lowers the temperature. You may have. For example, the resulting shell may be maintained at about 70 ° C to 180 ° C for about 1 to 1.5 hours, after which the temperature may be lowered. The annealing device may be any device well known to those skilled in the art. For example, the obtained shell may be maintained in a thermostatic electric dryer, or a multi-stage heating furnace may be adopted. According to embodiments of the present disclosure, the resulting shell may be placed directly on the annealing device at temperatures from about 50 ° C to about 200 ° C, or from about 50 ° C to about 200 ° C. Temperatures of ° C may be reached gradually, for example at a rate of 1-10 ° C / min. The temperature may drop to room temperature, eg 15-28 ° C, and may reach such temperatures spontaneously or gradually, eg at a rate of about 1-10 ° C / min, 3-8 °. C / min is preferred. Therefore, the solid resin may be transformed into a liquid phase and permeate into the micropores, and in this way, the bonding force between the metal shell body and the plastic component is further enhanced.

0037As mentioned above, the metal shell may be pretreated prior to the treatment in step S1 and the pretreatment may be mechanical vanishing or mechanical wrapping to surface visible foreign matter. It generally comprises removing from the metal shell and degreasing and cleaning the metal shell to remove process oil adhering to the metal surface. Preferably, the pretreatment is to apply a vanishing finish to the surface of the metal shell body, for example, using sandpaper of about 100 mesh to about 400 mesh or using a grinding machine to give a vanishing finish to the surface of the metal shell body. It has to be applied to form small pores of micron. According to the embodiments of the present disclosure, oil drainage, first washing with water, alkaline etching, second washing with water, neutralization, and water are used in a metal shell body having a vanish finish. Perform the third cleaning in sequence may be. According to embodiments of the present disclosure, the metal shell is approximately 0.5 by sonication with any well known solvent. It may be cleaned for about 2 hours to remove oily stains from the surface of the metal shell body, and then the metal shell body may be placed in an acid / alkaline aqueous solution and the surface of the metal shell body may be cleaned again by sonication. .. The type of solvent and acid / alkali aqueous solution is not limited, the solvent used may be ethanol or acetone, and the acid / alkali aqueous solution may be hydrochloric acid, sulfuric acid, sodium hydroxide, potassium hydroxide, etc. It may be at least one selected from the group consisting of. According to the embodiment of the present disclosure, an oil draining treatment using absolute ethanol is applied to the metal shell body to remove oil from the surface of the metal shell body, and then the metal shell body is washed with water. Then, the washed metal shell is immersed in a sodium hydroxide solution having a concentration of about 30 to 70 g / L at a temperature of about 40 ° C to about 80 ° C, and the aluminum alloy is subjected to alkaline etching for about 1 to 5 minutes. Apply and wash with deionized water. Then 10-30% by weight HNO₃Neutralize the metal shell with, remove trace amounts of alkaline solution, and wash with deionized water. Therefore, pores having a pore diameter of micron may be formed on the surface of the metal shell body. According to the embodiments of the present disclosure, the pore diameter may be about 1 to 10 μm.

0038The metal shell body used in the present disclosure is not particularly limited, and as an example, the metal shell body may be an industry standard 1000 to 7000 series aluminum alloy, or various molded metal shell bodies. The metal shell body in the present disclosure may be a commonly used metal shell body having various shapes and structures, and is not limited in the present disclosure. Various shapes and structures of metal shells may be achieved by mechanical processing.

0039According to the embodiments of the present disclosure, the resin used in the present disclosure may be prepared by mixing a main resin and a polyolefin resin. For example, the resin is prepared by uniformly mixing the main resin and the polyolefin resin and then granulating them using a twin-screw extruder. According to the embodiment of the present disclosure, the fluidity improver and the filler may be added to the main resin and mixed uniformly, and the resin thus obtained has a linear expansion coefficient similar to that of the aluminum alloy. It has both horizontal and vertical directions.

