Method for coloring h65 copper to resemble h85 copper

Abstract

The application provides a method for coloring H65 copper into H85 copper, which comprises the following steps: sequentially removing oil, washing once, activating, washing twice, coloring, washing thrice, passivating, washing four times, drying and painting on the H65 copper blank. The application fundamentally changes the copper-zinc ratio on the surface of the H65 copper, increases the copper content and reduces the zinc content. By controlling the effective concentration of the coloring solution, the temperature and the coloring time, the appearance color of H85 copper can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of copper, and in particular relates to a method for imitating the color of H85 copper with H65 copper. Background Art

[0002] Currently, brass zippers are primarily made of H85 copper, while domestically produced brass zippers are primarily made of H65 copper. The difference in tooth color is significant. Both H85 and H65 copper have a brass-colored appearance, but H85 copper is slightly redder than H65, closer to true gold. H65 copper, on the other hand, has a heavier bluish sheen, making it appear lower-end and priced lower. If H65 copper could achieve the appearance and color of H85 copper, its economic value would be greater. Currently, brass zippers are expensive, cheap, and weak. Summary of the Invention

[0003] In view of this, the purpose of the embodiment of the present invention is to provide a method for imitating the color of H85 copper with H65 copper. The present invention uses lower-cost H65 copper to replace the higher-cost H85 copper material to produce brass zippers, thereby achieving the purpose of reducing costs, improving quality and increasing efficiency.

[0004] The present invention provides a method for imitating the color of H85 copper with H65 copper, comprising:

[0005] The H65 copper billet is sequentially degreased, washed once, activated, washed twice, colored, washed three times, passivated, washed four times, dried and painted.

[0006] Preferably, the oil removal is alkaline oil removal, and the oil removal reagent includes:

[0007] Sodium carbonate, sodium phosphate, sodium silicate, emulsifier and water.

[0008] Preferably, the content of sodium carbonate in the oil removal reagent is 5 to 10 g / L;

[0009] The content of the sodium phosphate in the oil removal reagent is 25-50 g / L;

[0010] The content of sodium silicate in the oil removal reagent is 5 to 10 g / L;

[0011] The content of the emulsifier in the oil removal reagent is 5-10 ml / L.

[0012] Preferably, the degreasing temperature is 40 to 60° C., and the degreasing time is 30 to 60 seconds.

[0013] Preferably, the activation is performed using a sulfuric acid solution, and the volume concentration of the sulfuric acid solution is 1 to 3%.

[0014] Preferably, the coloring liquid used for coloring includes:

[0015] Ammonium chloride, copper sulfate, sodium chloride, and water.

[0016] Preferably, the content of ammonium chloride in the coloring liquid is 50 to 200 g / L;

[0017] The content of copper sulfate in the coloring liquid is 0.01-0.2 g / L;

[0018] The content of sodium chloride in the coloring liquid is 1-10 g / L.

[0019] Preferably, the coloring temperature is 75 to 85° C., and the coloring time is 30 to 120 seconds.

[0020] Preferably, the passivation solution used for the passivation is a chromium-free passivation solution for brass.

[0021] Preferably, the passivation temperature is room temperature, and the passivation time is 30 to 120 seconds.

[0022] The Cu element in H65 copper accounts for about 65%, the Zn element accounts for about 35%, and the rest are several trace elements; the NH4Cl in the coloring formula will produce NH3 and HCl when heated, which are ammonia water and hydrochloric acid in aqueous solution. The system pH is about 5.5 and is acidic. Hydrochloric acid reacts with the Zn element in H65 copper to produce Zn 2+ Ions enter the solution and react with NH3 to form the more stable Zn(NH3)4 2+ Complex ions, the equilibrium shifts to the right, the oxidation of elemental Zn continues, the copper-zinc ratio on the surface of H65 copper changes, the copper content increases, and the zinc content decreases. CuO exists on the surface of H65 copper and reacts with HCl to form Cu 2+ The ions enter the solution and undergo a replacement reaction with elemental Zn at the solid-liquid interface between H65 copper and the aqueous phase to generate elemental Cu deposited on the surface of H65 copper. Due to the presence of dissolved oxygen in the solution, the Cu element on the surface of H65 copper reacts with HCl to generate Cu 2+ The ions enter the solution and undergo a replacement reaction with elemental Zn at the solid-liquid interface between the H65 copper and the aqueous phase, forming elemental Cu that is deposited on the H65 copper surface. Simultaneously, the inherent CuSO₄ in the formula also undergoes a replacement reaction with the Zn on the H65 copper surface, forming elemental Cu that is also deposited on the H65 copper surface. Overall, the original copper-zinc ratio on the H65 copper surface undergoes a fundamental change, with the copper content increasing and the zinc content decreasing. By controlling the effective concentration, temperature, and coloring time of the coloring solution, the appearance of H85 copper can be achieved. DETAILED DESCRIPTION

[0023] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0024] The present invention provides a method for imitating the color of H85 copper with H65 copper, comprising:

[0025] The H65 copper billet is sequentially degreased, washed once, activated, washed twice, colored, washed three times, passivated, washed four times, dried and painted.

