DE1030133B - Process for the production of galvanic copper coatings - Google Patents

Description

GERMAN

The subject of the main patent 1 000 204 is a method for producing galvanic copper coatings with the special feature that acid electroplating copper baths are used before or during electroplating in addition to bright electroplating agents, carboxyl group-free amino compounds of the general formula

R ₁

R ₃

Method of manufacture
galvanic copper coatings

Addendum to patent 1 000 204

R ₂

R ₄

adds, in which X is a divalent acyclic or cyclic hydrocarbon radical or together with one or both nitrogen atoms a heterocyclic ring system which contains no further heteroatoms apart from these nitrogen atoms and R ₁ , R ₂ , R ₃ and R _{4 are} hydrogen or a hydrocarbon radical, where the Hydrocarbon radicals can also contain heteroatoms or heteroatom groups or substituents.

By adding the compounds of the main patent to electroplating baths it is achieved that inorganic Impurities such as B. in the hardness components of the water, as well as in metal salts of technical quality, have no adverse effect on the properties of copper coatings which are made using made of brighteners. The compounds mentioned also have the property of ductility to increase galvanic coatings.

It has now been found in a further development of this process that sulfonic acid can also be used with particular advantage. or sulfuric acid ester derivatives of such carboxyl group-free amino compounds of the above May use formulas that contain one or more sulfonic acid groups or sulfuric acid ester groups, which can optionally be in the form of their salts with inorganic or organic bases.

Connections of this type are for example:
N-ethyl-N-ß-aminoethyl-aminoethanesulfonic acid,
N, N-diethyl-ethylenediamino-N ', N'-bis- (ethane-

sulfonic acid),

1,3-diaminopropane-2-sulfonic acid,
N, N, N ', N'-Tetra-n-butyl-1,3-diaminopropanol

2-monosulfuric acid ester,
Piperazine-N, N'-bis- (2-oxypropanesulfonic acid),
2,5-diaminobenzene-l-sulfonic acid,
2,5-diaminobenzene-1,4-disulfonic acid

as well as further sulfonic acid or sulfuric acid ester derivatives of the compounds mentioned in the main patent. These additives ensure that the brighteners in baths containing impurities over the entire period effective current density range lead to perfect copper luster deposits. Beyond that Applicant:

DEHYDAG

Deutsche Hydrierwerke GmbH,
Düsseldorf, Henkelstr. 67

Dr. Wennemar Strauss and Dr. Wolf-Dieter Willmund,

Düsseldorf-Holthausen,
have been named as inventors

the additives mentioned were absorbed by the galvanic metal coatings to a much lesser extent than the corresponding connections of the main patent, which results in a more economical consumption.

The conditions of use largely correspond to those of the main patent with regard to the required application rates, working temperatures, etc. For example, the application concentration of the agents according to the invention is between 0.01 and 15 g / l bath liquid, preferably between 3 and 12 g / l. In general, electroplating is carried out at temperatures from 20 to 60 ° C. using current densities between 0.5 to 15 amp./dm ² .

Examples

1. An acidic copper bath containing 200 g / l technical copper sulphate, 60 g / l concentrated sulfuric acid and as Rinse aid 1.2 g / l l, 3,5-triazine-2,4,6-tris- (mercapto-2-oxypropanesulfonic acid) or contains its sodium salt, is used to render harmless the substances contained in the bath Impurities 2 g / l piperazine-N, N'-bis- (2-oxypropanesulfonic acid) or their sodium salt. The copper coatings on iron that can be produced in this bath, Iron alloys etc. turn out to be high-gloss. If you work without the addition of piperazine-N, N'-bis- (2-oxypropanesulfonic acid), all other things being equal, one only achieves less shiny copper deposits.

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2. If an acidic copper bath is added, which contains 250 g / l technical grade copper sulfate, 70 g / l concentrated sulfuric acid and 0.3 g / l Ν, Ν-diethyl-ditMocarbamic acid-ethyl ester-ct> -sulfonate-acid sodium as a brightener 1.5 g / l N.NjN'.N'-tetra-n-butyl-IS-diaminopropanol-2-monosulphuric acid ester, high-gloss copper precipitates are obtained in the electroplating of cyanidically pre-coppered iron sheets. The best copper coatings are obtained when working at 25 ° C and with current densities between 1 and 6 Amp./dm ² . If you work without the addition of 1.5 g / l Ν, Ν, Ν ', Ν'-tetra-n-butyl, 3-diaminopropanol-2-monosulphuric acid ester, only the current density range of 2 to 3 amps / dm ^{2 occurs} usable gloss effect.

3. Particularly good gloss effects are achieved if a copper bath made with 180 g / l copper sulfate and 90 g / l concentrated sulfuric acid with 0.3 g / l 1,3,5-triazine-2,4,6-tris- ( mercapto-2-oxypropanesulfonic acid) and 0.1 g / l NjN-diethyl-dithiocarbamic acid ethyl ester-casulfonic acid sodium as a brightener and 1 g / l 2,5-diaminobenzene-1,4-disulfonic acid is added. At temperatures between 20 and 45 ° C, current densities of up to 13 Amp./dm ^{2 can be} electroplated. Without the addition of 2,5-diaminobenzene-1,4-disulfonic acid, the copper precipitates are less shiny.

Claims (1)

Claim: Process for the production of galvanic copper · || Coatings with the addition of bright electroplating: || agents and carboxyl ^{Aminoverbmdun-:} äly gen of the general formula R ₃ Ν — Χ —Ν ' .., ijili in which X is a divalent acyclic acyclic hydrocarbon radical or, together with one or both nitrogen atoms, a heterocyclic ring system which, apart from these nitrogen atoms, contains no further heteroatoms and Rj R ₂ , R ₃ and R ₄ denote hydrogen or a hydrocarbon radical, the Hydrocarbon radicals can also contain heteroatoms or heteroatom groups or substituents, according to Patent 1 000 204, characterized in that the amino compounds free of carcoxyl groups are those which contain one or more sulfonic acid groups or. Sulfuric acid ester groups, optionally in a salt-like bond with inorganic or organic base formers. © 809 510/434 5.58