Shielding Film for Wireless Charging, Preparation Method Thereof and Manufacturing Equipment

Abstract

The present invention discloses a shielding film for wireless charging, a preparation method thereof, and a manufacturing device. The shielding film for wireless charging includes an adhesive layer and a magnetic layer formed on one surface of the adhesive layer by magnetron sputtering. The magnetic layer is (Fe 65 Co 35 ) x (TiO2) 1‑x layer, where x≥0.76; the saturation magnetic induction intensity B of the magnetic layer s ≥1.7T. Compared with the traditional iron-based nanocrystalline thin strip, the shielding film for wireless charging of the present invention has a higher saturation magnetic induction intensity and resonance frequency, improves the magnetic coupling efficiency of the receiving coil at the wireless charging receiving end, and thus effectively improves the wireless charging power, efficiency and speed.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless charging, and particularly to a shielding film for wireless charging, a preparation method thereof, and a manufacturing device therefor. Background Art

[0002] With the development of wireless charging technology, more and more electronic products are equipped with wireless charging functions. Currently, most wireless charging is achieved by electromagnetic induction coupling. The principle of electromagnetic induction coupling is to realize wireless charging through the coupling of the magnetic fields generated by the transmitting coil and the receiving coil. However, at present, the wireless charging power is small and the charging time is long, which cannot meet the requirements of high-power and high-efficiency wireless charging for electronic products.

[0003] Most of the shielding films used in existing wireless charging receivers are iron-based nanocrystalline thin strips after heat treatment. Their resonance frequency is low (about 10 MHz), which is not suitable for working at higher frequencies. Moreover, the saturation magnetic induction intensity is low, only 1 - 1.3 T, and the electromagnetic induction coupling efficiency is low, resulting in limited electromagnetic induction coupling power. There are disadvantages such as a limited maximum output power and a limited upper limit of the charging speed, and it cannot meet the requirements of high-power and fast wireless charging for electronic products. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a shielding film for wireless charging with a high saturation magnetic induction intensity, a preparation method for preparing the shielding film for wireless charging, and a manufacturing device for manufacturing the shielding film for wireless charging.

[0005] To solve the above technical problem, the first technical solution adopted by the present invention is: a shielding film for wireless charging, including an adhesive layer and a magnetic layer formed on one side surface of the adhesive layer by magnetron sputtering. The magnetic layer is a (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x ≥ 0.76; the saturation magnetic induction intensity B s ≥ 1.7 T.

[0006] To solve the above technical problem, the second technical solution adopted by the present invention is: a preparation method for a shielding film for wireless charging, including the following steps,

[0007] Obtain a single-sided adhesive, the single-sided adhesive including a release film, an adhesive layer, and a protective film stacked in sequence;

[0008] Remove the film, and remove the protective film of the single-sided adhesive;

[0009] Magnetron sputtering is carried out on the surface of the adhesive layer away from the release film to form a magnetic layer on the surface of the adhesive layer away from the release film, thereby obtaining a shielding film for wireless charging. The magnetic layer is (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B of the magnetic layer s ≥1.7T.

[0010] To solve the above technical problems, the third technical solution adopted by the present invention is: a manufacturing device for a shielding film for wireless charging, including a film removal chamber and a magnetron sputtering chamber. A film tearing device is provided in the film removal chamber, and the film tearing device is used to tear off the protective film of the single-sided adhesive; a magnetron sputtering device is provided in the magnetron sputtering chamber, and the magnetron sputtering device is used to magnetron sputter and form a magnetic layer on the surface of the adhesive layer of the single-sided adhesive away from the release film. The magnetic layer is (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B of the magnetic layer s ≥1.7T.

[0011] The beneficial effects of the present invention are as follows:

[0012] This shielding film for wireless charging has a higher saturation magnetic induction intensity and resonance frequency compared with traditional iron-based nanocrystalline thin tapes, improving the magnetic coupling efficiency of the receiving coil of the wireless charging receiver, thereby effectively improving the wireless charging power, efficiency and speed.