[0026] In the embodiment of the present invention, the H65 copper blank may be a common brass zipper in the industry well known in the art.

[0027] In the present invention, the degreasing is preferably alkaline degreasing, and the degreasing agent preferably includes:

[0028] Sodium carbonate, sodium phosphate, sodium silicate and emulsifiers.

[0029] In an embodiment of the present invention, the oil removal agent does not contain water.

[0030] In the present invention, the content of sodium carbonate in the oil removal reagent is preferably 5-10 g / L, more preferably 6-9 g / L, and most preferably 7-8 g / L; the content of sodium phosphate in the oil removal reagent is preferably 25-50 g / L, more preferably 30-45 g / L, and most preferably 35-40 g / L; the mass content of sodium silicate in the oil removal reagent is preferably 5-10 g / L, more preferably 6-9 g / L, and most preferably 7-8 g / L; the emulsifier is preferably emulsifier MOA-9; the content of the emulsifier in the oil removal reagent is preferably 5-10 ml / L, more preferably 6-9 ml / L, and most preferably 7-8 ml / L.

[0031] In the present invention, the degreasing temperature using the degreasing agent is preferably 40-50°C, more preferably 42-48°C, and most preferably 44-46°C; the degreasing time is preferably 30-60 seconds, more preferably 40-50 seconds, and most preferably 45 seconds.

[0032] In the present invention, the alkaline degreasing can also be performed using commercially available copper alkaline degreasing powder, such as the HP-201 product provided by Guangdong Huapu Company; during use, the copper alkaline degreasing powder is preferably prepared into a solution with a mass concentration of 1 to 3%, more preferably a 2% solution; the temperature for degreasing using the copper alkaline degreasing powder is preferably 40 to 60°C, more preferably 45 to 55°C, and most preferably 50°C; the time is preferably 30 to 60 seconds, more preferably 40 to 50 seconds, and most preferably 45 seconds.

[0033] In the present invention, the one-time water washing is preferably thorough water washing.

[0034] In the present invention, the activation is preferably performed using a sulfuric acid solution, and the volume concentration of the sulfuric acid solution is preferably 1 to 3%, more preferably 1.5 to 2.5%, and most preferably 2%.

[0035] In an embodiment of the present invention, the activation temperature during the activation process can be selected from 10 to 30° C., such as 15° C., 20° C., and 25° C.; the activation time can be selected from 5 to 30 seconds, such as 10 seconds, 15 seconds, 20 seconds, and 25 seconds.

[0036] In the present invention, the degreasing and activation process is very important. Oil stains and copper oxide film will make the colored film layer uneven or even not colored.

[0037] In the present invention, the secondary water washing is preferably thorough water washing.

[0038] In the present invention, the coloring is to use a coloring liquid with the color of H65 copper imitating H85 copper; the coloring liquid preferably includes:

[0039] Ammonium chloride, copper sulfate, sodium chloride, and water.

[0040] In the present invention, the content of ammonium chloride in the coloring liquid is preferably 50-200 g / L, more preferably 100-150 g / L, and most preferably 120-130 g / L; the content of copper sulfate in the coloring liquid is preferably 0.01-0.2 g / L, more preferably 0.05-0.15 g / L, more preferably 0.08-0.12 g / L, and most preferably 0.1 g / L; the mass content of sodium chloride in the coloring liquid is preferably 1-10 g / L, more preferably 2-8 g / L, more preferably 3-6 g / L, and most preferably 4-5 g / L.

[0041] In the present invention, the preparation method of the coloring liquid preferably includes:

[0042] Dissolve ammonium chloride, copper sulfate and sodium chloride in a small amount of water respectively, then add them together to dilute to the required concentration.

[0043] In the present invention, the coloring temperature is preferably 75-85°C, more preferably 78-82°C, and most preferably 80°C; the coloring time is preferably 30-120 seconds, more preferably 50-100 seconds, and most preferably 60-80 seconds.

[0044] In an embodiment of the present invention, the reaction formula occurring during the coloring process may include:

[0045] NH4Cl (heating) → NH3 + HCl

[0046] Zn+2HCl→ZnCl2+H2↑

[0047] ZnCl2+4NH3→Zn(NH3)4Cl2

[0048] CuO + 2HCl → CuCl2 + H2O

[0049] 2Cu+4HCl+O2→2CuCl2+2H2O

[0050] CuCl2+Zn→Cu↓+ZnCl2

[0051] CuSO4+Zn→Cu↓+ZnSO4.