0040According to the embodiments of the present disclosure, the conditions for performing injection molding are not limited. For example, according to one embodiment of the present disclosure, the injection molding conditions are a molding temperature of 50 to 300 ° C, a nozzle temperature of 200 to 450 ° C, a pressure retention time of 1 to 50 seconds, and an injection of 50 to 300 MPa. It may be pressure, injection time of 1-30 seconds, delay time of 1-30 seconds and cooling time of 1-60 seconds. According to one embodiment of the present disclosure, the conditions for injection molding are: molding temperature of 80-200 ° C, nozzle temperature of 200-350 ° C, pressure retention time of 1-10 seconds, injection pressure of 90-140 MPa. It may have an injection time of 3-10 seconds, a delay time of 15-30 seconds and a cooling time of 15-25 seconds. Therefore, the surface of the produced complex may have a resin layer having a depth of 0.5 to 10 mm.

0041The fabrication method of the present disclosure is simple, significantly simplifying the manufacturing process compared to existing adhesive techniques, shortening the corrosion time compared to existing amine materials, and thus shortening the manufacturing process to reduce process complexity. It is significantly reduced. All of the above can only be achieved by performing injection molding directly after using the processing methods of the present disclosure. At the same time, the composite of the aluminum alloy and the resin produced by the production method of the present disclosure has a bonding force between the resin layer and the aluminum alloy substrate, and has a higher tensile shear strength.

0042The resin used in the present invention is not particularly limited, and the resin may be any resin that can be bonded to an aluminum alloy, and a thermoplastic resin is preferable. According to the embodiments of the present disclosure, the thermoplastic resin is a mixture of a main resin and a polyolefin resin. According to the embodiments of the present disclosure, the main resin may be a non-crystalline resin used as an injection molding material, which has both surface gloss and toughness superior to those of the highly crystalline resin in the prior art. Further, polyolefin resins having a melting point of about 65 ° C to about 105 ° C are used. Therefore, injection molding at a specific molding temperature may not be required during molding, subsequent annealing treatment may not be required, the molding process may be simplified, and the obtained metal-resin composite may be obtained. The body structure may reliably have high mechanical strength and excellent surface treatment properties, thus solving the problem of surface decoration of plastic parts and meeting the various requirements of the customer.

0043According to the embodiments of the present disclosure, in the present disclosure, nanoscale micropores on the surface of a thin metal plate are used by using a polyolefin resin having a melting point of about 65 ° C to about 105 ° C as the non-crystalline main resin. Through many experiments, the fluidity of the resin to the resin may be increased, thus ensuring a strong bond between the metal and the plastic and a high mechanical strength of the metal-resin composite structure. Found by the present inventors. Preferably, based on 100 parts by weight of the thermoplastic resin, the amount of the main resin is from about 70 parts by weight to about 95 parts by weight and the amount of the polyolefin resin is from about 5 parts by weight to about 30 parts by weight.

0044Further, the fluidity of the resin may be enhanced by using a fluidity improver in the thermoplastic resin, and thus the adhesive force between the metal and the plastic and the injection molding performance of the resin may be further enhanced. Found by the present inventors. Based on 100 parts by weight of the thermoplastic resin, the thermoplastic resin preferably further contains about 1 part by weight to about 5 parts by weight of the fluidity improver. The fluidity improver is preferably cyclic polycarbonate.

0045As described above, the resin used in the present disclosure may be a non-crystalline resin. According to the embodiments of the present disclosure, the main resin is a mixture of polyphenylene ether (PPO) and polyphenylene sulfide (PPS). According to one embodiment of the present disclosure, in the main resin, the weight ratio of polyphenylene ether to polyphenylene sulfide is about 3: 1 to about 1: 3, preferably about 2: 1 to about 1: 1. According to the embodiments of the present disclosure, the main resin is a mixture of polyphenylene oxide and polyamide. According to one embodiment of the present disclosure, in the main resin, the weight ratio of polyphenylene oxide to polyamide is about 3: 1 to about 1: 3, preferably about 2: 1 to about 1: 1. According to the embodiment of the present disclosure, in the main resin, the main resin is polycarbonate, and the polycarbonate may be straight chain polycarbonate or branched polycarbonate.

0046According to the embodiments of the present disclosure, the melting point of the polyolefin resin is from about 65 ° C to about 105 ° C, and preferably the polyolefin resin may be graft polyethylene. Preferably, graft polyethylene having a melting point of about 100 ° C to about 105 ° C may be used as the polyolefin resin.