[0013] The preparation method of this shielding film for wireless charging only needs one step of magnetron sputtering to deposit a magnetic thin film material [i.e., (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer] on the tape, which is simpler and more time-saving than the traditional preparation method of preparing amorphous thin tapes by rapid quenching and then obtaining nanocrystalline magnetic materials through heat treatment; and subsequent wireless charging preparation processes, such as magnetic fragmentation and lamination, can also be realized through the preparation method of this shielding film for wireless charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 FIG. is a schematic structural diagram of a shielding film for wireless charging according to Embodiment 1 of the present invention;

[0015] Figure 2 FIG. is a hysteresis loop diagram of a shielding film for wireless charging according to Embodiment 1 of the present invention;

[0016] Figure 3 Magnetic spectrum diagram of the shielding film for wireless charging in the first embodiment of the present invention;

[0017] Figure 4 Hysteresis loop diagram of the iron-based nanocrystalline magnetic film for wireless charging in the prior art;

[0018] Figure 5 Magnetic spectrum diagram of the iron-based nanocrystalline magnetic film for wireless charging in the prior art;

[0019] Figure 6 Flow chart of the preparation method of the shielding film for wireless charging in the second embodiment of the present invention;

[0020] Figure 7 Simplified schematic diagram of the manufacturing equipment of the shielding film for wireless charging in the third embodiment of the present invention.

[0021] Label description:

[0022] 1. Adhesive layer;

[0023] 2. Magnetic layer;

[0024] 3. Release film;

[0025] 4. Film removal chamber; 41. Film tearing device;

[0026] 5. Pretreatment chamber; 51. Pretreatment device;

[0027] 6. Magnetron sputtering chamber; 61. Sputtering target; 62. Cooling roller;

[0028] 7. Rewinding chamber; 71. Rewinding device. Detailed implementation manners

[0029] To describe in detail the technical content, achieved objectives and effects of the present invention, the following is described in conjunction with the embodiments and with reference to the accompanying drawings.

[0030] Please refer to Figures 1 to 7 , the shielding film for wireless charging includes an adhesive layer 1 and a magnetic layer 2 formed on one side surface of the adhesive layer 1 by magnetron sputtering. The magnetic layer 2 is a (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B s ≥1.7T.

[0031] As can be seen from the above description, the beneficial effects of the present invention are as follows: This shielding film for wireless charging has a higher saturation magnetic induction intensity and resonance frequency compared with traditional iron-based nanocrystalline ribbons, improving the magnetic coupling efficiency of the receiving coil at the wireless charging receiving end, thereby effectively improving the wireless charging power, efficiency, and speed.

[0032] Further, a release film 3 is provided on the other surface of the adhesive layer 1 opposite to the magnetic layer 2.

[0033] As can be seen from the above description, after the user tears off the release film 3, the adhesive layer 1 having the (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer can be bonded to an external component, greatly facilitating the use of the shielding film for wireless charging and enhancing the user experience. The material of the adhesive layer 1 includes but is not limited to acrylic adhesives, polycarbonate adhesives, etc.

[0034] A method for preparing a shielding film for wireless charging includes the following steps:

[0035] Obtain a single-sided adhesive, which includes a release film, an adhesive layer, and a protective film stacked in sequence;

[0036] Remove the film, and tear off the protective film of the single-sided adhesive;

[0037] Magnetron sputtering: Magnetron sputtering is performed on the surface of the adhesive layer away from the release film to form a magnetic layer on the surface of the adhesive layer away from the release film, thereby obtaining a shielding film for wireless charging. The magnetic layer is a (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B s ≥1.7T.