[0052] In the present invention, the three water washings are preferably thorough water washings.

[0053] In the present invention, the passivation solution used for the passivation is preferably a commercially available chromium-free brass passivation solution, such as the CT-806 copper protectant provided by Shenzhen Yuetian New Materials Technology Co., Ltd.; the passivation solution is preferably resistant to 5% salt spray for 24 hours and high temperature and high humidity for 3 days. In the present invention, the passivation solution is preferably diluted with water to obtain a passivation solution with a mass concentration of 3-7%, more preferably 4-6%, and most preferably 5%. In the present invention, the passivation temperature is preferably room temperature; the passivation time is preferably 30-120 seconds, more preferably 50-100 seconds, and most preferably 60-80 seconds.

[0054] In the present invention, the four water washings are preferably thorough water washings.

[0055] In an embodiment of the present invention, the painting reagents in the dry painting process may include:

[0056] Paint, hardener and thinner.

[0057] In the embodiments of the present invention, there is no special limitation on the paint, curing agent and diluent. Those skilled in the art can select suitable paint and matching curing agent according to the reagent requirements so as to achieve painting. The mass ratio of paint, curing agent and diluent can be selected from 1: (0.5-1): (0.1-0.5), such as 1: (0.6-0.9): (0.2-0.4), 1: (0.7-0.8): 0.3.

[0058] In an embodiment of the present invention, the temperature for drying the paint can be selected from 125 to 140°C, such as 130°C, 135°C; the time for drying the paint on one side can be selected from 5 to 10 minutes, such as 6 minutes, 7 minutes, 8 minutes, and 9 minutes.

[0059] The Cu element in H65 copper accounts for about 65%, the Zn element accounts for about 35%, and the rest are several trace elements; the NH4Cl in the coloring formula will produce NH3 and HCl when heated, which are ammonia water and hydrochloric acid in aqueous solution. The system pH is about 5.5 and is acidic. Hydrochloric acid reacts with the Zn element in H65 copper to produce Zn 2+ Ions enter the solution and react with NH3 to form the more stable Zn(NH3)4 2+ Complex ions, the equilibrium shifts to the right, the oxidation of elemental Zn continues, the copper-zinc ratio on the surface of H65 copper changes, the copper content increases, and the zinc content decreases. CuO exists on the surface of H65 copper and reacts with HCl to form Cu 2+ The ions enter the solution and undergo a replacement reaction with elemental Zn at the solid-liquid interface between H65 copper and the aqueous phase to generate elemental Cu deposited on the surface of H65 copper. Due to the presence of dissolved oxygen in the solution, the Cu element on the surface of H65 copper reacts with HCl to generate Cu 2+ The ions enter the solution and undergo a replacement reaction with elemental Zn at the solid-liquid interface between the H65 copper and the aqueous phase, forming elemental Cu that is deposited on the H65 copper surface. Simultaneously, the inherent CuSO₄ in the formula also undergoes a replacement reaction with the Zn on the H65 copper surface, forming elemental Cu that is also deposited on the H65 copper surface. Overall, the original copper-zinc ratio on the H65 copper surface undergoes a fundamental change, with the copper content increasing and the zinc content decreasing. By controlling the effective concentration, temperature, and coloring time of the coloring solution, the appearance of H85 copper can be achieved.

[0060] The H65 copper used in the following embodiments of the present invention is a common brass zipper in the industry.

[0061] Example 1

[0062] The H65 copper billet is sequentially subjected to alkaline degreasing, thorough water washing, 2% sulfuric acid activation, thorough water washing, H65 copper imitation H85 copper coloring, thorough water washing, passivation treatment, thorough water washing, drying and transparent coating to obtain an imitation H85 copper product;

[0063] The degreasing agent in the alkaline degreasing process is HP-201 solution with a mass concentration of 2%, a degreasing temperature of 50°C, and a degreasing time of 45 seconds;

[0064] During the sulfuric acid activation process, the volume concentration of the sulfuric acid solution is 2%, the activation temperature is 25° C., and the activation time is 20 seconds;

[0065] The coloring liquid comprises: ammonium chloride, copper sulfate, sodium chloride and water, wherein the concentration of ammonium chloride in the coloring liquid is 50 g / L, the concentration of copper sulfate in the coloring liquid is 0.2 g / L, and the concentration of sodium chloride in the coloring liquid is 10 g / L; the coloring temperature is 85° C., and the coloring time is 120 s;

[0066] During the passivation treatment, the mass ratio of the passivation solution (CT-806 copper protective agent provided by Shenzhen Yuetian New Material Technology Co., Ltd.) to water was 1:10; the passivation temperature was 25° C., and the passivation time was 60 s;

[0067] In the drying transparent painting process, suitable paint and matching curing agent and thinner can be selected according to reagent requirements. The mass ratio of paint, curing agent and thinner is 1:1:0.5; the drying temperature is 130°C; and the single-side drying time is 6 minutes.

