Matte black functional film and preparation method thereof

Abstract

The invention belongs to the technical field of films, and particularly discloses a matt black functional film and a preparation method thereof.The film comprises a base layer arranged on the surface of a base material, a transition layer is arranged on the base layer, and a blackening functional layer is arranged on the transition layer; wherein the base layer is metal simple substances and carbides thereof, the transition layer is metal carbides and a small amount of carbon simple substances, and the blackening functional layer is metal carbides and a large amount of carbon simple substances. The matt black functional film is prepared by adopting a physical vapor deposition process which can be a magnetron sputtering or multi-arc ion plating process, and after a target material and a base material are etched in sequence, a base coat, a transition layer and a functional layer are prepared on the surfaces of the base material, the base coat and the transition layer respectively. Through cooperation of the base layer, the transition layer and the functional layer, the extinction coefficient of the film is reduced, and the binding force and hardness of the film are improved, so that the film shows uniform and stable matt black in simple special-shaped parts and plane parts, has excellent wear resistance, and can be widely applied to the field of electronic component film coating or decoration film coating.

Description

Technical Field

[0001] The present invention relates to the technical field of thin films, and relates to a matte black functional thin film and a preparation method thereof. Background Art

[0002] Decorative coatings are mainly used to improve the appearance of devices, while enhancing the corrosion resistance or wear resistance of devices and extending their service life. The matte black tone has visual characteristics of being low-key, simple and modern, and has a high light absorption coefficient, which can prevent devices from being denatured due to light exposure, and is used on a certain scale in the field of electronic components or decorations. However, in the process of large-scale industrial applications, matte black decorative plating must meet the following requirements: 1. The decorative coating should have good comprehensive performance. During the use of decorative plated devices, scratches will inevitably occur. If the matte black decorative plating has poor wear resistance, the decorative coating will peel off, shortening the service life of the device. 2. The preparation process should be simple and the yield rate should be high. 3. The cost should be controlled at a low level and it should be easy to carry out large-scale production.

[0003] CN112342512A discloses a blue-black metal thin film, a preparation method and an application thereof. Although this method can improve the quality of the decorative plated thin film, it cannot take into account strong bonding, excellent wear resistance and high extinction coefficient. CN115976466A discloses a black thin film, a preparation method and an application thereof, but it needs to be equipped with a variety of targets to achieve, has high requirements for deposition equipment, and has a high cost. Summary of the Invention

[0004] The present invention provides a matte black functional thin film and a preparation method thereof. The thin film has a high extinction coefficient, high bonding strength and hardness, making the thin film present a uniform and stable matte black color in products of simple shaped parts and flat parts, and having excellent wear resistance.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions: A matte black functional thin film includes a primer layer provided on the surface of a substrate, a transition layer provided on the primer layer, and a blackening functional layer provided on the transition layer; wherein the primer layer is a metal element and its carbide, the transition layer is a metal carbide and a small amount of carbon element, and the blackening functional layer is a metal carbide and a large amount of carbon element.

[0006] Optionally, the metal in the metal element and the metal carbide is Cr or Ti.

[0007] Optionally, the ratio of the mass percentage of the metal element to its carbide in the primer layer is 70-80%:20-30%.

[0008] Optionally, the ratio of the mass percentage of the metal carbide to the carbon element in the transition layer is 70-80%:20-30%.

[0009] Optionally, the ratio of the mass percentage of metal carbide to elemental carbon in the blackening functional layer is 30-40%:60-70%.

[0010] Optionally, the total thickness of the matte black functional film is 2.5 μm - 5.5 μm, wherein the thickness of the underlayer is 0.1μm - 0.5 μm, the thickness of the transition layer is 0.4 μm - 1 μm, and the thickness of the blackening functional layer is 2 μm - 4 μm.

[0011] The present invention also relates to a method for preparing the matte black functional film. The substrate is cleaned and etched, and then an underlayer, a transition layer, and a blackening functional layer are sequentially deposited on the substrate by magnetron sputtering or multi-arc ion plating; the target in the deposition process is a Cr target or a Ti target, and the carbon source reaction gas is CH 4 or C 2 H 2 , and the working gas is Ar.

