Preparation method of metallized film on surface of thin-wall special-shaped plastic device

Abstract

The invention relates to a preparation method of a metallized film on the surface of a thin-wall special-shaped plastic device, and relates to the technical field of plastic surface metallization. The method comprises the following steps: S10, activating the surface of a plastic substrate to prepare an ion activation layer; s20, a metal film layer is formed on the side, away from the plastic substrate, of the ion activation layer through evaporation, and the metal film layer comprises a metal bonding layer and a conductive metal layer which are sequentially stacked; wherein first evaporation is adopted for forming the metal bonding layer, and the first evaporation time is 1-3 min; the step of forming the conductive metal layer is at least one time of second evaporation, and the duration of single second evaporation is 3-6 min; the time interval of any two adjacent times of second evaporation is 3-20 min; the time interval between the first evaporation and the first second evaporation is 5-30 min; and S30, a protective film layer is formed on the side, away from the plastic base body, of the metal film layer. The thin-wall plastic metallized device obtained by the preparation method provided by the invention is high in size precision, and the metallized film is firmly combined with the plastic substrate.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic surface metallization, and in particular to a method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device. Background Art

[0002] Engineering plastics have the advantages of light weight, high strength and good stability in space environment, and have broad application prospects in the mechanical electronics industry and aerospace field. Surface metallization of engineering plastics can further meet the functional requirements of metal-like waveguides, electromagnetic shielding and thermal control in the electronics industry, automobile industry and aerospace products, while giving the products a better appearance.

[0003] The types of products in the electronics industry and aerospace are numerous. In order to meet the demand for lightweighting, it is necessary to further reduce the weight of non-standard parts with complex structures, so that the wall thickness of plastic workpieces is less than 1mm, which puts higher requirements on the metallization of plastic products. For example, plastic metallization products used in high-frequency antenna arrays require tens of micron-level error control and hundreds of micron-level flatness requirements. When performing surface metallization on thin-walled special-shaped plastic parts, maintaining high precision and low deformation requirements of plastic products is a technical difficulty in the field of plastic metallization industry.

[0004] At present, the metallization of commercial plastic products is mainly achieved through electroplating, chemical plating, spraying conductive slurry and physical vapor deposition (PVD) technology. When electroplating is used on non-standard parts with complex structures, there will be leakage and uneven film thickness. Chemical plating is often used as a pre-treatment process for electroplating. Its coating is dense and widely applicable to plastic substrates. The disadvantages are short plating solution life and slow coating speed. Both electroplating and chemical plating have serious environmental pollution problems. PVD is an environmentally friendly advanced coating technology that can deposit coatings with a thickness of nanometers to several microns, thereby maintaining the high precision requirements of plastic special-shaped parts (dimensional tolerance 0.02~0.10mm). PVD technology includes three categories: evaporation plating, sputtering plating and ion plating. Among them, sputtering plating and evaporation plating are widely used plastic metallization processes. Compared with sputtering plating, vacuum evaporation equipment and operating costs are relatively low, suitable for large-scale production, and the coating process is relatively simple, and the equipment operation is more convenient.

[0005] When using vacuum evaporation to prepare metal films, it is usually necessary to apply a primer on the plastic substrate to enhance the bonding strength of the metal film, and apply a topcoat on the surface of the metal film as a protective film. This preparation route has complicated procedures. The introduction of the paint film will affect the dimensional accuracy of special-shaped plastic parts on the one hand, and on the other hand, it cannot ensure the uniform coating of the complex surfaces of the special-shaped parts. In addition, when surface metallization is performed on high-temperature resistant engineering plastics such as PEEK, PPS, and LCP, the use of primers is difficult to meet the use conditions of high-temperature environments.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0007] The purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art and provide a method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device, so as to provide a metallized thin-walled special-shaped plastic device with high dimensional accuracy requirements.

[0008] According to one aspect of the present disclosure, a method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device is provided, comprising the following steps:

[0009] S10, obtaining a plastic substrate, and activating the surface of the plastic substrate to prepare an ion activation layer;

[0010] S20, forming a metal film layer by evaporation on a side of the ion activation layer away from the plastic substrate, wherein the metal film layer comprises a metal bonding layer and a conductive metal layer stacked in sequence;

[0011] The metal bonding layer is formed by first evaporation, the first evaporation time is 1 to 3 minutes, and the first evaporation rate is

[0012] The conductive metal layer is formed by performing at least one second evaporation, the duration of a single second evaporation is 3 to 6 minutes, and the rate of a single second evaporation is

[0013] The time interval between any two adjacent second evaporation depositions is 3 to 20 minutes; the time interval between the first evaporation deposition and the first second evaporation deposition is 5 to 30 minutes;

[0014] S30, forming a protective film layer on the side of the metal film layer away from the plastic substrate.

[0015] In an exemplary embodiment of the present disclosure, in step S20, the evaporated film material used to form the metal bonding layer includes at least one of nickel and chromium;

[0016] The thickness of the formed metal bonding layer is 50-200 nm.

[0017] In an exemplary embodiment of the present disclosure, in step S20, the vapor-deposited film material used to form the conductive metal layer includes at least one of silver and copper;

[0018] The thickness of the formed conductive metal layer is 200 nm to 8 μm.

