JPS6032719B2 - Nickel alloy plating liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the improvement of a nickel-phosphorus alloy plating solution suitable for application to surface treatments that require acid resistance, corrosion resistance, abrasion resistance, mold releasability, discoloration resistance, etc. .

Various nickel-phosphorus alloy plating solutions have been reported, and typical examples are shown below.

Example 1 NiS.

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H0.5-1.0 Liquid temperature 75-90ooExample 2 Nickel sulfate 250 t Sodium lactate 80 t/t Sodium hypophosphite 6 t/t 2.5-3.5 Liquid temperature 40-8 0 Example 3 Nickel chloride 40 t/so Nickel carbonate 40 t/t Nickel sulfate 160 t/sorinic acid
50 evenings/phosphorous acid
44th evening/SoPHO. 5-1.0 These conventional nickel-phosphorus alloy plating solutions contain multiple nickel salts or organic acid salts, and multiple phosphorus-containing chemicals are added, so when using them, it is important to Not only does plating cause a large loss and is a sterile agent, but also complicates the maintenance and management of the plating solution.

For this reason, the phosphorus content in the precipitate is easily fluctuated and unstable, the life of the plating solution is short, and after using the plating solution for a certain period of time, part or all of the plating solution must be replaced with a new plating solution. There were drawbacks such as: The present invention aims to improve the above-mentioned drawbacks of the conventionally used nickel phosphorus alloy plating solution, and it simplifies the composition contained in the plating solution and improves the quality of the plating solution and the pumping during use. The objective is to simplify the chemical replenishment involved, simplify the maintenance and management of the plating solution, stabilize the phosphorus content in the deposited film, extend the life of the plating solution, and provide a plating solution that can withstand long-term continuous use. It is.

As a result of repeated studies on nickel-phosphorus alloy plating solutions, the inventor found that it is not necessary to use multiple nickel salts, and that nickel sulfate alone is sufficient, and that phosphoric acid has the ability to adjust the pH of the plating solution and to dissolve into plating deposits. It was discovered that nickel sulfate and phosphorous acid have little precipitation effect, and that phosphorous acid alone is sufficient, while organic acid salts decompose during use of the plating solution, contaminating the plating solution and shortening the life of the plating solution. It has been found that a plating solution consisting of Next, examples of the present invention will be shown.

Example 1 An aqueous solution having the composition of nickel sulfate hexahydrate 230 t/s and phosphorous acid 40 t/s was subjected to PHI. with sodium hydroxide. A nickel phosphorus alloy deposited film with surface photo-selectivity was obtained by using a plating solution adjusted to 0 as a plating solution, a nickel plate as an anode, and a polished steel plate as a cathode at a plating solution temperature of 80° C. and a cathode current density of 2 A/d.

Example 2 An aqueous solution with the composition of 100% nickel sulfate hexahydrate and 10% phosphorous acid was prepared, and a nickel plate anode and an insoluble anode such as a stainless steel plate were used, a steel plate was used as the cathode, and the plating solution temperature was 80%. Electrolysis was performed at a cathode current density of 4 A/d,
The pH was set to 0.5.

Using this solution as a plating solution, plating was carried out under the same conditions as in Example 1 to obtain a deposited surface with few bits, roughness, and cracks, and an optically selective surface. Example 3 An aqueous solution with a composition of 100% nickel sulfate hexahydrate and 40% polyphosphorous acid was adjusted to pH 1.5 with nickel hydroxide as a plating solution, a nickel plate was used as an anode, and molded with vinyl chloride resin. Using the mold as a cathode, plating was carried out at a plating solution temperature of 75° C. and a cathode current density of 4 A/d to obtain a mold resistant to decomposition gas of pinyl chloride.

As shown in the above embodiments, the plating solution of the present invention has a simple composition of nickel sulfate hexahydrate and phosphorous acid;
When the nickel in the plating solution is released as a nickel-phosphorus alloy and the specific gravity of the plating solution decreases, nickel sulfate hexahydrate is added while measuring the specific gravity to keep the specific gravity constant, while phosphorus is precipitated as a nickel-phosphorus alloy. When the phosphorus content of the plating solution decreases, the phosphorus in the plating solution consists only of phosphorous acid, so the phosphorus in the plating solution is analyzed and the insufficient amount of phosphoric acid is replenished to maintain the phosphorus concentration. .

Bait management is easy by adding sulfuric acid. As described above, according to the present invention, nickel sulfate hexahydrate and box phosphoric acid are repeatedly replenished as much as they are deposited as nickel phosphorus alloy plating, and the phosphorus content is kept constant with little fluctuation and uniformity. The plating film can be obtained, the life of the plating solution is long, and there is no need to replace part or all of the plating solution with a new plating solution, which is highly effective.

Claims (1)

[Claims] 1. Adjust the pH of an aqueous solution consisting of 100 to 400 g/l of nickel sulfate hexahydrate and 10 to 40 g/l of phosphorous acid to 0.5 to 2.
．． A nickel phosphorus alloy plating liquid that maintains the temperature at 0.