[0012] Optionally, when preparing by magnetron sputtering process, it includes the following steps: S1. Introduce the carbon source reaction gas and the working gas. The flow rate of the carbon source reaction gas is 50 sccm - 150 sccm, the flow rate of the working gas is 200 sccm - 400 sccm, the bias voltage is 50 V - 100 V, the target current is 10 A - 15 A, and the deposition temperature is 120 - 160 °C, to deposit the underlayer on the substrate; S2. Introduce the carbon source reaction gas and the working gas. The flow rate of the carbon source reaction gas is 50 sccm - 150 sccm, the flow rate of the working gas is 200 sccm - 600 sccm, the bias voltage is 80 V - 120 V, the target current is 6 A - 9 A, and the deposition temperature is 120 - 160 °C, to deposit the transition layer on the underlayer; S3. Introduce the carbon source reaction gas and the working gas. The flow rate of the carbon source reaction gas is 50 sccm - 150 sccm, the flow rate of the working gas is 300 sccm - 600 sccm, the bias voltage is 50 V - 100 V, the target current is 3 A - 5 A, and the deposition temperature is 120 - 160 °C, to deposit the blackening functional layer on the transition layer.

[0013] Optionally, when depositing by multi-arc ion plating process, it specifically includes the following steps: S1. Introduce the carbon source reaction gas and the working gas. The flow rate of the carbon source reaction gas is 200 sccm - 300 sccm, the flow rate of the working gas is 20 sccm - 30 sccm, the bias voltage is 150 V - 200 V, the target current is 70 A - 90 A, and the deposition temperature is 120 - 160 °C, to deposit the underlayer on the substrate; S2, introducing carbon source reaction gas and working gas, the flow rate of carbon source reaction gas is 250 sccm~350 sccm, the flow rate of working gas is 20 sccm~30 sccm, the bias voltage is 100 V~200 V, the target current is 60 A~70 A, the deposition temperature is 120~160°C, and a transition layer is deposited on the base layer; S3. Carbon source reaction gas and working gas are introduced, the flow rate of carbon source reaction gas is 300 sccm~400 sccm, the flow rate of working gas is 20 sccm~30 sccm, the bias voltage is 100 V~150 V, the target current is 50 A~60 A, the deposition temperature is 120~160°C, and a blackening functional layer is deposited on the transition layer.

[0014] The invention also relates to the application of the matte black functional film in the coating of electronic components.

[0015] The present invention has the following beneficial effects: The matte black functional film provided by the present invention comprises a base layer, a transition layer and a blackening functional layer sequentially arranged on a substrate, wherein the base layer is formed by depositing a metal element and its carbide, which can enhance the bonding force between the base layer and the substrate, the transition layer is deposited by mixing metal carbide and a small amount of carbon element, the metal carbide content is higher than the carbon element, so as to improve the wear resistance of the transition layer; the blackening functional layer is deposited by mixing metal carbide and a large amount of carbon element, the metal carbide content is lower than the carbon element, so as to control the functional layer to be matte black. The film has a low extinction coefficient, and the matte black color is uniform and stable, and the film has both strong bonding and high hardness, has good wear resistance, and has a simple structure, and the raw materials are easily available, and the equipment requirements are low, the preparation cost is low, and it is easy to promote and apply.

[0016] The matte black functional film prepared by the present invention is a multi-layer coating system prepared by magnetron sputtering or multi-arc ion plating technology. Metal elements, their carbides, and carbon are designed as coating components, so that the prepared matte black functional film has both a high extinction coefficient, high bonding strength and hardness, uniform and stable matte black color, excellent wear resistance, effectively solving the disadvantage of poor comprehensive performance of traditional matte black functional films. Its blackening functional layer contains a large amount of carbon (in the form of graphite). With its relatively high extinction coefficient (the extinction coefficient of graphite is relatively high, approximately around 1 to 3), a large amount of carbon can absorb and scatter light, which is the key factor to achieve the matte black color and high light absorption performance of the film. As a component in each layer, chromium carbide also plays an auxiliary and supplementary role in the overall extinction effect (the extinction coefficient of chromium carbide is usually between 0.5 and 1.5). Working in cooperation with carbon, they jointly enable the film to have good extinction performance and achieve the matte black appearance effect. The matte black functional film prepared by magnetron sputtering has a uniform and dense film formation, strong bonding force with the substrate, and precise component ratios in each layer. The matte black functional film prepared by multi-arc ion plating is firmly bonded to the substrate by virtue of the high ionization rate of particles, and its mechanical properties are also significantly improved. In addition, the metal in the metal element and metal carbide in the underlayer component is Cr or Ti. Cr and Ti are metal elements with good hardness, wear resistance, and chemical stability, which can provide a solid foundation in the film structure and enhance the adhesion between the film and the substrate. At the same time, the ratio range of the mass percentage of the metal element to its carbide in the underlayer is between 70%:30% and 80%:20%, which helps to provide suitable surface characteristics for the adhesion of the subsequent transition layer while ensuring good bonding with the substrate. The ratio range of the mass percentage of metal carbide and carbon in the transition layer component is between 70%:30% and 80%:20%, making the transition layer have a certain hardness and wear resistance while having an appropriate amount of carbon to improve the interfacial bonding force and wettability, which is beneficial to the deposition of the blackening functional layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 FIG. is a schematic structural diagram of the matte black functional film of the present invention, in which 110 - substrate, 120 - matte black functional film, 121 - underlayer, 122 - transition layer, 123 - blackening functional layer.

