Super-hydrophobic matte composite coating and shower head

Abstract

The utility model provides a super-hydrophobic matte composite coating which comprises an ABS (Acrylonitrile Butadiene Styrene) base material, and a bottom layer is electroplated on the surface of the ABS base material; a semi-bright nickel layer, a pearl nickel layer and a trivalent chromium layer are sequentially electroplated on the upper surface of the bottom layer of the ABS base material; under the vacuum condition, ion plating is carried out on the surface of the trivalent chromium layer of the ABS base material to form a silicon dioxide layer with the thickness of 10-20 nm. According to the super-hydrophobic matte composite coating and the shower head, the bottom layer is formed on the ABS base material through electroplating, the semi-bright nickel layer, the pearl nickel layer and the trivalent chromium layer are sequentially electroplated on the upper surface of the bottom layer, the silicon dioxide layer is formed on the surface of the trivalent chromium layer through vacuum ion plating, and the super-hydrophobic matte composite coating which is low in refractive index, high in light transmittance and good in water resistance is formed on the surface of the ABS base material. Meanwhile, a super-hydrophobic micro-nano structure layer in a diffuse scattering matte state is arranged, and a composite coating of the super-hydrophobic micro-nano structure layer has low surface energy and also has super-hydrophobic performance.

Description

Technical Field

[0001] The utility model relates to the technical field of materials, in particular to a composite coating used for material surface treatment and a preparation method thereof. Background Art

[0002] When droplets exist stably on a solid surface, they will present different morphologies, which are represented by the contact angle (CA). The contact angle refers to the tangent of the gas-liquid interface at the intersection of gas, liquid and solid. The angle θ between this tangent on the liquid side and the solid-liquid boundary line has a value range of (0, 180). The critical contact angle value of hydrophobicity is 90°. A value greater than 90° is defined as hydrophobic. The larger the contact angle, the better the hydrophobicity of the surface. The wetting state with a contact angle greater than 150° is defined as superhydrophobic. That is, static droplets tend to maintain a spherical shape on the surface. The study also found that a static contact angle greater than 150° is not enough to characterize hydrophobicity. Therefore, the sliding angle (SA) was introduced to characterize the dynamic wettability. The sliding angle refers to the angle from the inclined surface to the point where the droplet begins to roll. At present, the literature generally defines surfaces with CA>150° and SA<10° as superhydrophobic surfaces.

[0003] Superhydrophobic surfaces with a static contact angle (CA) greater than 150° and a sliding angle (SA) less than 10° play an important role in interface applications due to their excellent waterproofing, self-cleaning, anti-corrosion protection, anti-icing and microfluidic properties.

[0004] Inspired by the super-hydrophobic phenomenon in nature (such as lotus leaves, geckos, rose petals, etc.), many years of research have reached a general consensus that the way to achieve super-hydrophobic properties is to construct a super-hydrophobic surface. According to the classic Wenzel and Cassie model, the two basic factors of appropriate roughness and low surface energy are essential for designing artificial super-hydrophobic surfaces: roughening low-surface-energy materials and reducing the surface energy of rough surfaces. One is to change the roughness through the surface micro-nano composite structure to obtain hydrophobicity; the other is to combine with low-surface-energy materials to reduce the surface energy.

[0005] Kitchen and bathroom products (such as shower heads) are in close contact with tap water, dirt, detergents, etc. during use. Stains are easily left on the surface and are difficult to clean, which affects the appearance and is not conducive to corrosion resistance. There is a real need for super-hydrophobic surfaces. However, the inevitable contact will cause wear of the surface micro-nano structure, and even slight damage to the surface roughness will lead to a significant decrease in hydrophobic performance and failure. At present, the super-hydrophobic surface of kitchen and bathroom products is mainly achieved by powder spraying. The particles used in the spraying technology are mostly colored particles, which is not suitable for metal surfaces and color surfaces with high transparency requirements. A super-hydrophobic micro-nano structure with low refractive index and high light transmittance, diffuse scattering matte state, and low surface energy is obtained for the surface of kitchen and bathroom products, so that the product has super-hydrophobic properties. Utility Model Content

[0006] The utility model aims to provide a super-hydrophobic matte composite coating and a preparation method thereof.

[0007] The technical solution of the utility model is achieved by the following methods:

[0008] The utility model discloses a super-hydrophobic matte composite coating, comprising an ABS substrate, a bottom layer electroplated on the surface of the ABS substrate; a semi-bright nickel layer, a pearl nickel layer and a trivalent chromium layer are electroplated on the upper surface of the bottom layer of the ABS substrate in sequence; under vacuum conditions, a silicon dioxide layer with a thickness of 10-20nm is formed by ion plating on the surface of the trivalent chromium layer of the ABS substrate.