[0068] Example 2

[0069] An imitation H85 copper product was prepared according to the method of Example 1. The difference from Example 1 is that the coloring liquid includes: ammonium chloride, copper sulfate, sodium chloride and water, the concentration of ammonium chloride in the coloring liquid is 100 g / L, the concentration of copper sulfate in the coloring liquid is 0.1 g / L, and the concentration of sodium chloride in the coloring liquid is 5 g / L; the coloring temperature is 80°C, the coloring time is 60 seconds, the passivation time is 90 seconds, and the mass ratio of paint, curing agent and diluent during the painting process is 1:1:0.3.

[0070] Example 3

[0071] An imitation H85 copper product was prepared according to the method of Example 1. The difference from Example 1 was that the mass concentration of the degreaser was 3%; the sulfuric acid activation time was 15 seconds; the coloring liquid included: ammonium chloride, copper sulfate, sodium chloride and water, the concentration of ammonium chloride in the coloring liquid was 150 g / L, the concentration of copper sulfate in the coloring liquid was 0.1 g / L, and the concentration of sodium chloride in the coloring liquid was 2 g / L; the coloring temperature was 75° C., the coloring time was 50 seconds, and the passivation time was 90 seconds. During the painting process, the mass ratio of paint, curing agent and diluent was 1:1:0.3.

[0072] Performance testing

[0073] The imitation H85 copper product prepared in the embodiment of the present invention was made into a zipper according to the general zipper processing technology. The prepared zipper was systematically tested according to the SAB zipper company's testing standards. The test results are as follows:

[0074]

[0075] Judging from the above results, Case 3 has the best effect. The present invention uses low-cost and high-strength H65 copper substrate to replace the high-cost H85 copper substrate to produce copper products with H85 copper appearance and color, achieving the purpose of reducing costs and improving quality.

[0076] Although the present invention has been described and illustrated with reference to specific embodiments of the present invention, these descriptions and illustrations do not limit the present invention. It will be clearly understood by those skilled in the art that, without departing from the true spirit and scope of the present invention as defined by the appended claims, various changes may be made to make specific circumstances, materials, compositions of matter, substances, methods or processes suitable for the object, spirit and scope of the present application. All such modifications are intended to be within the scope of the appended claims. Although the methods disclosed herein have been described with reference to specific operations performed in a specific order, it will be understood that these operations may be combined, subdivided or reordered to form equivalent methods without departing from the teachings of the present invention. Therefore, unless otherwise indicated herein, the order and grouping of operations are not limitations of the present application.

Claims

1. A method for imitating the color of H65 copper with H85 copper, comprising: The H65 copper billet is sequentially subjected to degreasing, primary water washing, activation, secondary water washing, coloring, tertiary water washing, passivation, quaternary water washing, drying and painting; The coloring liquid used in the coloring is composed of ammonium chloride, copper sulfate, sodium chloride and water; The content of ammonium chloride in the coloring liquid is 50-150 g / L; The content of copper sulfate in the coloring liquid is 0.01-0.2 g / L; The content of sodium chloride in the coloring liquid is 1-10 g / L; The passivation solution used in the passivation is a chromium-free passivation solution for brass; the mass concentration of the passivation solution is 3-7%; The passivation temperature is room temperature, and the passivation time is 30 to 120 seconds; The H65 copper is composed of Cu, Zn and other trace elements; through the coloring and passivation process, the copper-zinc ratio on the surface of the H65 copper is changed, the copper content is increased and the zinc content is reduced; The coloring temperature is 75-85°C.

2. The method according to claim 1, characterized in that The oil removal is alkaline oil removal, and the oil removal reagent includes: Sodium carbonate, sodium phosphate, sodium silicate, emulsifier and water.

3. The method according to claim 2, characterized in that The content of sodium carbonate in the oil removal reagent is 5-10 g / L; The content of the sodium phosphate in the oil removal reagent is 25-50 g / L; The content of sodium silicate in the degreasing agent is 5-10 g / L; The content of the emulsifier in the oil removal reagent is 5-10 ml / L.

4. The method according to claim 1, wherein The degreasing temperature is 40-60° C., and the degreasing time is 30-60 seconds.

5. The method according to claim 1, wherein The activation is performed using a sulfuric acid solution, wherein the volume concentration of the sulfuric acid solution is 1-3%.

6. The method according to claim 1, characterized in that The coloring time is 30 to 120 seconds.

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