[0018] Figure 2 For the embodiments of the present invention 1 Comparison of the appearance of electronic components before and after the deposition of the matte black functional film.

[0019] Figure 3 FIG. shows the appearance of a special-shaped electronic component after the deposition of the matte black functional film in Embodiment 2 of the present invention.

[0020] Figure 4This is the appearance of the electronic component after the matte black film is deposited in Comparative Example 1 of the present invention.

[0021] Figure 5 This is the appearance of the electronic component after the matte film is deposited in Comparative Example 2 of the present invention. DETAILED DESCRIPTION

[0022] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials used in the following examples are commercially available products unless otherwise specified.

[0023] like Figure 1 As shown, the matte black functional film includes a high bonding primer layer 121 disposed on the surface of a substrate 110, a wear-resistant transition layer 122 disposed on the primer layer 121, and a blackening functional layer 123 disposed on the transition layer 122. Specifically, the primer layer is a metal element and its carbide, and the mass percentage ratio of the two is between 70%:30% and 80%:20%, preferably 75%:25%; the thickness of the primer layer is 0.1 μm~0.5 μm, preferably 0.3 μm. The transition layer is a metal carbide and a small amount of carbon, and the mass percentage ratio of the two is between 70%:30% and 80%:20%; preferably 75%:25%; the thickness of the transition layer is 0.4 μm~1 μm; preferably 0.7 μm; the blackening functional layer is a metal carbide and a large amount of carbon, and the mass percentage ratio of the two is between 30%:70% and 40%:60%; preferably 35%:65%; the thickness of the blackening functional layer is 2 μm~4 μm; preferably 3 μm.

[0024] The present invention also relates to a method for preparing the matte black functional film, wherein the substrate is cleaned and etched, and then a primer layer, a transition layer and a blackening functional layer are sequentially deposited on the substrate using a magnetron sputtering process or a multi-arc ion plating process; the target material in the deposition process is a Cr target or a Ti target, and the carbon source reaction gas is CH 4 or C 2 H 2 , the working gas is Ar.

[0025] The embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention.

[0026] Example 1 An electronic component includes a substrate and a matte black functional film arranged on the surface of the substrate, wherein the substrate is made of titanium alloy. The matte black functional film includes a base layer, a transition layer and a blackening functional layer deposited in sequence on the substrate, wherein the base layer material is chromium and chromium carbide, the mass percentage ratio of the two is 72%:28%, and the thickness is 0.15 μm; the transition layer material is chromium carbide and a small amount of graphite, the mass percentage ratio of the two is 76%:24%, and the thickness is 0.45 μm; the matte black functional layer material is chromium carbide and a large amount of graphite, the mass percentage ratio of the two is 31%:69%, and the thickness is 2.5 μm.

[0027] When magnetron sputtering technology is used for deposition, the substrate is first cleaned before deposition to remove dirt, oil stains and other residual foreign matter on the surface, and then dried; the Cr target is bombarded with Ar: the working gas Ar is introduced with an Ar flow rate of 500 sccm and a Cr target current of 12 A for 30 min to remove residual foreign matter on the target surface; the dried substrate is placed in a vacuum chamber for preheating and evacuated to a pressure of ≤5.0×10 -3 Pa, preheating temperature is 150℃; Ar bombardment treatment is performed on the preheated substrate: the working gas Ar is introduced, the Ar flow rate is 500 sccm, the bias voltage is 800 V, the bombardment temperature is 150℃, and the time is 30 min to activate the substrate surface and further remove the residual foreign matter on the substrate surface; then chromium and chromium carbide are deposited on the substrate surface to form a base layer: the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2 and working gas Ar, with flow rates of 100 sccm and 400 sccm respectively, bias voltage of 50 V, Cr target current of 10 A, deposition temperature of 150 °C, and deposition time of 10 min; then chromium carbide and a small amount of graphite transition layer are deposited on the surface of the base layer, the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2 and working gas Ar, with flow rates of 100 sccm and 400 sccm respectively, bias voltage of 80 V, Cr target current of 6 A, deposition temperature of 150 °C, and deposition time of 10 min; finally, chromium carbide and a large amount of graphite matte black functional layer are deposited on the surface of the transition layer: the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2 and working gas Ar with flow rates of 400 sccm and 100 sccm respectively, the bias voltage is 50 V, the Cr target current is 4 A, the deposition temperature is 150 °C, and the deposition time is 120 min.