[0019] In an exemplary embodiment of the present disclosure, in step S20, the forming of the metal film layer further comprises forming a metal anchor layer on a side of the conductive metal layer away from the plastic substrate;

[0020] The metal anchor layer is formed by performing at least one third evaporation, the duration of a single third evaporation is 3 to 6 minutes, and the rate of a single third evaporation is

[0021] The time interval between any two adjacent third evaporation depositions is 3 to 20 minutes; the time interval between the second evaporation deposition and the first third evaporation deposition is 3 to 20 minutes.

[0022] In an exemplary embodiment of the present disclosure, in step S20, the forming of the metal anchor layer includes forming a copper metal layer and / or forming a stainless steel layer; the thickness of the copper metal layer is 20 to 100 nm, and the thickness of the stainless steel layer is 200 nm to 500 nm;

[0023] The material of the stainless steel layer is at least one of stainless steel 201, stainless steel 304, stainless steel 310S, stainless steel 316L, and stainless steel 2205.

[0024] In an exemplary embodiment of the present disclosure, in step S10, the preparation of the ion activation layer includes:

[0025] Placing the plastic substrate in a vacuum chamber of a vacuum evaporation machine;

[0026] The vacuum degree of the vacuum chamber is adjusted to ≤0.1Pa, argon and oxygen are introduced, the vacuum degree is maintained at 0.5-10Pa, the oxygen flow rate is set to 20-500sccm, the argon flow rate is set to 0-500sccm, and the power is set to 1000-5000W; the activation treatment is performed for 2-30min, and the temperature in the vacuum chamber is 15-70°C; and an ion activation layer is obtained.

[0027] In an exemplary embodiment of the present disclosure, in step S10, the plastic matrix is ​​any one of polar plastic and non-polar plastic.

[0028] In an exemplary embodiment of the present disclosure, in step S30, the forming of the protective film layer includes forming a metal passivation film layer and forming a closed film layer or an anti-fingerprint film layer on a side of the metal passivation film layer away from the plastic substrate;

[0029] The thickness of the formed protective film layer is 100nm-2μm.

[0030] In an exemplary embodiment of the present disclosure, the pH of the passivation solution used to form the metal passivation film layer is 3-7, the pH of the sealing solution used to form the sealing film layer is 8-11, and the pH of the anti-fingerprint liquid used to form the anti-fingerprint film layer is 8-10.

[0031] In an exemplary embodiment of the present disclosure, the thickness of the formed metal bonding layer is 50 to 200 nm;

[0032] The thickness of the formed conductive metal layer is 200nm to 8μm;

[0033] The thickness of the formed copper metal layer is 20-100 nm, and the thickness of the formed stainless steel layer is 200 nm-500 nm;

[0034] The thickness of the protective film layer formed is 100nm to 2μm;

[0035] The thickness of the metallized film on the surface of the plastic substrate is not greater than 8 μm.

[0036] The method for preparing the metallized film on the surface of a thin-walled special-shaped plastic device provided by the present disclosure forms an ion activation layer on the surface of a plastic substrate by omitting the primer process, thereby greatly reducing the overall thickness of the metallized film, simplifying the metallized film preparation process, and improving the dimensional precision of the thin-walled special-shaped plastic device after surface metallization. In addition, by performing multiple evaporation depositions of the metal film layer at intervals, the influence of evaporation heat radiation on the plastic substrate is reduced, thermal deformation of the thin-walled special-shaped plastic device during the vacuum coating process is avoided, and the uniformity of the coating is improved. The ion activation layer cooperates with the metallized film to further improve the bonding strength between the thin-walled special-shaped plastic device and the metallized film, providing a new option for preparing metallized thin-walled special-shaped plastic devices with high precision requirements.

[0037] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0039] Figure 1 The present invention is a flow chart of a method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device in one embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of the cross-sectional structure of a metallized film in one embodiment of the present disclosure.

[0041] Figure 3 This is a schematic diagram of adhesion test results using the Hundred Grid Method in one embodiment of the present disclosure.

[0042] Figure 4 This is a schematic diagram of the anti-fingerprint effect of the metallized film in one embodiment of the present disclosure.

[0043] Figure 5 This is a diagram showing the anti-fingerprint effect of a thin-walled special-shaped plastic device without a protective film layer in one embodiment of the present disclosure.

[0044] The reference numerals are as follows:

[0045] 1. Plastic matrix, 2. Ion activation layer, 3. Metal bonding layer, 4. Conductive metal layer, 5. Metal anchoring layer, 6. Protective film layer. DETAILED DESCRIPTION

[0046] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0047] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusion and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0048] The term "first evaporation, second evaporation and third evaporation" does not limit the order and number of evaporation, but is only used as a mark to distinguish the evaporation processes of different film layers. For example, in the present disclosure, the first evaporation is used to form a metal bonding layer, and the process parameters of the first evaporation include a duration of 1 to 3 minutes, a rate of The second evaporation is repeated multiple times to form a conductive metal layer. The process parameters of the second evaporation include a duration of 3 to 6 minutes, a rate of At least one third evaporation is used to form a metal anchor layer. The process parameters of the third evaporation include a duration of 3 to 6 minutes, a rate of wait.

[0049] The present disclosure provides a method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device, such as Figure 1 and Figure 2 As shown, the following steps are included:

[0050] S10, obtaining a plastic substrate 1, and activating the surface of the plastic substrate 1 to prepare an ion activation layer 2.

[0051] S20, forming a metal film layer by evaporation on the side of the ion activation layer 2 away from the plastic substrate 1, wherein the metal film layer comprises a metal bonding layer 3 and a conductive metal layer 4 which are stacked in sequence.

