RU1801966C - Polydisulfide of cyanuric acid as additive for chemical nickel plating - Google Patents

Abstract

Appointment -. additive in a solution of chemical nickel plating Cyanuric acid polydisulfide o-c c-o-s-s- II I OHJ / i where n 1b-18 „1 scoreboard

Description

The invention relates to the chemistry of sulfur-containing compounds that can be used as additives in chemical nickel-plating solutions containing sodium hyophosphite as a reducing agent

There are many additives in chemical nickel-plating solutions that stabilize or change the speed of the process. For example, thiourea, sodium thiosulfate, a complex additive including sulfosalicylic acid in combination with triethanolamine, accelerating the nickel deposition process

However, known sulfur-containing additives have a significant effect on the catalytic activity of the TiO - system, poisoning the catalytic centers at the initial stage of the reaction (during the induction

period), as a result of which there is an increase in the induction period for the formation of solid phase particles, as well as a decrease in their growth rate in the volume or complete poisoning of the catalytic surface. The use of a mixture of sulfosalicylic acid with triethanolamine as an additive in hypophosphate solutions of nickel plating has significant drawbacks when used for TiOa - pd1 system, the specificity of this system-1 is that the pH of the chemical nickel plating solution should lie in the range from 6 to 7 at a temperature e precipitation 50-65 ° C due to the impossibility of producing nickel-plated coating with satisfactory adhesion under more stringent (6 pH 7) conditions plating, additives that restricts

ate with

00

about

Yu

oh oh

The aim of the invention is to increase the speed of the deposition process from aqueous solutions of chemical nickel plating on dielectric substrates (glass, ceramic, polyimide, lavsan and dro)

This goal is achieved in that as an accelerating additive in chemical nickel plating solutions, cyanuric acid polydisulfide of the general formula (1

-o-c c-0-s-s-

HE

It

where n is 8-1b0

These polysulfides and the method for their preparation are not described in the literature /

Cyanuric acid polydisulfide is obtained by condensation of a monomer of cyanuric acid with sulfur monochloride with

Example U 12.9 g of cyanuric acid (0.1 mol) was placed in a reaction flask, 150-200 ml of previously dried o-, m-, p-xol and 13.5 g of sulfur monochloride were added with vigorous stirring (0, 1 mol) for 20-25 minutes and then the reaction mass is heated at 110-120 ° С until the evolution of hydrogen chloride is completely stopped. After the completion of the reaction, the precipitate of cyanuric acid polydisulfide is filtered off, washed with o-, m-, p-xylene, then with distilled water before a negative reaction to a chlorine ion (Bernstein test) 0 Synthesis time 83 hours,, yield ucta 66.9 Mact% ,, The resulting cyanuric acid polydisulfide is a light yellow powdery substance 4BeTat

Identification of the chanted cyanuric acid polydisulfide obtained by us was carried out.

Elemental composition:

Calculated,%: C 18.85, H 0.52,

Found,%: C 19.18, H 0.48 „.

Infrared absorption spectrum, cm:

-S-S-450 J80

0

5

0

5

0

5

about

5

fifty

55

 - OH polymer 2980-3100 Molecular mass (Rast cryoscopy in diphenyl) - 2300t

A solution of chemical nickel plating is preliminarily prepared, the required amount of nickel chloride is completely dissolved in 500 ml of distilled water, sodium hypophosphite, ammonium chloride are added and the solution is stirred until the components are completely dissolved0 In a small amount of distilled water, cyanuric acid polydisulfide is dissolved, then while stirring is poured into the initial solution. The volume of the nickel-phosphorus coating chemical precipitation solution is adjusted to 1 liter with deionized water.