[0028] In Example 1, the matte black functional film deposited on the surface of the electronic component has no obvious scratches on the test surface and the actual damage in the cross-cut area after the adhesive is peeled off does not exceed 5%, and the bonding strength is level 1. In the reflectivity test (GB / T 23981-2009), in the visible light wavelength region, the reflectivity of the matte black functional film is as low as 35%. 1 Comparison of the appearance of electronic components before and after the deposition of the medium matte black functional film is shown in Figure 2 .

[0029] Example 2 A special-shaped electronic component includes a substrate and a matte black functional film arranged on the surface of the substrate, wherein the substrate is made of titanium alloy. The matte black functional film includes a base layer, a transition layer and a blackening functional layer deposited in sequence on the substrate, wherein the base layer material is chromium and chromium carbide, the mass percentage ratio of the two is 78%:22%, and the thickness is 0.2 μm; the transition layer material is chromium carbide and a small amount of graphite, the mass percentage ratio of the two is 71%:29%, and the thickness is 0.5 μm; the matte black functional layer material is chromium carbide and a large amount of graphite, the mass percentage ratio of the two is 33%:67%, and the thickness is 3 μm.

[0030] When magnetron sputtering technology is used for deposition, the substrate is first cleaned before deposition to remove dirt, oil stains and other residual foreign matter on the surface, and then dried; the Cr target is bombarded with Ar: the working gas Ar is introduced with an Ar flow rate of 500 sccm and a Cr target current of 12 A for 30 min to remove residual foreign matter on the target surface; the dried substrate is placed in a vacuum chamber for preheating and evacuated to a pressure of ≤5.0×10 -3 Pa, preheating temperature is 150℃; Ar bombardment treatment is performed on the preheated substrate: the working gas Ar is introduced, the Ar flow rate is 500 sccm, the bias voltage is 800 V, the bombardment temperature is 150℃, and the time is 30 min to activate the substrate surface and further remove the residual foreign matter on the substrate surface; then chromium and chromium carbide are deposited on the substrate surface to form a base layer: the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2 and working gas Ar, with flow rates of 100 sccm and 400 sccm respectively, bias voltage of 50 V, Cr target current of 10 A, deposition temperature of 150 °C, and deposition time of 15 min; then chromium carbide and a small amount of graphite transition layer are deposited on the surface of the base layer, the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2and working gas Ar, with flow rates of 100 sccm and 400 sccm respectively, bias voltage of 80 V, Cr target current of 6 A, deposition temperature of 150 °C, and deposition time of 15 min; finally, chromium carbide and a large amount of graphite matte black functional layer are deposited on the surface of the transition layer: the Cr target is connected to a DC magnetron sputtering power supply, and the carbon source reaction gas C is introduced. 2 H 2 and working gas Ar with flow rates of 400 sccm and 100 sccm respectively, the bias voltage is 50 V, the Cr target current is 4 A, the deposition temperature is 150 °C, and the deposition time is 150 min.

[0031] In the embodiment, the matte black functional film deposited on the surface of the special-shaped electronic component has no obvious scratches on the test surface in the 100-grid test (GB / T9286-1998), and the actual damage in the cross-grid area after the adhesive is peeled off does not exceed 5%, and the bonding strength is level 1. In the reflectivity test (GB / T 23981-2009), in the visible light wavelength region, the reflectivity of the matte black functional film is as low as 38%. The appearance of the special-shaped electronic component after the matte black functional film is deposited is shown in FIG. Figure 3 .

[0032] Comparative Example 1 An electronic component includes a substrate and a matte black film arranged on the surface of the substrate, wherein the substrate is made of titanium alloy, the matte black film is made of chromium carbide, has a thickness of 4 μm, and is prepared by micro-arc oxidation.

[0033] In Comparative Example 1, the appearance of the electronic component is bright gray-black, as shown in Figure 4 In the reflectivity test (GB / T 23981-2009), in the visible light wavelength region, the reflectivity of the matte black film is 72%.