0047The resin used in the present disclosure may further contain other modifying additives, and the modifying additives are not particularly limited. For example, the resin may contain a filler. The filler is not particularly limited, and as a non-limiting example, the filler is a fibrous filler or a powder filler. The fibrous filler may be at least one selected from the group consisting of fiberglass, carbon fibers and aromatic polyamide fibers. Further, the powder filler may be at least one selected from the group consisting of calcium carbonate, magnesium carbonate, silica, barium sulfate, talcum powder car, glass and clay. According to the embodiments of the present disclosure, the fibrous filler content is 50 to 150 parts by weight and the powder filler content is 50 to 150 parts by weight, based on 100 parts by weight of the main resin. Therefore, the resin has a coefficient of linear expansion similar to that of an aluminum alloy in both the horizontal direction and the vertical direction.

0048According to the embodiments of the present disclosure, the resin used in the present disclosure may be prepared by mixing a main resin and a polyolefin resin. For example, the resin is prepared by uniformly mixing the main resin and the polyolefin resin and then granulating them using a twin-screw extruder. According to the embodiment of the present disclosure, the fluidity improver and the filler may be added to the main resin and mixed uniformly, and the resin thus obtained has a linear expansion coefficient similar to that of the metal shell body. In both the horizontal and vertical directions.

0049According to the embodiments of the present disclosure, the conditions for performing injection molding are not limited. For example, according to one embodiment of the present disclosure, the injection molding conditions are a molding temperature of 50 to 300 ° C, a nozzle temperature of 200 to 450 ° C, a pressure retention time of 1 to 50 seconds, and an injection of 50 to 300 MPa. It may be pressure, injection time of 1-30 seconds, delay time of 1-30 seconds and cooling time of 1-60 seconds. According to one embodiment of the present disclosure, the conditions for injection molding are: molding temperature of 80-200 ° C, nozzle temperature of 200-350 ° C, pressure retention time of 1-10 seconds, injection pressure of 90-140 MPa. It may have an injection time of 3-10 seconds, a delay time of 15-30 seconds and a cooling time of 15-25 seconds. Therefore, the surface of the produced shell may have a resin layer having a depth of 0.5 to 10 mm.

0050The fabrication method of the present disclosure is simple, significantly simplifying the manufacturing process compared to existing adhesive techniques, shortening the corrosion time compared to existing amine materials, and thus reducing the manufacturing time to reduce process complexity. It is significantly reduced. All of the above may only be achieved by performing injection molding directly after using the processing methods of the present disclosure. At the same time, the shell produced by the production method of the present disclosure has a stronger bonding force between the resin layer and the metal shell body, and has a higher tensile shear strength.

0051The resin used in the present invention is not particularly limited, and the resin may contain any resin that can be bonded to the metal shell body, and a thermoplastic resin is preferable. According to the embodiments of the present disclosure, the thermoplastic resin contains a mixture of a main resin and a polyolefin resin. According to the embodiments of the present disclosure, the main resin has both surface gloss and toughness superior to those of the highly crystalline resin in the prior art, and may contain a non-crystalline resin used as an injection molding material. Often, polyolefin resins having a melting point of about 65 ° C to about 105 ° C are further used. Therefore, injection molding at a specific molding temperature may not be required during molding, subsequent annealing treatment may not be required, the molding process may be simplified, and the obtained metal-resin composite may be obtained. The body structure may reliably have high mechanical strength and excellent surface treatment properties, thus solving the problem of surface decoration of plastic parts and meeting the various requirements of the customer.

0052According to the embodiments of the present disclosure, in the present disclosure, a polyolefin resin having a melting point of about 65 ° C to about 105 ° C is used as the non-crystalline main resin to form a resin for micropores on the surface of a thin metal plate. In this way, strong adhesion between metal and plastic and high mechanical strength of the metal-resin composite structure can be ensured by the present inventor through many experiments. Found by et al. Based on 100 parts by weight of the thermoplastic resin, the amount of the main resin is preferably from about 70 parts by weight to about 95 parts by weight, and the amount of the polyolefin resin is preferably from about 5 parts by weight to about 30 parts by weight.