[0009] As a further limitation of the present invention, the bottom layer is a bright copper layer, which is used for electroplating on the upper surface of the ABS substrate.

[0010] As a further limitation of the present invention, the raw material components of the semi-bright nickel layer include the following components: nickel sulfate NiSO 4 -6H 2 O concentration is 260-340g / L, nickel chloride NiCl-5H 2 O concentration is 35-55g / L and boric acid H 3 BO 3 The concentration is 30-65g / L.

[0011] As a further limitation of the present invention, the pearl nickel layer is electroplated using an electroplating solution having the following components: nickel sulfate NiSO 4 -6H 2 O concentration is 450-530g / L, nickel chloride NiCl-5H 2 O concentration is 25-55g / L, boric acid H 3 BO 3 Concentration is 30-50g / L, saccharin sodium C 7 H 4 NNaO 3The S concentration is 90-110 g / L and the octylphenol polyvinyl ether concentration is 15-40 g / L.

[0012] As a further limitation of the present invention, the raw material components of the trivalent chromium layer include the following components: butynediol BOZ concentration of 0.1-0.2 g / L, boric acid H 3 BO 3 The concentration is 43-83g / L and the concentration is 11-31g / L of trivalent chromium ions.

[0013] As a further limitation of the present invention, the silicon dioxide layer is coated on a silicon target with a purity of 99.99% by medium-frequency magnetron sputtering, a medium-frequency power supply with a frequency of 40KHZ, Ar as the sputtering gas, and O2 as the reaction gas.

[0014] The utility model also discloses a method for preparing a super-hydrophobic matte composite coating, which is applied to the above-mentioned super-hydrophobic matte composite coating, and the preparation steps include:

[0015] S1. Electroplating a semi-bright nickel layer, electroplating a semi-bright nickel layer on a clean ABS substrate;

[0016] S2. electroplating a pearl nickel layer, electroplating a pearl nickel layer on the obtained semi-nickel light layer;

[0017] S3. electroplating a trivalent chromium layer, and performing a trivalent chromium layer electroplating treatment on the obtained pearl nickel layer;

[0018] S4. vacuum coating, magnetron sputtering silicon dioxide layer on the trivalent chromium layer of the cleaned and dried ABS substrate.

[0019] As a further limitation of the present invention, the electroplating solution for the trivalent chromium layer comprises: 0.1-0.2 g / L butynediol BOZ, 43-83 g / L boric acid H 3 BO 3 and 11-31g / L metal chromium anode electrochemical dissolution, the process conditions are: pH value 2.4-3, temperature 30-40℃, current density 2.5-4.5A / dm 2 , time is 950-1150s.

[0020] As a further limitation of the present invention, the electroplating solution components of the semi-nickel light layer include: nickel sulfate NiSO 4 -6H 2 O concentration 260-340g / L, nickel chloride NiCl-5H 2 O concentration 35-55g / L and boric acid H 3 BO 3The concentration is 30-65g / L; the process conditions are: working time is 1100-1250s, pH range is 3.7-4.3, current is 1100A, current density is 2.5-4.5A / dm 2 .

[0021] As a further limitation of the present invention, the electroplating solution components of the pearl nickel layer include: nickel sulfate NiSO 4 -6H 2 O concentration 450-530g / L, nickel chloride NiCl-5H 2 O concentration 2555g / L, boric acid H 3 BO 3 Concentration 30-50g / L, saccharin sodium C 7 H 4 NNaO 3 The S concentration is 90-110g / L, the octylphenol polyvinyl ether concentration is 15-40g / L, and the process conditions are: electroplating time is 400-480s, pH value is 3.8-4.4, temperature is 50℃-60℃, current is 1600A, current density is 2.5-4.5A / dm 2 .

[0022] As a further limitation of the present invention, the ABS substrate treated by electroplating in S4 is cleaned and dried and placed in a vacuum chamber. When the vacuum is 1*10 -3 Pa, argon gas was introduced and the pressure of the vacuum chamber was adjusted to 2*10 -3 Pa, pulse bias is 120V, duty cycle is 20%, vacuum is evacuated to 1.0*10Pa, sputtering pressure is 1.2Pa, argon is used to pre-sputter the target surface for more than 10min to remove surface oxides and other impurities, oxygen is introduced, sputtering power is 0.8-2KW, oxygen flow rate is 20-50sccm, argon flow rate is 150-200sccm, sputtering pressure is 0.6Pa, sputtering deposition time is 30-60mim, and it is taken out after cooling.