[0052] The metal bonding layer 3 is formed by first evaporation, the first evaporation time is 1 to 3 minutes, and the first evaporation rate is

[0053] The conductive metal layer 4 is formed by performing at least one second evaporation, wherein the duration of a single second evaporation is 3 to 6 minutes, and the rate of a single second evaporation is

[0054] The time interval between any two adjacent second evaporation is 3 to 20 minutes; the time interval between the first evaporation and the first second evaporation is 5 to 30 minutes; the time interval is that after completing one evaporation, the evaporation source is turned off, and after a preset time interval, the evaporation source is turned on again to continue evaporation.

[0055] S30 , forming a protective film layer 6 on the side of the metal film layer away from the plastic substrate 1 .

[0056] In this embodiment, in step S10, by forming an ion activation layer 2 on the surface of the plastic substrate 1, the reduction in the dimensional accuracy of the metallized film caused by the use of a primer is avoided. Based on the structural irregularity of the plastic substrate (thin-walled special-shaped plastic device), the use of an ion activation process is more conducive to improving the uniformity of the plastic device after the metallized film is prepared than by applying a primer. In this way, by ion activation of the surface of the plastic substrate 1, a metal film layer can be directly formed on the surface of the plastic substrate 1, which simplifies the preparation process and also ensures good bonding between the plastic substrate 1 and the metal film layer. The metallized film includes an ion activation layer 2, a metal film layer, and a protective film layer 6 which are sequentially stacked in a direction away from the plastic substrate 1.

[0057] In this embodiment, in step S20, a metal film layer is formed by multiple intervals of evaporation, and the single evaporation time of the metal film layer is strictly controlled (3 to 6 minutes). In this way, the influence of the heat radiation of the evaporation on the plastic substrate 1 can be reduced, and the thermal deformation of the thin-walled special-shaped plastic device during the vacuum coating process can be avoided. The thickness of the metal film layer can also be precisely controlled by controlling the evaporation time, further reducing the dimensional tolerance of the thin-walled special-shaped plastic device with high precision requirements. In particular, a shorter evaporation time (1 to 3 minutes) is used during the first evaporation, and the deposition amount of the first coating is reduced to reduce the heat radiation to the plastic substrate 1. After the bonding layer is evaporated, the evaporation source is turned off for 5 to 30 minutes to avoid thermal deformation of the thin-walled plastic surface.

[0058] The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device provided in the embodiment of the present disclosure improves the tightness of the bonding between the metal film layer and the plastic substrate 1 without applying a primer by ionizing the surface of the plastic substrate 1. When the metal bonding layer 3 and the conductive metal layer 4 are evaporated, the heat radiation to the thin-walled plastic substrate 1 during the vacuum evaporation process is reduced by controlling the single evaporation time and the time interval between two adjacent evaporations, thereby avoiding the deformation of the thin-walled plastic substrate 1, and facilitating the control of the thickness of the metal film layer, thereby improving the dimensional accuracy of the plastic substrate 1 after the metallized film is evaporated.

[0059] In the embodiment of the present disclosure, the process of applying the primer is omitted, the overall thickness of the metallized film on the surface of the plastic substrate 1 is reduced, and the preparation process of the metallized film is simplified. Thus, the preparation method of the metallized film provided by the present disclosure improves the bonding force and dimensional accuracy of the metallized film by simplifying the preparation process and controlling the time parameters of the evaporation, thereby providing a new process option for the surface metallization of thin-walled special-shaped plastic devices.

[0060] In one embodiment of the present disclosure, the plastic substrate 1 used in step S10 is a thin-walled special-shaped plastic device. Before forming the ion activation layer 2, the pretreatment of the thin-walled special-shaped plastic device includes: immersing the thin-walled special-shaped plastic device in a hydrocarbon cleaning agent for ultrasonic cleaning for 10 to 30 minutes, using compressed air to blow dry, and placing the thin-walled special-shaped plastic device in an oven for baking for 0.5 to 3 hours, and setting the temperature to 60 to 80°C. Exemplarily, the thin-walled special-shaped plastic device is obtained by precision injection molding and / or high-precision CNC machining. For example, the shrinkage rate of the material can be reduced by adjusting the composition of the material and the modification of the material, combined with the adjustment of the injection molding parameters, thereby improving the injection molding processing accuracy, so that the tolerance range of the obtained plastic device is 0.02 to 0.05mm). When precision injection molding a planar thin-walled special-shaped plastic device, in order to reduce the warping deformation of the injection molded part, it is necessary to select a low-warping plastic and adopt a deformation pre-compensation method to meet the processing accuracy and low deformation requirements of the thin-walled special-shaped plastic device.

[0061] In one embodiment of the present disclosure, in step S10, the preparation of the ion activation layer 2 includes: placing the target plastic device in a vacuum chamber of a vacuum evaporator. The vacuum degree of the vacuum chamber is adjusted to ≤0.1Pa, argon and oxygen are introduced, the vacuum degree is maintained at 0.5-10Pa, the oxygen flow rate is set to 20-500sccm, the argon flow rate is set to 0-500sccm, and the power is set to 1000-5000W. The activation treatment is performed for 2-30min, the temperature in the vacuum chamber is 15-70°C, and the ion activation layer 2 is obtained. In this way, the plastic substrate 1 is activated by low-temperature vacuum oxygen plasma, so that the method is applicable to plastic substrates 1 of various materials.