0053Furthermore, by using a fluidity improver for the thermoplastic resin, the fluidity of the resin may be enhanced, and the adhesive force between the metal and the plastic and the performance of injection molding the resin can be further enhanced. Found by the inventors. Based on 100 parts by weight of the thermoplastic resin, the thermoplastic resin preferably further contains about 1 part by weight to about 5 parts by weight of the fluidity improver. The fluidity improver is preferably cyclic polycarbonate.

0054As described above, the resin used in the present disclosure may be a non-crystalline resin. According to the embodiments of the present disclosure, the main resin is a mixture of polyphenylene ether (PPO) and polyphenylene sulfide (PPS). According to one embodiment of the present disclosure, in the main resin, the weight ratio of polyphenylene ether to polyphenylene sulfide is about 3: 1 to about 1: 3, preferably about 2: 1 to about 1: 1. According to the embodiments of the present disclosure, the main resin is a mixture of polyphenylene oxide and polyamide. According to one embodiment of the present disclosure, in the main resin, the weight ratio of polyphenylene oxide to polyamide is about 3: 1 to about 1: 3, preferably about 2: 1 to about 1: 1. According to the embodiment of the present disclosure, in the main resin, the main resin is polycarbonate, and the polycarbonate may be straight chain polycarbonate or branched polycarbonate.

0055According to the embodiments of the present disclosure, the melting point of the polyolefin resin is from about 65 ° C to about 105 ° C, and the polyolefin resin may preferably contain graft polyethylene. Preferably, graft polyethylene having a melting point of about 100 ° C to about 105 ° C may be used as the polyolefin resin.

0056The resin used in the present disclosure may further contain other modifying additives, and the modifying additives are not particularly limited. For example, the resin may contain a filler. The filler is not particularly limited, and as a non-limiting example, the filler is a fibrous filler or a powder filler. The fibrous filler may be at least one selected from the group consisting of fiberglass, carbon fibers and aromatic polyamide fibers. Further, the powder filler may be at least one selected from the group consisting of calcium carbonate, magnesium carbonate, silica, barium sulfate, talcum powder, glass and clay. According to the embodiments of the present disclosure, the fibrous filler content is 50 to 150 parts by weight and the powder filler content is 50 to 150 parts by weight, based on 100 parts by weight of the main resin. Therefore, the resin has a coefficient of linear expansion similar to that of the metal shell body in both the horizontal direction and the vertical direction.

0057According to the embodiments of the present disclosure, the shell obtained after injection molding may be further subjected to a finishing treatment. For example, the resulting shell may be surface vanished and blasted to remove burrs and make the shell shine to improve aesthetics. The vanishing process may be performed using sandpaper of about 100 mesh to about 400 mesh or using a grinding machine. Blast polishing may be performed using about 100 to about 600 mesh ceramic beads or iron beads to form the sandy appearance of the shell.

0058According to embodiments of the present disclosure, after surface vanishing and blast polishing, the resulting shell is anodized to provide decorative effects of various colors and improve corrosion and wear resistance properties. And dyed surface treatment may be applied. Other surface decoration treatments may be further applied to the shell surface, such as spraying, electrophoresis, PVD, plating, and the like.

0059According to a third aspect of the present disclosure, an electronic product with the shell described above is provided. Examples of electronic products may include mobile phones, PDAs, computers and the like.

0060To further clarify the technical problems, technical solutions and beneficial effects of the present disclosure, the present disclosure will be further described below with reference to the embodiments of the present disclosure. It should be recognized that the particular examples described herein are merely used to understand the present disclosure. This example shall not be construed to limit this disclosure. All the raw materials used in this example and the comparative example are commercially available without particular limitation.

0061Example 1 1. Pretreatment A commercially available A5052 aluminum alloy shell with a thickness of 1 mm is cut into multiple 15 mm x 80 mm rectangular shells (as shown in Figure 4), then ground with a grind and anhydrous ethanol. It was cleaned with, and then immersed in 40 g / L aqueous NaOH solution. After 2 minutes, the rectangular shell was washed with water and dried to give a pretreated aluminum alloy shell.

00622. Surface treatment 1 Each aluminum alloy shell as an anode has 20% by weight H₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy shell was electrolyzed at 18 ° C. for 10 minutes at a voltage of 20 V, after which the aluminum alloy shell was blow dried.