Evaluation of the effectiveness of cyanuric acid polydisulfide was carried out according to the following procedure:

Example 1 (blank experiment) 0 On a glass plate, cleaned from contamination by a known method, including, for example, treatment with chrompeak, alkaline emulsion of surfactants, washing in deionized water and the final stage of cleaning in isopropanol vapors, h applied t by irrigation, a composition containing (weight 0%): polybutyl titanate - 2, palladium chloride - 0.02, 10% hydrochloric acid solution - 0.5, isopropyl alcohol - 97.8 and dried at 120 ° C within 3 minutes 0 Then a plate with the resulting palladium hydride chloride doped film titanium oxide, whose thickness was 0.01 μm, is treated in a 1.5 M aqueous iso-propanol (1: 1) sodium hydrogen phosphite solution for 1 minute and chemically nickelized at 50 ° C for 5 minutes in solution containing, g / l:

Nickel chloride 15 Sodium acetate 10 Ammonium chloride 50 Sodium carbonate 2 Sodium hypophosphite 30 Solution temperature 50 ° C + 0.5 pH 6.9

After nickel plating, the plates are washed in deionized water, dried with warm air and heated in vacuo (133-665 Pa) with adjustable skog

heating rate (1-2 deg / min) at a temperature of 350 C for 30 min. Example 2 Everything is as in example 1, however, cyanuric acid polydisulfide is additionally added to the composition of the chemical nickel plating solution to increase the nickel deposition rate in the following ratio components, g / l: Nickel chloride 15 Sodium acetate 1 О Ammonium chloride 50 Sodium hypophosphite 30 Cyanuric acid polydisulfide 0.2 Solution temperature 50 ° С +0.5

pH 6.5.

Nickel precipitation is carried out immediately after preparation of the solution. The results are shown in table. 10

Example Zo Everything is the same as in example 2, however, nickel deposition is carried out from the solution 3 days after preparation o The data obtained are shown in the table

Example k0 Everything is as in example 2, however, precipitation, nickel is carried out from the solution 6 days after its preparation. The results are shown in the table

Example 5 ° All as in example 2, however, the precipitation of nickel is carried out from a solution of the following state, g / l:

Nickel Chloride 5

Sodium Acetate 5

Ammonium Chloride 25

Sodium hypophosphite 10

Poly disulfide cya.

Nuric acid T

Precipitation temperature + 0.5

pH 6.6

The nickel-plating solution of the wire is indicated above, however, the content of the components is reduced to the minimum value. The results are shown in the table. It should be noted that with this composition of the solution of chemical deposition of nickel, the rate of the deposition process sharply decreases in comparison with the optimal composition of the solution

Example 6 “Everything is as in example 2, however, the content of the components is increased to the maximum value, g / ls

Nickel chloride 20 Sodium acetate 20 Ammonium chloride 100 Sodium hypophosphite 60 Cyanuric acid polydisulfide 2 Precipitation temperature 50 ° C + 0.5 pH 6.6

The data are shown in the table. An increase in the concentration of components higher than that indicated in Example 6 leads to an increase in the rate of deposition of nickel, however, the stability of the solution decreases sharply

Example 7 Bces as in example 1, however, the nickel-phosphorus coating deposition is carried out 3 days after preparation of the nickel-plating solution. The data are shown in the table. It should be noted that the deposition rate of the nickel-phosphorus coating during storage of the (empty) solution is reduced by 25%

Example 80 Everything, as in example 1, but sodium carbonate was excluded from the composition of the solution. The data are shown in the table. The deposition rate from a blank solution is comparable to the deposition rate in example 80.

As follows from the above examples and the data in the table, the additional introduction of cyanuric acid polydisulfide leads to an increase in the deposition rate of the nickel-phosphorus alloy by 3-5 times while maintaining the deposition temperature and pI of the solution0 Note that the stability of the solution increases up to 6 days

Claims (1)

The claims Cyanuric Acid Polydisulfide Formulas rO- vN C-0-S-SH he J / i where n is 8-16, as an additive in chemical kelirovanie „ 0.2 0.2 0.2 1 50 ° C ± 0.5 in all examples 2, 7.1 7.7 8.0 5.5 1 thirteen 2, t 1.8  Nickel-phosphorus alloy deposition was carried out from a nickel chemical precipitation solution 3 days after the solution was prepared  The deposition of the Nickel-phosphorus alloy was carried out from a solution of chemical deposition of Nickel after 6 days after preparation of the solution