[0034] Comparative Example 2 An electronic component includes a substrate and a matte film arranged on the surface of the substrate, wherein the substrate is made of titanium alloy. The matte film is made of single carbon (DLC), has a thickness of 4 μm, and is prepared by multi-arc ion plating.

[0035] In the reflectivity test (GB / T 23981-2009), the reflectivity of the matte film in Comparative Example 2 in the visible light wavelength region is 25%, but due to the structural characteristics of the DLC coating, the appearance of the electronic components is Figure 5 , showing bright black.

[0036] The above embodiments describe the preferred embodiments of the present invention, but the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the appended claims.

Claims

1. A matte black functional film, characterized in that: It includes a base layer arranged on the surface of the substrate, a transition layer arranged on the base layer, and a blackening functional layer arranged on the transition layer; the base layer is a metal single substance and its carbide, the transition layer is a metal carbide and a small amount of carbon single substance, and the blackening functional layer is a metal carbide and a large amount of carbon single substance.

2. The matte black functional film according to claim 1, characterized in that: The metal in the metal element and the metal carbide is Cr or Ti.

3. The matte black functional film according to claim 1, characterized in that: The mass percentage ratio of the metal element to its carbide in the base layer is 70-80%:20-30%.

4. The matte black functional film according to claim 1, characterized in that: The mass percentage ratio of metal carbide to carbon in the transition layer is 70-80%:20-30%.

5. The matte black functional film according to claim 1, characterized in that: The mass percentage ratio of metal carbide to carbon in the blackening functional layer is 30-40%:60-70%.

6. The matte black functional film according to any one of claims 1 to 5, characterized in that: The total thickness of the matte black functional film is 2.5 μm to 5.5 μm, wherein the thickness of the base layer is 0.1 μm to 0.5 μm, the thickness of the transition layer is 0.4 μm to 1 μm, and the thickness of the blackening functional layer is 2 μm to 4 μm.

7. The method for preparing a matte black functional film according to any one of claims 1 to 5, characterized in that: The substrate is cleaned and etched, and then a base layer, a transition layer and a blackening functional layer are sequentially deposited on the substrate using a magnetron sputtering process or a multi-arc ion plating process; the target material in the deposition process is a Cr target or a Ti target, the carbon source reaction gas is CH4 or C2H2, and the working gas is Ar.

8. The preparation method according to claim 7, characterized in that: When the magnetron sputtering process is used for preparation, the following steps are included: S1, introducing carbon source reaction gas and working gas, the flow rate of carbon source reaction gas is 50 sccm~150 sccm, the flow rate of working gas is 200 sccm~400 sccm, the bias voltage is 50 V~100 V, the target current is 10 A~15 A, the deposition temperature is 120~160°C, and a base layer is deposited on the substrate; S2, introducing carbon source reaction gas and working gas, the flow rate of carbon source reaction gas is 50 sccm~150 sccm, the flow rate of working gas is 200 sccm~600 sccm, the bias voltage is 80 V~120 V, the target current is 6 A~9 A, the deposition temperature is 120~160°C, and a transition layer is deposited on the base layer; S3. Carbon source reaction gas and working gas are introduced, the flow rate of carbon source reaction gas is 50 sccm~150 sccm, the flow rate of working gas is 300 sccm~600 sccm, the bias voltage is 50 V~100 V, the target current is 3 A~5 A, the deposition temperature is 120~160℃, and a blackening functional layer is deposited on the transition layer.

9. The preparation method according to claim 7, characterized in that: When the multi-arc ion plating process is used for deposition, the following steps are specifically included: S1, introducing carbon source reaction gas and working gas, the flow rate of carbon source reaction gas is 200 sccm~300 sccm, the flow rate of working gas is 20 sccm~30 sccm, the bias voltage is 150 V~200 V, the target current is 70 A~90 A, the deposition temperature is 120~160°C, and a base layer is deposited on the substrate; S2, introducing carbon source reaction gas and working gas, the flow rate of carbon source reaction gas is 250 sccm~350 sccm, the flow rate of working gas is 20 sccm~30 sccm, the bias voltage is 100 V~200 V, the target current is 60 A~70 A, the deposition temperature is 120~160°C, and a transition layer is deposited on the base layer; S3. Carbon source reaction gas and working gas are introduced, the flow rate of carbon source reaction gas is 300 sccm~400 sccm, the flow rate of working gas is 20 sccm~30 sccm, the bias voltage is 100 V~150 V, the target current is 50 A~60 A, the deposition temperature is 120~160°C, and a blackening functional layer is deposited on the transition layer.

10. Use of the matte black functional film according to any one of claims 1 to 5 in electronic component coating.

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