0063The cross section of the aluminum alloy shell obtained after surface treatment 1 was observed with a metallurgical microscope, and it was found that an aluminum oxide layer having a thickness of 5 μm was formed on the surface of the electrolyzed aluminum alloy shell. The surface of the aluminum alloy shell obtained after surface treatment 1 was observed with an electron microscope (see FIG. 2), and micropores having an average pore diameter of about 40 nm to about 60 nm and a depth of 1 μm were formed in the aluminum oxide layer. It turned out that.

00643. Surface treatment 2 10% by weight Na₂CO₃A 500 ml aqueous solution containing (pH = 12.2) was prepared in the beaker. Process (2)<u style="single">(Surface treatment 1)</u>The aluminum alloy lamella obtained after was soaked in sodium carbonate solution at 20 ° C., taken out after 5 minutes, placed in a beaker containing water and soaked for 1 minute. After 5 cycles, after the final soaking in water, the aluminum alloy shell was blow dried.

0065The surface of the aluminum alloy shell obtained after surface treatment 2 was observed with an electron microscope (see FIGS. 3a and 3b), and corroded pores having an average pore diameter of 300 nm to 1000 nm and a depth of 4 μm were immersed. It was found that it was formed on the surface of the aluminum alloy shell. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores.

00664. Molding The dried aluminum alloy shell was inserted into an injection mold with the pattern shown in FIG. A resin composition containing a polyphenylene sulfide (PPS) resin and 30% by weight fiberglass was injection molded. A mobile phone shell, in which a composite of aluminum alloy and resin was tightly bonded, as shown in FIG. 6, was obtained after being removed from the mold and cooled.

0067As shown in FIG. 5, the formed plastic part has a plastic shell body 2, a plastic patch 3, a plastic support 4, and a plastic substrate 5, which are integrally formed. The plastic shell body 2 is provided at one end of the aluminum alloy shell 1, the plastic shell body 2 is very compatible with the aluminum alloy shell 1, and the interface between the plastic shell body 2 and the end of the aluminum alloy shell 1 is the first. The bonding surface 22 of 1 is formed, and the bonding force between the aluminum alloy shell 1 and the plastic shell body 2 is formed by the first bonding surface 22. The plastic substrate 5 is provided at the other end of the aluminum alloy shell 1, is perpendicular to the aluminum alloy shell 1, and the second bonding surface 52 is formed by the interface between the plastic substrate 5 and the aluminum alloy shell 1. The bonding force between the aluminum alloy shell 1 and the plastic substrate is formed by the second bonding surface 52. Aluminum alloy shell 1 from plastic substrate 5 Reinforcing ribs 51 extending along the inner surface of the aluminum alloy shell 1 are formed, and the reinforcing ribs 51 are joined to the inner surface of the aluminum alloy shell 1 which enhances the bonding force between the plastic part and the metal shell body. The plastic shell body 2 is connected to the plastic substrate 5 via a plastic support 4 provided on the inner surface of the metal shell body 1. The plastic support 4 has a framework structure, and the support rod 42 is provided in the middle of the framework, and a plurality of screw holes are formed in the support rod 42. The support rod 42 is the aluminum alloy shell body 1. It is joined to the middle region of the inner surface. The plastic support 4 is perpendicular to the plastic substrate 5, and a framework 44 having a mounting portion 43 is joined to the edge of the metal shell body 1.<u style="single">Plastic support</u>Four The screw hole 41 and the mounting portion 43 arranged in the mobile phone are used for mounting a plurality of parts in the mobile phone. The plastic patch 3 is provided on the plastic support 4, is perpendicular to the support rod 42, forms a cross with the support rod 42, and the end of the plastic patch 3 further engages the framework 44. May be combined. An opening 11 is formed on the outer surface of the shell, below the surface of the plastic patch 3, exposing part of the plastic patch 3 and avoiding metal shielding (see Figure 4). The plastic shell body 2, the plastic patch 3, the plastic support 4, and the plastic substrate are integrally formed by injection molding. Reinforcing ribs 21 extend from the inner surface of the plastic shell body 2, and the reinforcing ribs 21 are joined to the metal shell body 1 to enhance the bonding force between the plastic parts and the aluminum shell body. The plastic shell 2 may be used to mount multiple components such as antennas, display screens, the plastic patch 3 may be used to mount the WIFI antenna, and the plastic substrate 5 May be used to attach antennas for GPRS, Bluetooth® and infrared.