[0038] As can be seen from the above description, the beneficial effects of the present invention are as follows: The method for preparing this shielding film for wireless charging only requires one step of magnetron sputtering to deposit a magnetic thin film material [i.e., the (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer] on the adhesive tape, which is simpler and more time-saving than the traditional method of preparing an amorphous ribbon by rapid cooling and then obtaining a nanocrystalline magnetic material through heat treatment; and through this method for preparing a shielding film for wireless charging, subsequent wireless charging preparation processes, such as magnetic fragmentation and lamination, can also be achieved.

[0039] Further, a step of pretreatment is also included between the step of film tearing and the step of magnetron sputtering, and the surface of the adhesive layer away from the release film is activated.

[0040] As can be seen from the above description, activating the deposition surface of the adhesive layer increases the surface energy of the adhesive layer, which is beneficial to increasing the adhesion of the deposition surface of the adhesive layer and ensuring the forming effect of the (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer.

[0041] Further, a step of winding is also included after magnetron sputtering, and the wireless charging shielding film is wound.

[0042] As can be seen from the above description, the wound wireless charging shielding film is convenient for storage and transportation.

[0043] Further, the sputtering target 61 used during magnetron sputtering is a composite target of Fe 65 Co 35 and TiO 2 .

[0044] A manufacturing device for a wireless charging shielding film includes a film removal chamber 4 and a magnetron sputtering chamber 6. A film tearing device 41 is provided in the film removal chamber 4, and the film tearing device 41 is used to tear off the protective film of the single-sided adhesive. A magnetron sputtering device is provided in the magnetron sputtering chamber 6, and the magnetron sputtering device is used to magnetron sputter and form a magnetic layer on the surface of the adhesive layer of the single-sided adhesive away from the release film. The magnetic layer is (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B s ≥1.7T.

[0045] Further, a pretreatment chamber 5 is also included between the film removal chamber 4 and the magnetron sputtering chamber 6, and a pretreatment device 51 is provided in the pretreatment chamber 5.

[0046] Further, a winding chamber 7 is also included. The winding chamber 7 is communicated with the output port of the magnetron sputtering chamber 6, and a winding device 71 is provided in the winding chamber 7.

[0047] Further, a sputtering target 61 is provided on the magnetron sputtering device, and the sputtering target 61 is a composite target of Fe 65 Co 35 and TiO 2 .

[0048] Example 1

[0049] Please refer to Figures 1 to 5 . Embodiment 1 of the present invention is: a shielding film for wireless charging, which is applied to the wireless charging receiving end and is particularly suitable for high-frequency working conditions.

[0050] As Figure 1 shown, the shielding film for wireless charging includes an adhesive layer 1 and a magnetic layer 2 formed on one side surface of the adhesive layer 1 by magnetron sputtering. A release film 3 is provided on the other side surface of the adhesive layer 1 opposite to the magnetic layer 2. That is to say, among the two side surfaces of the adhesive layer 1, the magnetic layer 2 is deposited on one side surface, and the release film 3 is provided on the other side surface. When in use, the user can tear off the release film 3 and then fix the magnetic layer 2 on the external component through the adhesive layer 1.

[0051] The magnetic layer 2 is a (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B s of the magnetic layer 2≥1.7T.

[0052] To fully illustrate the advantages of this shielding film for wireless charging, the inventor prepared samples and used the iron-based nanocrystalline magnetic film for wireless charging in the prior art as a control group. Among them, x = 0.78 in the sample, that is, the magnetic layer 2 is a (Fe 65 Co 35 ) 0.78 (TiO 2 ) 0.22 layer. Specifically, Fe 65 Co 35 and TiO 2 patch are used as composite targets and are prepared under the conditions of a sputtering power of 175W and a working gas pressure of 0.17Pa. Its hysteresis loop is as Figure 2 shown. It can be seen from Figure 2 that its saturation magnetic induction intensity is 1.8T, and its magnetic spectrum is as Figure 3 shown. It can be seen from Figure 3 that its resonance frequency is above 3GHz. The iron-based nanocrystalline magnetic film in the control group is prepared from amorphous Fe 74 Nb 3 Si 15.5 B 6.5 Cu 1 ribbons under the vacuum heat treatment conditions of 580°C. Its hysteresis loop is as Figure 4 shown. It can be seen from Figure 4 that its saturation magnetic induction intensity is 1.1T, and its magnetic spectrum is as Figure 5 shown. It can be seen from Figure 5It can be seen that its resonance frequency is around 10 MHz. Thus, it can be seen that the shielding film for wireless charging of the present invention has a higher saturation magnetic induction intensity and resonance frequency compared with the traditional iron-based nanocrystalline thin strip.