[0023] A shower head comprises a shower head body, the surface of which is plated with the above-mentioned super-hydrophobic matte composite coating.

[0024] Beneficial effects of the super-hydrophobic matte composite coating and the preparation method thereof:

[0025] The composite coating surface of the ABS substrate has numerous lotus leaf-like micro-nano circular pits with compact overlapping structures. The surface roughening has a diffuse reflection effect on light refraction, high astigmatism, structural contact angle CA>153°, and rolling angle SA<10°. The sputtered silicon dioxide layer is a polyhedral network structure ion crystal coating with a dielectric constant>3.9, low surface energy characteristics, and super hydrophobicity. The surface morphology of the silicon dioxide layer is smooth and dense, abrasion-resistant, and has high light transmittance, and can present a matte super hydrophobic composite coating with pearl satin color. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0027] Figure 1 This is a schematic diagram of the structure of a super-hydrophobic matte composite coating of a shower head of the utility model;

[0028] Figure 2 The utility model is a flow chart of a method for preparing a super-hydrophobic matte composite coating.

[0029] Figure 3a-3d This is the microscopic morphology of the super-hydrophobic matte composite coating of Example 1 of the utility model under a JSM-6700F cold field emission scanning electron microscope.

[0030] Figure 4a It is a schematic diagram of the contact angle CA and the rolling angle SA of the super-hydrophobic matte composite coating of Example 1 of the present invention.

[0031] Figure 4b The contact angle CA and the rolling angle SA of the super-hydrophobic matte composite coating of Example 1 of the utility model are tested by a JC2000C1 contact angle measuring instrument, and a micro-injector is used to drop deionized water liquid. The volume of each drop of liquid is about 8 μL. The angle measurement method is used for testing, wherein the contact angle CA in the left figure is greater than 150°, and the rolling angle SA in the right figure is less than 10°.

[0032] Figure 5This is a characteristic diagram of the durability of the surface superhydrophobic performance of the superhydrophobic matte composite coating after the tangential wear test of Example 1 of the utility model, wherein the prepared superhydrophobic sample is placed face down on 1.7μm (1500 mesh) sandpaper, and a weight of 10g is applied to the sample, and then the sample is moved at a speed of 5mm / s. The contact angle of the sample is measured every 5s. After 60s, the sample still has a contact angle of more than 150°, indicating that the measured sample has good durability.

[0033] Figure 6 This is a characteristic diagram of the durability of the surface super-hydrophobic performance of the super-hydrophobic matte composite coating of Example 1 of the utility model after the impact test, wherein, by using sand particles with a diameter of 120 to 260 μm as impact objects, an impact test is performed on the sample surface tilted at 45° to test the mechanical durability of the super-hydrophobic composite coating prepared by the utility model. This impact can significantly change the microscopic morphology of the surface, thereby completely destroying the super-hydrophobic performance of the surface. The sand particle impact experiment shows that after the sand layer is impacted from a height of 2 m for 15 minutes, the static contact angle of water does not change, and the sliding angle increases to 30°. The test shows that its surface still maintains super-hydrophobic properties.

[0034] Figure 7 The super-hydrophobic matte composite coating of Example 1 of the present invention is subjected to an extinction rate test (silicon dioxide layer transparency test) by an infrared spectrometer, and the refraction characteristic diagrams under different sputtering power conditions are compared.

[0035] Reference numerals: ABS substrate 10; bright copper layer 101; semi-bright nickel layer 20; pearl nickel layer 30; trivalent chromium layer 40; silicon dioxide layer 60 DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] Example 1

[0038] like Figure 1 and Figure 2As shown, the utility model provides a shower head, comprising a shower head body, the shower head body is an ABS substrate 10, and a super-hydrophobic matte composite coating is formed on the surface of the shower head body. First, on the basis of pre-treating the surface of the shower head body to form an electroplated bottom layer, a semi-bright nickel layer 20, a pearl nickel layer 30 and a trivalent chromium layer 40 are electroplated in sequence on the upper surface of the bottom layer of the ABS substrate 10 to form a hydrophobic structure layer; and under vacuum conditions, ion plating is performed on the surface of the hydrophobic structure layer of the ABS substrate 10 to form a 10-20nm thick silicon dioxide layer 60 to form a super-hydrophobic matte composite coating, which has low surface energy characteristics and super-hydrophobicity, and also has the characteristics of being smooth and dense, abrasion-resistant, high light transmittance, and high light dispersion, and can present a matte effect of pearl satin color.