00685. Surface vanishing finish and blast polishing The shell obtained after injection molding was sanded on the surface with 400 mesh sandpaper and blasted with 500 mesh ceramic beads.

00696. Anodizing The resulting shell is 20% by weight H₂SO₄Placed as an anodic in an anodizing tank containing the solution, the shell was electrolyzed at 20 ° C for 140 minutes at a voltage of 20 V and then stained after washing.

0070Example 2 In this example, a shell for a mobile phone was made by substantially the same method as in Example 1 with the following exceptions.

0071In the process of surface treatment 1, each aluminum alloy shell body as an anode has 20% by weight of H.₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy was electrolyzed at 18 ° C. for 10 minutes at a voltage of 15 V, after which the aluminum alloy shell was blow dried.

0072It was observed that a layer of aluminum oxide film having a thickness of about 5 μm was formed after electrolysis, and micropores having a pore size of 20 to 40 nm were formed in the aluminum oxide layer. After surface treatment 2, it was observed that corroded pores having a pore diameter of 300 to 1000 nm and a depth of 4 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0073Example 3 In this example, a shell for a mobile phone was made by substantially the same method as in Example 1 with the following exceptions.

0074In the process of surface treatment 1, each aluminum alloy shell body as an anode has 20% by weight of H.₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy was electrolyzed at 18 ° C for 10 minutes at a voltage of 40 V, after which the aluminum alloy shell was blow dried.

0075It was observed that a layer of aluminum oxide film having a thickness of about 5 μm was formed after electrolysis, and micropores having a pore diameter of 60 to 80 nm and a depth of 1 μm were formed in the aluminum oxide layer. After surface treatment 2, it was observed that corroded pores having a pore diameter of 300 to 1000 nm and a depth of 4 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0076Example 4 In this example, a shell for a mobile phone was made by substantially the same method as in Example 1 with the following exceptions.

0077In the process of surface treatment 1, each aluminum alloy shell body as an anode has 20% by weight of H.₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy was electrolyzed at 18 ° C for 15 minutes at a voltage of 20 V, after which the aluminum alloy shell was blow dried.

0078It was observed that a layer of aluminum oxide film having a thickness of about 7 μm was formed after electrolysis, and micropores having a pore diameter of 40 to 60 nm and a depth of 3 μm were formed in the aluminum oxide layer. After surface treatment 2, it was observed that corroded pores having a pore diameter of 300 to 1000 nm and a depth of 4 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0079Example 5 In this example, a shell for a mobile phone was made by substantially the same method as in Example 1 with the following exceptions.

0080In the process of surface treatment 1, each aluminum alloy shell body as an anode has 20% by weight of H.₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy was electrolyzed at 18 ° C for 15 minutes at a voltage of 15 V, after which the aluminum alloy shell was blow dried.

0081It was observed that a layer of aluminum oxide film having a thickness of about 7 μm was formed after electrolysis, and micropores having a pore diameter of 20 to 40 nm and a depth of 3 μm were formed in the aluminum oxide layer. After surface treatment 2, it was observed that corroded pores having a pore diameter of 300 to 1000 nm and a depth of 4 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0082Example 6 In this example, a shell for a mobile phone was made by substantially the same method as in Example 1 with the following exceptions.

0083In the process of surface treatment 1, each aluminum alloy shell body as an anode has 20% by weight of H.₂SO₄Placed in an anodized tank containing the solution, the aluminum alloy was electrolyzed at 18 ° C for 15 minutes at a voltage of 40 V, after which the aluminum alloy shell was blow dried.

0084It was observed that a layer of aluminum oxide film having a thickness of about 7 μm was formed after electrolysis, and micropores having a pore diameter of 60 to 80 nm and a depth of 3 μm were formed in the aluminum oxide layer. After surface treatment 2, it was observed that corroded pores having a pore diameter of 300 to 1000 nm and a depth of 4 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0085Example 7 In this example, a shell for a mobile phone was made by substantially the same method as in Example 2 with the following exceptions.