[0062] In some embodiments, the plastic matrix 1 can be any one of polar plastics and non-polar plastics. Exemplarily, the material of the plastic matrix 1 can be a composite material of one or more of polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyphenylene oxide (PPO), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate / acrylonitrile-butadiene-styrene (PC / ABS), polyvinyl chloride (PVC), nylon (PA), polymethyl methacrylate (PMMA), polyaryletherketone (PAEK), polyphenylene sulfide (PPS), and liquid crystal polymer (LCP).

[0063] In one embodiment of the present disclosure, in step S20, the vapor-deposited film material used to form the metal bonding layer 3 includes at least one of nickel and chromium; the thickness of the formed metal bonding layer 3 is 50 to 200 nm.

[0064] Exemplarily, the purity of the evaporated film material of the metal bonding layer 3 is ≥99.5%.

[0065] In one example, before forming the metal bonding layer 3, the following steps may be further performed: fixing the plastic substrate 1 after the plasma activation treatment in a vacuum chamber, starting the vacuum system, and setting the vacuum degree of the coating chamber to ≤1×10 -2 Pa, preheat the film material to be evaporated, the preheating temperature is 150~200℃, and the preheating time is 60s. The purpose of preheating is to evaporate the water vapor from the evaporation source and improve the coating quality. -4 ~7×10 -3 Pa, pre-melt the film material to be evaporated, the pre-melting time is set to 10-15s, and the temperature is further raised to the set evaporation temperature, the pre-melting temperature is 600-1500℃, and the evaporation temperature is 900-2000℃.

[0066] In one embodiment of the present disclosure, in step S20, the vapor-deposited film material used to form the conductive metal layer 4 includes at least one of silver and copper; the thickness of the formed conductive metal layer 4 is 200 nm to 8 μm.

[0067] Exemplarily, the purity of the evaporated film material used for the conductive metal layer 4 is ≥99.99%.

[0068] In one embodiment of the present disclosure, in step S20, the forming of the multi-layer metal film further includes forming a metal anchor layer 5 on the side of the conductive metal layer 4 away from the plastic substrate 1. The metal anchor layer 5 is formed by performing at least one third evaporation, the duration of a single third evaporation is 3 to 6 minutes, and the rate of a single third evaporation is The time interval between any two adjacent third evaporation depositions is 3 to 20 minutes; the time interval between the second evaporation deposition and the first third evaporation deposition is 3 to 20 minutes.

[0069] In one embodiment of the present disclosure, in step S20, the forming of the metal anchoring layer 5 includes forming a copper metal layer and / or forming a stainless steel layer; the copper metal layer has a thickness of 20 to 100 nm, and the stainless steel layer has a thickness of 200 to 500 nm. The material of the stainless steel layer is at least one of stainless steel 201, stainless steel 304, stainless steel 310S, stainless steel 316L, and stainless steel 2205.

[0070] For example, when the evaporated film material of the conductive metal layer 4 is copper, the evaporated layer formed by the second evaporation for the last time can be used as the copper metal layer of the metal anchor layer 5 .

[0071] In one example, the purity of the evaporated film material of the copper metal layer is ≥99.99%.

[0072] In one example, in order to increase the uniformity of the coating, multiple evaporation sources can be used in the evaporation process. Especially for large-area thin-walled special-shaped plastic devices, multiple evaporation sources can effectively improve the uniformity of the evaporated film. In addition, the use of multiple evaporation sources also facilitates the automated continuous coating of multiple layers of various types of metal films, improving coating efficiency and reducing costs.

[0073] In one embodiment of the present disclosure, in step S30, the forming of the protective film layer 6 includes forming a metal passivation film layer and forming a closed film layer or an anti-fingerprint film layer on the side of the metal passivation film away from the plastic substrate; the thickness of the formed protective film layer 6 is 100nm~2μm.

[0074] In one example, the protective film layer 6 may be a transparent layer, that is, the material used to prepare the protective film layer 6 is a transparent material. In this way, the metal film layer is protected while retaining the appearance of the metal texture.

[0075] In one embodiment of the present disclosure, in step S30, the pH of the passivation solution used to form the metal passivation film layer is 3-7, the pH of the sealing solution used to form the sealing film layer is 8-11, and the pH of the anti-fingerprint liquid used to form the anti-fingerprint film layer is 8-10. By adjusting the pH values ​​of the passivation solution, the sealing solution and the anti-fingerprint solution, the damage to the metal film layer is reduced and the performance of the corresponding film layer formed is improved. Exemplarily, the pH value of the passivation solution is 3-7, which can better prevent the passivation solution components from damaging the metal film layer. At the same time, avoid the selected passivation solution containing solvent components that react with the plastic matrix or swell the plastic matrix. Preferably, a passivation solution treated in a room temperature environment is used. Exemplarily, a copper passivation solution or a stainless steel passivation solution with a pH of 3-7 is sprayed on the surface of a plastic part coated with a metal film layer for passivation treatment, and the surface is dried after the room temperature passivation treatment.

[0076] In one example, the surface of the metal passivation film layer is treated with a sealing solution having a pH of 8 to 11 for 3 to 5 minutes.

[0077] In another example, a spray gun with a diameter of ≤0.8 mm is used to evenly spray a micro-nano anti-fingerprint liquid with a pH of 8 to 10 on the surface of the metal passivation film layer, and the liquid is naturally air-dried or dried.