[0039] The ABS substrate 10 is pretreated to form a bright copper layer 101 on the surface of the ABS substrate 10. Specifically, the electroplating-grade ABS substrate 10 is pretreated by roughening, reduction, pre-impregnation, palladium activation, debonding, pre-nickel plating, and bright copper. The specific steps include:

[0040] (1) Roughening: the roughening electroplating solution is 300-400g / L chromic anhydride and 350-400g / L sulfuric acid. The process conditions are: working temperature is 35-55°C, and the roughening time is 450-900s. The roughened surface is washed with water for 10-20s.

[0041] (2) Reduction: The roughened ABS substrate 10 is placed in 30-40 ml / L stannous chloride SnCl2 for reduction for 60-100 seconds; after reduction, it is washed with water for 10-15 seconds;

[0042] (3) pre-dipping, pre-dipping the reduced ABS substrate 10 in hydrochloric acid with a concentration of 180-250 mL / L for 120-130 seconds;

[0043] (4) Palladium activation: soak the pre-impregnated ABS substrate 10 in a composite activation solution of 200-300 ml / L hydrochloric acid, 25 g / L stannous chloride and 30-50 ppm palladium chloride PdCl2 for 180-200 seconds at room temperature, and wash with water after soaking;

[0044] (5) Degumming: immersing the palladium-activated ABS substrate 10 in a 50 g / L sodium hydroxide solution for 60-120 seconds. The ABS substrate 10 does not deform. After degumming, the substrate is washed with water.

[0045] (6) Pre-nickel plating: the debonded ABS substrate 10 is pre-plated with nickel, and the electroplating solution composition is: nickel sulfate NiSO 4 -7H 2 O concentration 220-300g / L, nickel chloride NiCl-5H 2 O concentration 40-60g / L, boric acid H3 BO 3 Concentration 30-50g / L; pH value 3.7-4.3, temperature 50-60℃, time 420-440s, current 1100A, current density 1.5-3.0A / dm 2 ; and wash with water;

[0046] (7) Bright copper: The ABS substrate 10 pre-nickel-plated is electroplated with copper to form a bright copper layer. The electroplating solution composition is: copper sulfate CuSO 4 Concentration 160-240g / L, sodium chloride NaCI concentration 8-10g / L, time 220-300s, temperature 22-30℃, current 1200A, current density 2.5-4.5A / dm 2 .

[0047] Before electroplating the semi-bright nickel layer 20, the pre-treated ABS substrate 10 is acid activated, that is, in a sulfuric acid H2O with a concentration of 20-30 ml / L. 2 SO 4 Soak in room temperature for 60 seconds, take out and wash with water. 2 O concentration 3555g / L and boric acid H 3 BO 3 Concentration 30-65g / L electroplating; process conditions: time 1100-1250s, pH value 3.7-4.3, current 1100A, current density 2.5-4.5A / dm 2 , and wash with water.

[0048] The pearl nickel layer 30 is electroplated on the surface of the semi-bright nickel layer 20, and the electroplating solution composition is: nickel sulfate NiSO 4 -6H 2 O concentration is 450-530g / L, nickel chloride NiCl-5H 2 O concentration is 25-55g / L, boric acid H 3 BO 3 Concentration 30-50g / L, saccharin sodium C 7 H 4 NNaO 3 The S concentration is 90-110g / L, the octylphenol polyvinyl ether (OP-10) concentration is 15-40g / L, and the process conditions are: electroplating time 400-480s, pH value 3.8-4.4, temperature 50℃-60℃, current 1600A, current density 2.5-4.5A / dm 2 , and wash with water.

[0049] Trivalent chromium layer 40, electroplate trivalent chromium on the surface of the pearl nickel layer 30, and the components of the electroplating solution are: 0.1 - 0.2 g / L butynediol BOZ, 43 - 83 g / L boric acid H 3 BO 3 and 11 - 31 g / L of electrochemically dissolved metal chromium anode, pH value is 2.4 - 3, temperature is 30 - 40 °C, current density is 2.5 - 4.5 A / dm 2 , and the time is 950 - 1150 s; after electroplating, carry out hot water washing and drying under the conditions of temperature 40 °C - 60 °C and time 140 - 160 s; the drying temperature is 40 °C - 55 °C, and the drying time is 1600 - 1800 s.