[0053] Example Two

[0054] Please refer to Figure 6 , Example Two of the present invention is the preparation method for preparing the shielding film for wireless charging described in Example One, including the following steps,

[0055] Obtain a single-sided adhesive, the single-sided adhesive includes a release film, an adhesive layer and a protective film stacked in sequence; in this embodiment, the width of the single-sided adhesive is 50 mm and the thickness is 80 μm.

[0056] Remove the film, remove the protective film of the single-sided adhesive;

[0057] Magnetron sputtering, magnetron sputtering is performed on the surface of the adhesive layer away from the release film to form a magnetic layer on the surface of the adhesive layer away from the release film, thereby obtaining a shielding film for wireless charging. The magnetic layer is (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; the saturation magnetic induction intensity B s ≥1.7 T. It is easy to understand that in other embodiments, x can also be other values, such as 0.78, 0.8, 0.82, etc.

[0058] To improve the adhesion of the deposition surface of the adhesive layer, a step of pretreatment is also included between the step of removing the film and the step of magnetron sputtering, and the surface of the adhesive layer away from the release film is activated.

[0059] After magnetron sputtering, a step of winding is also included, and the shielding film for wireless charging is wound up.

[0060] It is not difficult to understand that the sputtering target used during magnetron sputtering is Fe 65 Co 35 and TiO 2 composite target. In order for the composition and saturation magnetic induction intensity of the shielding film for wireless charging to meet the preset range, it is necessary to adjust the content of TiO 2 in the composite target. Currently, there are two adjustment methods. One is that when the Fe 65 Co 35 target and the TiO 2 target are independent (that is, when the Fe 65 Co 35 target and the TiO 2 target are sputtered simultaneously), the Fe65 Co 35 Target and TiO 2 Sputtering power of the target; Second, when TiO 2 The sheet is mounted on Fe 65 Co 35 On the target, by increasing or decreasing Fe 65 Co 35 TiO on the target 2 The number of sheets can be adjusted.

[0061] Example 3

[0062] Please refer to Figure 7 Example 3 of the present invention is a manufacturing apparatus for a wireless charging shielding film used in the method for manufacturing a wireless charging shielding film described in Example 2.

[0063] Manufacturing apparatus for a wireless charging shielding film, including a film removal chamber 4, a pretreatment chamber 5, a magnetron sputtering chamber 6, and a winding chamber 7 that are connected in sequence. When manufacturing a wireless charging shielding film, the single-sided adhesive sequentially passes through the film removal chamber 4, the pretreatment chamber 5, the magnetron sputtering chamber 6, and the winding chamber 7. The single-sided adhesive includes a release film, an adhesive layer, and a protective film that are laminated in sequence. The film removal chamber 4, the pretreatment chamber 5, the magnetron sputtering chamber 6, and the winding chamber 7 are respectively vacuum chambers.

[0064] A film tearing device 41 is provided in the film removal chamber. The film tearing device 41 is used to tear off the protective film of the single-sided adhesive.

[0065] A pretreatment device 51 is provided in the pretreatment chamber 5. The pretreatment device 51 is used to activate the surface of the adhesive layer of the single-sided adhesive away from the release film.