[0078] In one embodiment of the present disclosure, the thickness of the metallized film on the surface of the plastic substrate is not more than 12 μm. Exemplarily, the thickness of the formed metal bonding layer 3 is 50 to 200 nm; the thickness of the formed conductive metal layer 4 is 200 nm to 8 μm; the thickness of the formed copper metal layer is 20 to 100 nm, the thickness of the stainless steel layer is 200 nm to 500 nm; the thickness of the formed protective film layer 6 is 100 nm to 2 μm. In this way, by adopting the method for preparing the metallized film on the surface of a thin-walled special-shaped plastic device provided by the present disclosure, the total thickness of the prepared metallized film is not more than 8 μm, which can better meet the high-precision requirements of thin-walled plastic devices.

[0079] The method for preparing the metallized film on the surface of a thin-walled special-shaped plastic device provided by the present disclosure is further described below in conjunction with specific embodiments.

[0080] Example 1

[0081] S10, obtaining a plastic matrix (thin-walled special-shaped plastic device): according to the three-dimensional model of the thin-walled special-shaped plastic device product and the material and dimensional tolerance requirements, a thin-walled special-shaped plastic device is obtained by processing using a high-precision CNC machine tool. In this embodiment, PPS plastic material is selected; the processed PPS workpiece is immersed in a hydrocarbon cleaning agent for ultrasonic cleaning for 15 minutes, blown dry with compressed air, and placed in an 80°C oven for baking for 2 hours.

[0082] The surface of the dried PPS thin-walled special-shaped plastic device is subjected to low-temperature plasma activation treatment: when the vacuum degree of the vacuum chamber is ≤0.1Pa, the medium frequency power supply is turned on, the power is set to 3000W, the oxygen flow rate is 50sccm, the argon flow rate is 200sccm, and the treatment time is 15min.

[0083] S20, place the PPS thin-walled special-shaped plastic device after plasma activation treatment in the coating chamber, and evacuate the vacuum to ≤1×10 -2 Pa, preheat the evaporation source to 150°C for 60 seconds. Continue to evacuate the vacuum chamber until the vacuum degree is ≤5×10 -3 Pa, pre-melt nickel metal film material, pre-melting temperature 1200℃, pre-melting time 10s. Continue to increase the evaporation temperature to 1500℃, and turn off the evaporation source after 3min of evaporation. After an interval of 15min, plate the copper metal film, pre-melt at 950℃ for 10s, then heat up to 1300℃ to plate the copper metal layer, the single plating time is 4min, and continue to plate the copper metal layer after an interval of 15min. After 3 consecutive evaporation, turn off the evaporation source. Pre-melt 304 stainless steel film material and heat up to 1500℃, evaporation time 2min, to obtain a PPS thin-walled special-shaped plastic device with a metal film layer.

[0084] Thus, the metal film layer is sequentially a nickel metal bonding layer, a conductive copper metal layer and a stainless steel layer from the side away from the PPS thin-walled special-shaped plastic device outward, and the total thickness of the prepared metal film layer is 2.5 μm.

[0085] S30, immerse the PPS thin-walled special-shaped plastic device coated with a metal film layer in a weakly acidic stainless steel passivation solution (pH = 4-6) for 15 minutes, rinse and dry, immerse in a stainless steel sealing solution (pH = 8-10) for 3-5 minutes, and dry. The total thickness of the prepared metal passivation film layer and the sealing film layer is ≤ 200nm. The prepared thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 1.

[0086] The adhesion and anti-fingerprint effect of the surface metallized thin-walled special-shaped plastic device 1 are tested. Figure 3 As shown in the figure, the adhesion between the metallized film and the surface of the PPS thin-walled special-shaped plastic device reaches 5B level by using the hundred-grid method test. Figure 4 As shown, the surface metallized thin-walled special-shaped plastic device 1 prepared in this embodiment has a good anti-fingerprint effect.

[0087] Example 2

[0088] S10, obtaining a plastic matrix (thin-walled special-shaped plastic device): according to the three-dimensional model of the thin-walled special-shaped plastic device product and the material and dimensional tolerance requirements, a thin-walled special-shaped plastic device is obtained by processing using a high-precision CNC machine tool. In this embodiment, ABS plastic material is selected; the processed ABS workpiece is immersed in a hydrocarbon cleaning agent for ultrasonic cleaning for 15 minutes, blown dry with compressed air, and placed in a 60°C oven for baking for 2 hours.

[0089] The surface of the dried ABS thin-walled special-shaped plastic device is subjected to low-temperature plasma activation treatment: when the vacuum degree of the vacuum chamber is ≤0.1Pa, the medium frequency power supply is turned on, the power is set to 3000W, the oxygen flow rate is 150sccm, the argon flow rate is 100sccm, and the treatment time is 5 to 20min.

[0090] S20, place the ABS thin-walled special-shaped plastic device after plasma activation treatment in the coating chamber, and evacuate the vacuum to ≤1×10 -2 Pa, preheat the evaporation source to 150°C for 60 seconds. Continue to evacuate the vacuum chamber until the vacuum degree is ≤5×10 -3 Pa, pre-melt nickel metal film material, pre-melting temperature 1200℃, pre-melting time 10s. Continue to increase the evaporation temperature to 1500℃, and turn off the evaporation source after 3min of evaporation. After an interval of 15min, plate the silver-copper metal film, pre-melt the silver-copper alloy film material at 950℃ for 10s, then raise the temperature to 1300℃ to plate the silver-copper metal layer, the single plating time is 4min, and continue to plate the silver-copper metal layer after an interval of 15min. After 3 consecutive evaporation, turn off the evaporation source. Pre-melt the copper film material and raise the temperature to 1300℃, the evaporation time is 2min, and an ABS thin-walled special-shaped plastic device with a metal film layer is obtained.