[0050] Silicon dioxide layer 60, subject the ABS substrate 10 to pretreatment, electroplate a semi-bright nickel layer 20, a pearl nickel layer 30 and a trivalent chromium layer 40 to form a hydrophobic structure layer, wash it and place it in a vacuum chamber, evacuate with a mechanical pump and a molecular pump. When the vacuum reaches 1×10 -3 Pa, close the high valve and introduce argon gas, adjust the air pressure in the vacuum chamber to 20 Pa by adjusting the argon gas flow rate, turn on the pulsed bias voltage, the power supply voltage is 120 V, and the duty cycle is 20%. Evacuate to 1.0×10 Pa, the sputtering air pressure is 1.2 Pa, pre-sputter the surface of the target with argon gas for more than 10 minutes to remove oxides and other impurities on the surface of the target, introduce oxygen gas into the vacuum chamber, open the baffle after the glow is stable, keep the sputtering power at 0.8 KW, the oxygen gas flow rate is 20 sccm, the argon gas flow rate is 150 sccm, the sputtering air pressure is 0.6 Pa, and the sputtering deposition time is 30 minutes to complete vacuum ion plating. Continue to operate the cooling system for 1 hour, open the vacuum chamber and take out. The thickness of the silicon dioxide layer 60 is 10 nm.

[0051] It should be noted that after pretreatment of the ABS substrate 10, a semi-bright nickel layer, a pearl nickel layer and a trivalent chromium layer are electroplated on the surface in sequence, and a silicon dioxide layer is formed by ion plating under vacuum conditions. Therefore, a super-hydrophobic matte composite coating is formed on the surface of the ABS substrate. The composite coating surface has countless micro-nano circular concave cavities similar to lotus leaves in a tightly overlapping structure. The surface roughening of the composite coating results in a diffuse reflection state for the light refraction effect. The contact angle CA of the structure is >153°, and the rolling angle SA < 10°. The sputtered silicon dioxide layer is a polyhedral network structure ionic crystal coating, with a dielectric constant > 3.9, having low surface energy characteristics and super-hydrophobicity. It can be seen from the measurement and analysis of the surface topography obtained by atomic force microscopy AFM that the surface topography of the silicon dioxide thin film is smooth and dense, (density > 2.2 g / cm - 3), wear-resistant. The silicon dioxide coating particles have a high light transmittance (refractive index 1.1 - 1.46) and a high light scattering rate (glossiness 20 < GU), presenting a matte super-hydrophobic composite coating of ABS products with a pearl satin surface color.

[0052] Example 2

[0053] The preparation method is basically the same as that of Example 1, except that, for the vacuum coating of the silicon dioxide layer 60, the vacuum chamber is maintained to maintain the sputtering power in the range of 1.5KW, the oxygen flow rate is 35sccm, the argon flow rate is 180sccm, the sputtering pressure is 0.6Pa, the sputtering deposition time is 45min, the vacuum ion plating is completed, the cooling system is continued to operate for 1 hour, the vacuum chamber is opened and taken out, and the thickness of the silicon dioxide layer 60 is 14nm.

[0054] Example 3

[0055] The preparation method is basically the same as that of Example 1, except that, for the vacuum coating of the silicon dioxide layer 60, the vacuum chamber maintains the sputtering power in the range of 2 kW, the oxygen flow rate is 50 sccm, the argon flow rate is 200 sccm, the sputtering pressure is 0.6 Pa, the sputtering deposition time is 60 min, the vacuum ion plating is completed, the cooling system is continued to operate for 1 hour, the vacuum chamber is opened and taken out, and the thickness of the silicon dioxide layer 60 is 20 nm.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A super-hydrophobic matte composite coating, characterized in that: include: ABS substrate, the surface of ABS substrate is electroplated with a bottom layer; The upper surface of the bottom layer of the ABS substrate is electroplated with a semi-bright nickel layer, a pearl nickel layer and a trivalent chromium layer in sequence; Under vacuum conditions, a silicon dioxide layer with a thickness of 10-20 nm is formed by ion plating on the surface of the trivalent chromium layer of the ABS substrate.

2. The super-hydrophobic matte composite coating according to claim 1, characterized in that: The bottom layer is a bright copper layer, which is used for electroplating on the upper surface of the ABS substrate.

3. The super-hydrophobic matte composite coating according to claim 2, characterized in that: The silicon dioxide layer is coated with a silicon target having a purity of 99.99% by medium frequency magnetron sputtering, a medium frequency power supply having a frequency of 40 kHz, Ar as a sputtering gas, and O2 as a reaction gas.

4. A shower head, comprising a shower head body, characterized in that: The surface of the shower body is coated with the super-hydrophobic matte composite coating as claimed in any one of claims 1 to 3.

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