[0066] A magnetron sputtering device is provided in the magnetron sputtering chamber 6. A sputtering target 61 is provided on the magnetron sputtering device. The sputtering target 61 is a Fe 65 Co 35 And TiO 2 Composite target. The magnetron sputtering device is used to magnetron sputter and form a magnetic layer on the surface of the adhesive layer of the single-sided adhesive away from the release film. The magnetic layer is a (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer, where x≥0.76; The saturation magnetic induction intensity B of the magnetic layer s≥1.7T. Specifically, the magnetron sputtering device includes a cooling roller 62, and the sputtering target 61 is disposed close to the cooling roller 62. In order to save sputtering time, a plurality of sputtering targets 61 are disposed around the cooling roller 62. Preferably, the number of the sputtering targets 61 is greater than or equal to four (for example, four, five, six, eight, etc.). In this embodiment, Fe 65 Co 35 targets are independent of the TiO 2 targets. By adjusting the power of the Fe 65 Co 35 targets and the TiO 2 targets, the content x of TiO in the magnetic layer can be controlled, for example, x = 0.8. The thickness of the magnetic layer is controlled by adjusting the sputtering gas pressure or the moving speed of the single-sided adhesive. The magnetron sputtering chamber 6 maintains a background vacuum lower than 1×10 2 Pa. -3 Pa.

[0067] The winding chamber 7 communicates with the output port of the magnetron sputtering chamber 6, and a winding device 71 is provided in the winding chamber 7.

[0068] In summary, the wireless charging shielding film, its preparation method and manufacturing equipment provided by the present invention. Compared with the traditional iron-based nanocrystalline thin strip, the wireless charging shielding film of the present invention has a higher saturation magnetic induction intensity and resonance frequency, improves the magnetic coupling efficiency of the receiving coil at the wireless charging receiving end, and thus effectively improves the wireless charging power, efficiency and speed. The preparation method of the wireless charging shielding film of the present invention only needs one step of magnetron sputtering to deposit a magnetic thin film material [i.e., (Fe 65 Co 35 ) x (TiO 2 ) 1-x layer] on the adhesive tape, which is simpler and more time-saving than the traditional preparation method of preparing an amorphous thin strip by rapid quenching and then obtaining a nanocrystalline magnetic material by heat treatment; and the subsequent wireless charging preparation processes, such as magnetic breaking and laminating, can also be realized by the preparation method of the wireless charging shielding film of the present invention.

[0069] The above are only the embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent transformation made by using the specification and drawings of the present invention, or directly or indirectly applied in the relevant technical fields, shall be included in the patent protection scope of the present invention by the same token.

Claims

1. Preparation method of shielding film for wireless charging, Characterized in that, The shielding film for wireless charging comprises an adhesive layer and a magnetic layer formed on one side surface of the adhesive layer by magnetron sputtering. The preparation method comprises the following steps: Obtain a single-sided adhesive, which comprises a release film, an adhesive layer and a protective film laminated in sequence; Film tearing, tear off the protective film of the single-sided adhesive; Magnetron sputtering is used to magnetron sputter on the surface of the adhesive layer away from the release film to form a magnetic layer on the surface of the adhesive layer away from the release film, thereby obtaining a shielding film for wireless charging. The magnetic layer is (Fe 65 Co 35 ). x (TiO 2 ). 1-x layer, where x ≥ 0.76; the saturation magnetic induction intensity Bs of the magnetic layer ≥ 1.7 T.

2. The preparation method of the shielding film for wireless charging according to claim 1, Characterized in that: A release film is provided on the other side surface of the adhesive layer opposite to the magnetic layer.

3. The preparation method of the shielding film for wireless charging according to claim 1, Characterized in that: A pretreatment step is further included between the film tearing step and the magnetron sputtering step, and the side surface of the adhesive layer away from the release film is activated.

4. The preparation method of the shielding film for wireless charging according to claim 1, Characterized in that: After magnetron sputtering, a winding step is further included, and the shielding film for wireless charging is wound.

5. The preparation method of the shielding film for wireless charging according to claim 1, Characterized in that: The sputtering target used during magnetron sputtering is Fe 65 Co 35 and TiO 2 composite target.

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