[0091] Thus, the metal film layer is sequentially composed of a nickel metal bonding layer, a conductive silver-copper metal layer and a copper metal layer along the side away from the ABS thin-walled special-shaped plastic device, and the total thickness of the prepared metal film layer is 2.4 μm.

[0092] S30, place a weakly acidic copper metal passivation solution (pH=2-4) in a spray pot, spray the surface of the ABS thin-walled special-shaped plastic device plated with a metal film layer for 3 minutes, let it stand for 10 minutes, rinse it with water, dry it, spray it with a copper metal sealing solution (pH=8-10) for 3-5 minutes, and dry it. The total thickness of the obtained metal passivation film layer and the sealing film layer is ≤200nm. The prepared thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 2.

[0093] The surface metallized thin-walled special-shaped plastic device 2 has an adhesion and anti-fingerprint effect similar to those of the surface metallized thin-walled special-shaped plastic device 1 .

[0094] Example 3

[0095] S10, obtaining a plastic matrix (thin-walled special-shaped plastic device): according to the three-dimensional model of the thin-walled special-shaped plastic device product and the material and dimensional tolerance requirements, a thin-walled special-shaped plastic device is obtained by processing using a high-precision CNC machine tool. In this embodiment, PC / ABS plastic material is selected; the processed PC / ABS workpiece is immersed in a hydrocarbon cleaning agent for ultrasonic cleaning for 15 minutes, blown dry with compressed air, and placed in a 60°C oven for baking for 2 hours.

[0096] The surface of the dried PC / ABS thin-walled special-shaped plastic device is subjected to low-temperature plasma activation treatment: when the vacuum degree of the vacuum chamber is ≤0.1Pa, the medium frequency power supply is turned on, the power is set to 1000W, the oxygen flow rate is 50sccm, the argon flow rate is 200sccm, and the treatment time is 5 to 20min.

[0097] S20, place the PC / ABS thin-walled special-shaped plastic device after plasma activation treatment in the coating chamber, and evacuate the vacuum to ≤1×10 -2 Pa, preheat the evaporation source to 150°C for 60 seconds. Continue to evacuate the vacuum chamber until the vacuum degree is ≤5×10 -3 Pa, pre-melt nickel metal film material, pre-melting temperature 1200℃, pre-melting time 10s. Continue to increase the evaporation temperature to 1500℃, and turn off the evaporation source after 3min of evaporation. After an interval of 15min, plate the silver metal film, pre-melt the silver film material at 900℃ for 10s, then heat it to 1100℃ to plate the silver metal layer, the single plating time is 4min, and continue to plate the silver metal layer after an interval of 15min. After 3 consecutive evaporation, turn off the evaporation source. Pre-melt the copper film material and heat it to 1300℃, the evaporation time is 2min; after an interval of 10min, pre-melt the 304 stainless steel film material and heat it to 1500℃, the evaporation time is 2min, and a PC / ABS thin-walled special-shaped plastic device with a metal film layer is obtained.

[0098] Thus, the metal film layer is sequentially composed of a nickel metal bonding layer, a conductive silver metal layer, a copper metal layer and a stainless steel layer along the side away from the PC / ABS thin-walled special-shaped plastic device, and the total thickness of the prepared metal film layer is 2.7 μm.

[0099] S30, place a weakly acidic stainless steel passivation liquid (pH = 4-6) in a spray pot, spray the surface of the PC / ABS thin-walled special-shaped plastic device coated with a metal film layer for 3 minutes, let it stand for 30 minutes and then rinse it with water, place a weakly alkaline micro-nano anti-fingerprint liquid in a spray gun with a diameter of 0.5 mm, and evenly spray the surface of the passivated thin-walled special-shaped plastic device. The total thickness of the obtained metal passivation film layer and anti-fingerprint film layer is ≤500nm. The prepared thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 3.

[0100] The surface metallized thin-walled special-shaped plastic device 3 has an adhesion and anti-fingerprint effect similar to those of the surface metallized thin-walled special-shaped plastic device 1 .

[0101] Example 4

[0102] S10, obtain plastic matrix (thin-walled special-shaped plastic device): according to the three-dimensional model of thin-walled special-shaped plastic device products and the material and dimensional tolerance requirements, use high-precision CNC machine tools to process thin-walled special-shaped plastic devices. In this embodiment, LCP plastic material is selected, and the dispersed glass fiber reinforced LCP plastic particles are dried and placed in an injection molding machine. The melting temperature and mold temperature are set, and injection molding is performed to obtain a thin-walled special-shaped plastic workpiece. The processed LCP workpiece is immersed in a hydrocarbon cleaning agent for ultrasonic cleaning for 15 minutes, blown dry with compressed air, and placed in a 90°C oven for baking for 1 hour.

[0103] The surface of the dried LCP thin-walled special-shaped plastic device is subjected to low-temperature plasma activation treatment: when the vacuum degree of the vacuum chamber is ≤0.1Pa, the medium frequency power supply is turned on, the power is set to 1000W, the oxygen flow rate is 50sccm, the argon flow rate is 200sccm, and the treatment time is 20min.

