DE1134258B - Acid galvanic nickel bath - Google Patents

Description

The present invention relates to the galvanic production of shiny and leveling nickel coatings of good ductility and adhesion and deals in particular with the improvement of the gloss depth scattering in galvanic nickel baths.

It is known to use electrolytic nickel baths, brighteners such as sulfonamides, sulfonimides (saccharin), disulfonimides or to add a sulfo group-containing urea derivative. It is also known to increase the gloss and to achieve leveling effects three times in addition to the means listed above unsaturated alcohols, such as. B. butynediol, or pyridine or. Quinoline derivatives in bright nickel baths too use. However, it can often be observed that baths containing the above organic compounds included, in the low current density ranges (e.g. 0.25 to 0.5 Amp./qdm) or in these Areas of the perforations of the object to be vemikkelte matt or veiled nickel coatings appear. It can be seen that the strength of the fog depends on the speed the movement of goods in the nickel bath is dependent. Strong veils appear when goods move at 20 cm / sec in the low current density range, fogging can be reduced by half at 10 cm / see and be completely suppressed in the movement of goods zero. Since, however, when operating technical baths In most cases it is not possible to dispense with a movement of goods and also the speed the movement of goods differs from case to case, the monitoring of the baths is on Difficult because of the different intensity of the appearance of matt or hazy zones.

It has now been found that one can prevent the occurrence of dull zones in the low current density range, make the nickel plating process independent of the speed of the movement of goods can and particularly good gloss and leveling effects can be achieved if you use the nickel baths N-sulfonylcarboxamides of the type

R - CO - NH - SO ₂ - R '

together with salt-like reaction products from tertiary mononuclear or polynuclear heterocyclic Aromatic type nitrogen bases and sultones combined, e.g. B. the inner salt of pyridinium-N-propane-co-sulf onic acid or similar compounds of this type. In the formula are R and R ' for aryl or alkyl radicals, which can be identical or dissimilar. Both radicals can have substituents such as chlorine, bromine, hydroxyl groups, other alkyl radicals and others. Furthermore, the group Acid galvanic nickel bath

Applicant:

Dehydag Deutsche Hydrierwerke G.m.b.H., Düsseldorf, Henkelstr. 67

Dr. Wennemar Strauss, Düsseldorf-Holthausen, Dipl.-Ing. Gregor Michael, Düsseldorf,

and Dr. Wolf-Dieter Willmund,

Düsseldorf-Holthausen, have been named as the inventor

-CO-NH-SO ₂ -can also be present several times in the molecule.

Means according to the formula are z. B .:

N- (benzenesulfonyl) benzoylamide

C ₆ H ₅ - CO - NH - SO ₂ - C ₆ H ₅ N- (benzenesulfonyl) -p-toluylamide

CH ₃ - C ₆ H ₄ - CO - NH - SO ₂ - C ₆ H ₅ N-Cp -toluenesulfonylI-p -toluylamide

CH ₃ -CeH ₄ -CO-NH-SO ₂ -C ₆ H ₄ -CH ₃ N- (benzenesulfonyl) acetamide

CH ₃ - CO - NH - SO ₂ - C ₆ H ₅ N- (octylsulfonyl) acetamide

CH ₃ - CO - NH - SO ₂ - C ₈ H ₁₇ N- (benzenesulfonyl) -2-ethyl-hexanoic acid amide

C ₇ H ₁₅ - CO - NH - SO ₂ - C ₆ H ₅ N- (butylsulfonyl) -p-toluylamide

CH ₃ - C ₆ H ₄ - CO - NH - SO ₂ - C ₄ H ₉ N- (benzenesulfonyl) lauroylamide

C ₁₁ H ₂₃ - CO - NH - SO ₂ - C ₆ H ₅ N- (3,4-dichlorobenzenesulfonyl) -p-toluylamide

CH ₃ -C ₆ H ₄ -CO-NH-SO ₂ -C ₆ H ₃ -Cl ₂ N- (benzylsulfonyl) -p-toluylamide

CH ₃ -C ₆ H ₄ -CO-NH-SO ₂ -CH ₂ -C ₆ H ₅ N- (cyclohexylsulfonyl) benzoylamide

C ₆ H ₅ - CO - NH - SO ₂ - C ₆ H ₁₁ N- (benzenesulfonyl) butylamide C ₃ H ₇ - CO - NH - SO ₂ - C ₆ H ₅

209 628/242

N, N'-bis (p-toluenesulfonyl) -tartaric acid diamide

CH ₃ -C ₆ H ₄ -SO ₂ -NH-CO- (CHOH) ₂ -CO-Nh -SO ₂ -C ₆ H ₄ -CH ₃

N, N'-bis (xylenesulfonyl) adipic acid diamide

(CH ₃ ) ₂ - C ₆ H ₃ - SO ₂ - NH - CO - (CHj) ₄ - CO - NH - SO ₂ - C ₆ H ₃ - (CH ₃ ) ₂

m-Benzene-disulfonyl- (N, N'-di-lactyl) -amide

CH ₃ -CHOH-CO-NH-SO ₂ -C ₆ H ₄ -SO ₂ -NH-CO-CHOh-CH ₃

To suppress the formation of pores, small amounts of haloalkanesulfonic acids, like S-chloro - ^ - oxypropanesulfonic acid, 2-Bromoethanesulfonic acid, or other compounds of this type or their salts, as well as known ones Add wetting agent. The sole use of the above-mentioned agents in galvanic baths no protection is sought.

example 1

If one puts 1.5 g / l of N- (benzenesulfonyl) -benzoylamide, 0.35 g / l of the inner salt of pyridinium-N-propane-w-sulfonic acid and 1 g / l of the sodium salt of 3-chloro into a nickel bath of the Watt type -2-oxypropanesulphonic acid, high-gloss nickel coatings are obtained in the current density range from 0.1 to 8 amps / dm ^{2 at 55 ° C.} A matt zone formation in the low current density range is not recorded even with a goods movement of 20 cm / sec. If, however, the N- (benzenesulfonyl) -benzoylamide is exchanged for the sodium salt of toluenesulfamide, strong matt zones occur in the low current density range when goods move from 3.8 to 20 cm / sec.

Example 2

In one with 1.0 g / l of N- (benzenesulfonyl) -p-toluylamide, 0.8 g / l of the inner salt of quinolinium-N-propaneu-sulfonic acid, 1.2 g / l of the sodium salt of ω-oxypropanesulfonic acid and 0.5 g / l of sodium octyl sulphate, the nickel bath obtained is perfectly shiny at 50 ° C. in the current density range from 0.1 to 8 amps / dm ^2. If 1.5 g / l benzoic acid-4-sulfonamide is used instead of N- (benzene sulfonyl) -p-toluylamide, dull zones occur in the low current density range, especially at the edges of perforations.

Claims (3)

Patent claims: 1. Acid galvanic nickel bath of usual composition, characterized in that it non-cyclic N-sulfonylcarboxamides and salt-like reaction products from tertiary one or polynuclear heterocyclic nitrogen bases of the aromatic type and sultones. 2. Bath according to claim 1, characterized in that it contains non-cyclic N-sulfonylcarboxamides with several —CO — NH — SO ₂ groups in the molecule. 3. Bath according to claim 1 and 2, characterized in that it also contains haloalkanesulfonic acids or its salary contains. Considered publications:
German interpretative document No. 1 028 407. © 209 628/2 + 2 7.62