0086pH is 11.9 and 5% by weight Na₂CO₃A 100 ml aqueous solution containing the above was prepared in a beaker. Process (2)<u style="single">(Surface treatment 1)</u>The aluminum alloy shell obtained after the above was immersed in a sodium carbonate solution, taken out after 5 minutes, placed in a beaker containing water, and immersed for 1 minute. After 5 cycles, after the final soaking in water, the aluminum alloy shell was blow dried.

0087It was observed that a layer of aluminum oxide film with a thickness of about 5 μm was formed after electrolysis, and micropores with a pore size of 20-40 nm and a depth of 3 μm were formed in the aluminum oxide layer. .. After surface treatment 2, it was observed that corroded pores with a pore diameter of 300 to 600 nm and a depth of 2 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0088Example 8 In this example, a shell for a mobile phone was made by substantially the same method as in Example 2 with the following exceptions.

0089pH 10 and 15% by weight LVDS₃A 100 ml aqueous solution containing the above was prepared in a beaker. Process (2)<u style="single">(Surface treatment 1)</u>The aluminum alloy shell obtained after the above was immersed in a sodium carbonate solution, taken out after 5 minutes, placed in a beaker containing water, and immersed for 1 minute. After 5 cycles, after the final soaking in water, the aluminum alloy shell was blow dried.

0090It was observed that a layer of aluminum oxide film with a thickness of about 5 μm was formed after electrolysis, and micropores with a pore size of 20-40 nm and a depth of 3 μm were formed in the aluminum oxide layer. .. After surface treatment 2, it was observed that corroded pores with a pore diameter of 300 to 600 nm and a depth of 2 μm were formed on the surface of the immersed aluminum alloy thin plate. It may be further observed that a two-layer, three-dimensional pore structure similar to the structure shown in FIG. 1 exists in the aluminum oxide layer, and the corroded pores communicate with the micropores. In this way, a shell for a mobile phone was created.

0091Comparative example 1 1. Pretreatment A commercially available A5052 aluminum alloy shell with a thickness of 1 mm is cut into multiple 15 mm x 80 mm rectangular shells, then grinded and cleaned with absolute ethanol, followed by 2% by weight. It was immersed in an aqueous NaOH solution. After 2 minutes, the rectangular lamella was washed with water and dried to give a pretreated aluminum alloy lamella.

00922. Adhesion A 3M hot melt adhesive was applied to the joint surface between the metal and plastic parts and the two parts were joined by hot pressing.

0093performance test Regarding the bonding force between the aluminum alloy and the resin, the shells for mobile phones produced in Examples 1 to 8 and Comparative Example 1 were fixed to a general material tester, and a tensile test was performed. The test results under maximum load can be regarded as the value of the bonding force between the aluminum alloy and the resin, and the test results are summarized in Table 1.

0094<tables num="1"><img id="000002" he="68" wi="159" file="JP5933765B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

0095It can be seen from Table 1 that the bonding force between the resin and the metal shell body in the shell of the present disclosure can reach up to 1211N, and therefore the bonding is excellent. On the other hand, the bonding force between the resin of the existing shell and the metal shell body is only tens or hundreds of Newtons. The performance of the shells of the present disclosure has been significantly improved as compared to existing shells, making resin molding even easier. The metal shells of the present disclosure do not require additional parts to bond tightly to the resin with higher strength and have little effect on the size of the metal substrate and the appearance of the aluminum alloy. At the same time, it is easier to inject the molding resin directly into the corroded holes with larger surfaces. Also, synthetic resins have no specific requirements and are therefore more versatile. Moreover, there is no environmental pollution, which is more suitable for mass production.

0096Although descriptive embodiments have been shown and stated, it will be appreciated by those skilled in the art that the above embodiments cannot be construed as limiting this disclosure, and any changes, substitutions and adjustments may be made in the spirit, nature and nature of this disclosure. It can be done in this embodiment without departing from the scope.

0097This application claims the priority and gain of Chinese Patent Application No. 201210043628.0, which was filed with the China National Intellectual Property Office on February 24, 2012, and the entire contents of this application can be referred to. Incorporated into the specification.