[0104] S20, place the LCP thin-walled special-shaped plastic device after plasma activation treatment in the coating chamber, and evacuate the vacuum to ≤1×10 -2 Pa, preheat the evaporation source to 150°C for 60 seconds. Continue to evacuate the vacuum chamber until the vacuum degree is ≤5×10 -3 Pa, pre-melt the chromium metal film material, the pre-melting temperature is 1400℃, and the pre-melting time is 10s. Continue to increase the evaporation temperature to 1800℃, and turn off the evaporation source after 3min of evaporation. After an interval of 15min, plate the silver metal film, pre-melt the silver film material at 900℃ for 10s, then raise the temperature to 1100℃ to plate the silver metal layer, the single plating time is 4min, and continue to plate the silver metal layer after an interval of 15min. After 3 consecutive evaporation, turn off the evaporation source. Pre-melt the copper film material and raise the temperature to 1300℃, the evaporation time is 2min, and an LCP thin-walled special-shaped plastic device with a metal film layer is obtained.

[0105] Thus, the metal film layer is sequentially composed of a chromium metal bonding layer, a conductive silver metal layer and a copper metal layer along the side away from the LCP thin-walled special-shaped plastic device, and the total thickness of the prepared metal film layer is 2.4 μm.

[0106] S30, place a weakly acidic stainless steel passivation liquid (pH = 4-6) in a spray pot, spray the surface of the LCP thin-walled special-shaped plastic device coated with a metal film layer for 3 minutes, let it stand for 30 minutes and then rinse it with water, place a weakly alkaline micro-nano anti-fingerprint liquid in a spray gun with a diameter of 0.5 mm, and evenly spray the surface of the passivated thin-walled special-shaped plastic device. The total thickness of the obtained metal passivation film layer and anti-fingerprint film layer is ≤500nm. The prepared thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 4.

[0107] The surface metallized thin-walled special-shaped plastic device 4 has an adhesion and anti-fingerprint effect similar to those of the surface metallized thin-walled special-shaped plastic device 1 .

[0108] Example 5

[0109] The difference between this embodiment and embodiment 1 is that the thin-walled special-shaped plastic device is made of PEAK material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 5. The surface metallized thin-walled special-shaped plastic device 5 has an adhesion and anti-fingerprint effect close to that of the surface metallized thin-walled special-shaped plastic device 1.

[0110] Example 6

[0111] The difference between this embodiment and embodiment 1 is that the thin-walled special-shaped plastic device is made of PC material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 6. The surface metallized thin-walled special-shaped plastic device 6 has an adhesion and anti-fingerprint effect close to that of the surface metallized thin-walled special-shaped plastic device 1.

[0112] Example 7

[0113] The difference between this embodiment and embodiment 2 is that the thin-walled special-shaped plastic device is made of PVC material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 7. The surface metallized thin-walled special-shaped plastic device 7 has an adhesion and anti-fingerprint effect close to that of the surface metallized thin-walled special-shaped plastic device 1.

[0114] Example 8

[0115] The difference between this embodiment and embodiment 2 is that the thin-walled special-shaped plastic device is made of PMMA material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 8. The surface metallized thin-walled special-shaped plastic device 8 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0116] Example 9

[0117] The difference between this embodiment and embodiment 3 is that the thin-walled special-shaped plastic device is made of PP material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 9. The surface metallized thin-walled special-shaped plastic device 9 has an adhesion and anti-fingerprint effect close to that of the surface metallized thin-walled special-shaped plastic device 1.

[0118] Example 10

[0119] The difference between this embodiment and embodiment 3 is that the thin-walled special-shaped plastic device is made of PE material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 10. The surface metallized thin-walled special-shaped plastic device 10 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0120] Embodiment 11

[0121] The difference between this embodiment and embodiment 3 is that the thin-walled special-shaped plastic device is made of PS material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 11. The surface metallized thin-walled special-shaped plastic device 11 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0122] Example 12

[0123] The difference between this embodiment and embodiment 3 is that the thin-walled special-shaped plastic device is made of PA material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 12. The surface metallized thin-walled special-shaped plastic device 12 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0124] Example 13

[0125] The difference between this embodiment and embodiment 4 is that the thin-walled special-shaped plastic device is made of PC material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 13. The surface metallized thin-walled special-shaped plastic device 13 has an adhesion and anti-fingerprint effect close to that of the surface metallized thin-walled special-shaped plastic device 1.

[0126] Embodiment 14

[0127] The difference between this embodiment and embodiment 4 is that the thin-walled special-shaped plastic device is made of PPO material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 14. The surface metallized thin-walled special-shaped plastic device 14 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0128] Embodiment 15

[0129] The difference between this embodiment and embodiment 4 is that the thin-walled special-shaped plastic device is made of PBT material; the obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 15. The surface metallized thin-walled special-shaped plastic device 15 has an adhesion and anti-fingerprint effect similar to that of the surface metallized thin-walled special-shaped plastic device 1.

[0130] Comparative Example 1

[0131] S10, obtaining a plastic matrix (thin-walled special-shaped plastic device): according to the three-dimensional model of the thin-walled special-shaped plastic device product and the material and dimensional tolerance requirements, a thin-walled special-shaped plastic device is obtained by processing using a high-precision CNC machine tool. In this embodiment, PPS plastic material is selected, and the processed PPS workpiece is immersed in a hydrocarbon cleaning agent for ultrasonic cleaning for 15 minutes, blown dry with compressed air, and placed in an 80° C. oven for 2 hours.

[0132] The surface of the dried PPS thin-walled special-shaped plastic device is subjected to low-temperature plasma activation treatment: when the vacuum degree of the vacuum chamber is ≤0.1Pa, the medium frequency power supply is turned on, the power is set to 3000W, the oxygen flow rate is 50sccm, the argon flow rate is 200sccm, and the treatment time is 15min.

