JPS5928633B2 - How to bronze copper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copper bronze coloring method in which a material such as iron is plated with copper and is immersed in a bronze solution containing potassium sulfide as a main component to create a black color. It is.

The conventional copper bronze coloring method involves performing copper strike or nickel strike to improve adhesion after electrolytic degreasing and water washing, and then automatically copper plating with copper sulfate, copper bronze, or copper pyrophosphate.

Next, it is either dried manually or immersed in a neutralizing solution and then immersed in a bronze solution based on conventional experience to give it a bronze color. Based on this experience, it has been pointed out that in the bronze coloring method, consistent automation from the copper plating process to the bronze coloring process is impossible, and there are problems in that uneven coloring and products with poor adhesion occur one after another. The present invention
This problem is solved by a bronze coloring method in which copper plating is washed with water and then immersed in a bronze solution containing potassium sulfide as a main component to be colored black. Potassium sulfide concentration 3g/j! ,
Less than 3 g per liter is added to the bronze solution, preferably less than 2 g/g.
After immersing for less than 0 seconds, the process of leaving the material in the air for the same amount of time is repeated once or twice to form a uniform colored adhesion, and then immersing again for an appropriate time to obtain the desired color tone.

Next, one embodiment will be described based on the drawings. Materials such as iron 1
is hung on the hanger 2 of the automatic feeder a.

As the first process hanger 2 descends, the material 1 is immersed in the copper plating solution 3.

After copper plating is applied, the hanger 2 rises and moves. As the second process hanger 2 descends, it is washed with water 8.

Third step As shown in FIG. 2, the hanger 2 is moved up and down to apply bronze coloring.

That is, the material 1 is immersed in the bronze solution 4 for the first time within 30 seconds, then pulled up and left in the air for the same period of time. Next, material 1 is immersed in the second bronze solution 4 for less than 30 seconds,
It is lifted up and left in the air for the same amount of time.

Furthermore, it is immersed in bronze solution 4 for an appropriate time to obtain a desired black tone.

Fourth step: After the bronze coloring, the bronze is washed with water 5 and hot water 6 containing a discoloration preventive agent and a cutting agent.

Fifth step: Drying 7 is performed.

However, in the first step, a copper plating paste 3 is applied to a material 1 such as iron.
Copper plating is applied in the second step, followed by water washing in the second step.

Next, there are two hangers 4a and 4b in the bronze solution 4. The first hanger 4a is dipped in a bronze solution 4 for uniformity and better fixing.
A is equipped with a lifting and lowering device for raising the ship once or twice in the air. The second hanger 4b is
In order to adjust the color tone, a speed-up device is provided to shorten the immersion time in the bronze solution 4 for light black colors and to lengthen the immersion time for deep black colors. In the third step, the conventional 1
The multiple dipping method causes color unevenness and poor adhesion, but in the present invention, the chemical reaction shown in the formula below occurs, so that unlike conventional methods, color unevenness does not occur and the colored state becomes uniform. .

CU+K2S+02 That is, by carrying out the coloring reaction in the bronze solution 4 and the oxidation reaction in the air, the coloring reaction is suppressed, and this phenomenon suppresses the local sulfurization reaction.
Because the sulfurization reaction occurs uniformly over the entire surface, no discoloration occurs.

As such, the present invention has the following features.

(1) In the present invention, the automatic copper plating process and the automatic bronzing process can be combined, eliminating the conventional manual process based on experience, and automatically adjusting the concentration of the bronzing solution 4 and the immersion time and number of times. This enabled mass production with uniform quality.

(2) The material 1 after copper plating is pre-treated by dipping once or twice for a short period of time in order to create a uniformly colored base in the bronze solution 4, and after the pre-treatment, dipping is performed to adjust the color tone. By carrying out the pre-treatment, the coloring reaction is carried out in the bronze solution and the oxidation reaction is carried out in the air, thereby suppressing the coloring reaction.This suppression suppresses the local sulfurization reaction and improves the quality of the item. A uniform sulfurization reaction occurs over the entire surface, resulting in an excellent bronze color with no uneven coloring. (3
) As a known technique of the present invention, a copper plate is immersed in a colored liquid mixed with a sulfide such as potassium sulfide and permanganese oxide in a ratio of 75 to 8,801) to 25 to 12% and shaken. 27730, or by mixing a coloring liquid containing 2 to 20 g/t of a sulfide such as ammonium sulfide and a basic compound such as potassium hydroxide, and immersing a copper plate in this coloring liquid and shaking it slightly gently from time to time. Tokuko Sho 54, which is colored step by step when immersed in water for 30 seconds to 12 minutes.
A method for coloring copper is known as disclosed in Japanese Patent No. 864.

These conventional techniques involve one-time dipping, and the dipping time is adjusted to obtain the desired color. However, in the present invention, the process 1 of immersing the bronze liquid 4 within 30 seconds and leaving it in the air for the same amount of time is repeated once or twice. Because the method first forms an even colored adhesion layer and then immerses it again for an appropriate time to obtain the desired color tone, there is no risk of color unevenness, and the rate of defective products can be significantly reduced. Masu.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, with FIG. 1 being a process diagram and FIG. 2 being an explanatory diagram showing the immersion process in a bronze solution. 1...Material, 2...Hanger, 3...
...Copper plating paste, 4...Bronze liquid, 5...
...Water washing, 6...Hot water washing, 7...Drying, 8...Water washing, a...Ringing feed device,
4a...First hanger 4b...Second
Hanger.

Claims (1)

[Claims] 1. A bronze coloring method for copper in which copper is immersed in a bronze solution containing potassium sulfide as a main component to color the copper black,
After soaking for less than 30 seconds, the process of leaving it in the air for the same amount of time is 1.
Or, a method for bronze coloring copper, which is repeated twice and then immersed again for an appropriate time to obtain a desired color tone. 2. The bronze coloring method for copper according to claim 1, wherein the copper is plated on a material such as iron.