[0133] S20, place the PPS thin-walled special-shaped plastic device after plasma activation treatment in the coating chamber, and evacuate the vacuum to ≤1×10 -2 Pa, preheat the evaporation source to 150°C for 60 seconds. Continue to evacuate the vacuum chamber until the vacuum degree is ≤5×10 -3 Pa, pre-melt nickel metal film material, pre-melting temperature 1200 ℃, pre-melting time 10s. Continue to increase the evaporation temperature to 1500 ℃, and turn off the evaporation source after 3 minutes of evaporation. After an interval of 15 minutes, plate the copper metal film, pre-melt the copper film material at 950 ℃ for 10 seconds, then raise the temperature to 1300 ℃ to plate the copper metal layer, the single plating time is 4 minutes, and continue to plate the copper metal layer after an interval of 15 minutes. After 3 consecutive evaporation, turn off the evaporation source to obtain a PPS thin-walled special-shaped plastic device with a metal film layer.

[0134] Thus, the metal film layer is sequentially composed of a chromium metal bonding layer and a conductive silver metal layer along the side away from the PPS thin-walled special-shaped plastic device, and the total thickness of the prepared metal film layer is 2.2 μm.

[0135] The obtained thin-walled special-shaped plastic device with a metallized film is defined as a surface metallized thin-walled special-shaped plastic device 16. Figure 5 As shown, the surface metallized thin-walled special-shaped plastic device 16 has no anti-fingerprint effect.

[0136] It should be noted that, although the steps of the method for preparing the metallized film on the surface of a thin-walled special-shaped plastic device in the present disclosure are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired result. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0137] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device, characterized in that: The following steps are involved: S10, obtaining a plastic substrate, and activating the surface of the plastic substrate to prepare an ion activation layer; S20, forming a metal film layer by evaporation on a side of the ion activation layer away from the plastic substrate, wherein the metal film layer comprises a metal bonding layer and a conductive metal layer stacked in sequence; The metal bonding layer is formed by first evaporation, the first evaporation time is 1 to 3 minutes, and the first evaporation rate is The conductive metal layer is formed by performing at least one second evaporation, the duration of a single second evaporation is 3 to 6 minutes, and the rate of a single second evaporation is The time interval between any two adjacent second evaporation depositions is 3 to 20 minutes; the time interval between the first evaporation deposition and the first second evaporation deposition is 5 to 30 minutes; S30, forming a protective film layer on the side of the metal film layer away from the plastic substrate.

2. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 1, characterized in that: In step S20, the evaporated film material used to form the metal bonding layer includes at least one of nickel and chromium; The thickness of the formed metal bonding layer is 50-200 nm.

3. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 1, characterized in that: In step S20, the vapor-deposited film material used to form the conductive metal layer includes at least one of silver and copper; The thickness of the formed conductive metal layer is 200 nm to 8 μm.

4. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to any one of claims 1 to 3, characterized in that: In step S20, the forming of the metal film layer further comprises forming a metal anchor layer on a side of the conductive metal layer away from the plastic substrate; The metal anchor layer is formed by performing at least one third evaporation, the duration of a single third evaporation is 3 to 6 minutes, and the rate of a single third evaporation is The time interval between any two adjacent third evaporation depositions is 3 to 20 minutes; the time interval between the second evaporation deposition and the first third evaporation deposition is 3 to 20 minutes.

5. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 4, characterized in that: In step S20, the forming of the metal anchoring layer includes forming a copper metal layer and / or forming a stainless steel layer; the copper metal layer has a thickness of 20 to 100 nm, and the stainless steel layer has a thickness of 200 nm to 500 nm; The material of the stainless steel layer is at least one of stainless steel 201, stainless steel 304, stainless steel 310S, stainless steel 316L, and stainless steel 2205.

6. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 4, characterized in that: In step S10, the preparation of the ion activation layer includes: Placing the plastic substrate in a vacuum chamber of a vacuum evaporation machine; The vacuum degree of the vacuum chamber is adjusted to ≤0.1Pa, argon and oxygen are introduced, the vacuum degree is maintained at 0.5-10Pa, the oxygen flow rate is set to 20-500sccm, the argon flow rate is set to 0-500sccm, and the power is set to 1000-5000W; the activation treatment is performed for 2-30min, and the temperature in the vacuum chamber is 15-70°C; and an ion activation layer is obtained.

7. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 1, characterized in that: In step S10, the plastic matrix is ​​any one of polar plastic and non-polar plastic.

8. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 4, characterized in that: In step S30, the forming of the protective film layer includes forming a metal passivation film layer and forming a closed film layer or an anti-fingerprint film layer on a side of the metal passivation film layer away from the plastic substrate; The thickness of the formed protective film layer is 100nm-2μm.

9. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 8, characterized in that: The pH of the passivation solution used to form the metal passivation film layer is 3-7, the pH of the sealing solution used to form the sealing film layer is 8-11, and the pH of the anti-fingerprint liquid used to form the anti-fingerprint film layer is 8-10.

10. The method for preparing a metallized film on the surface of a thin-walled special-shaped plastic device according to claim 9, characterized in that: The thickness of the formed metal bonding layer is 50 to 200 nm; The thickness of the formed conductive metal layer is 200nm to 8μm; The thickness of the formed copper metal layer is 20-100 nm, and the thickness of the stainless steel layer is 200 nm-500 nm; The thickness of the protective film layer formed is 100nm to 2μm; The thickness of the metallized film on the surface of the plastic substrate is not greater than 8 μm.

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