DE1146322B - Acid galvanic metal baths - Google Patents

Description

GERMAN

PATENT OFFICE

D35328VIb / 48a

REGISTRATION DATE: 2nd F E B RU AR 1961

NOTICE THE REGISTRATION AND ISSUE OF THE EDITORIAL: MARCH 28, 1963

It has been found that organic sulfonic acids or their salts, which in the molecule at least have a thiourea and at least one dithiocarbamic acid residue, in acidic galvanic Metal baths, especially galvanic copper baths, at the same time excellent gloss-giving and develop leveling properties.

Up to now, such effects could only be achieved through a combination of different glossing and leveling agents achieve, which often also have other additives, such as anti-pore, leveling, Wetting agents and / or agents to increase the temperature tolerance, require.

The use of the agents according to the invention is therefore a significant simplification of the Baths can be achieved while improving the quality of the metal coatings. Own these products excellent high-gloss and strong leveling properties, with one that is practical for everyone Needs sufficient temperature tolerance, so that with their help the manufacture and Maintenance of galvanic metal baths, especially high-performance bright copper plating baths, made much simpler. Except in galvanic copper baths in which the aforementioned sulfonic acids or their salts have a particularly remarkable effect, these can also be used to advantage in galvanic baths containing salts of the metals zinc, lead, tin and cadmium or their mixtures, can be used.

The sulfonic acids or their salts used according to the invention can be prepared by known methods manufacture in a simple manner. Generally they are characterized by at least one dithiocarbamic acid group the general formula

—S — C — N

\
SR ₁

in which R and Ri are hydrogen or hydrocarbon radicals mean. Such radicals are identical or different alkyl radicals, which may be substituted or together with the inclusion of the nitrogen atom Acid galvanic metal baths

Applicant:

Dehydag, Deutsche Hydrierwerke
G. mb H., Düsseldorf, Henkelstr. 67

Dr. Wolf-Dieter Willmund, Düsseldorf-Holthausen,

Dipl.-Ing. Gregor Michael

and Dr. Alfred Kirstahler, Düsseldorf,

have been named as inventors

heterocyclic ring, such as ζ. B. can form a morpholine or piperazine ring, or cycloalkyl radicals.

Furthermore, the sulfonic acids used are characterized by at least one thiourea group the general formula

R ₂

R ₃

R ₂

N — C —NH- resp.

N-C = NH

R ₃

in which R ₂ and R _{3 are} hydrogen, alkyl radicals, cycloalkyl radicals, optionally substituted aryl radicals or also dithiocarbamic acid radicals bonded via an acyclic or cyclic intermediate member, as already described above.

Finally, the sulfonic acids have an alkyl sulfonic acid group the general formula

-R ₄ -SO ₃ H,

in which R _{4 represents} a low molecular weight alkyl radical Ci to C4.

Sulfonic acids or their sodium salts of the type used according to the invention are, for example Disodium salt of l-phenylthioureido-3,6-diazahexamethylene - 3,6 - bis - (dithiocarbamic acid - propylester-ci) -sulfonic acid) the formula

-NH - C - NH - CH ₂ - CH ₂ - N - CH ₂ - CH ₂ - NH - C - S - (CHa) ₃ SO ₃ Na (1)

= C - S (CH ₂ ) ₃ -S0 ₃ Na

309 547/335

which from diethylenetriamine and phenyl mustard oil to form the N-phenyl-N'-3,6-diaza-hexylthiourea and its further reaction with carbon disulfide and propane sultone as described below Way is obtained.

To a solution of 0.5 mole of diethylenetriamine in 300 cm ³ of ethanol is allowed to 0.5 mol of phenyl isothiocyanate at 30 to 35 ⁰ C are added dropwise and stirred for 2 hours. 1 mol of sodium hydroxide, dissolved in 150 cm ^{3 of} water, is added, and 1 mol of carbon disulfide is further added dropwise at 40 ° C. to the solution. The mixture is stirred for 20 minutes under temperature increase to 6O ⁰ C and then allowed to 1 mole of molten propane sultone added dropwise.

After a few hours of refluxing, the mixture is concentrated in vacuo. The sulfonic acid obtained Salt is triturated with acetone, filtered off, washed with acetone and dried in vacuo. There are 232 g

(= 60% of theory) sulfonic acid salt in the form

of a yellowish powder that works well in water

is soluble, has no melting point and is

gradually decomposes when heated above 200 ° C.

As another example of the invention

ίο sulfonic acids is 4-thiohexahydro-1,3,5-triazinyl-1 - ethyldithiocarbamic acid - propyl ester - ω - sulfonic acid

S = C

NH'-CH ₂

NH-CH ₂ N - CH ₂ - CH ₂ - NH - C - S - (CHs) ₃ - SO ₃ H

to call. The sodium salt of this sulfonic acid is obtained by condensation of the sodium salt the Aminoäthyldithiocarbamic acid - propyl ester co-sulfonic acid with thiourea and formaldehyde in good yield as a yellowish, non-melting powder.

As an example of a group of compounds in which a propanesulfonic acid group via the in the isoform present is bound thiourea, the reaction product of the sodium salt is the 2 - Thioimidazolinyl - N - äthyldithiocarbamic acid propyl ester-cü-sulfonic acid to name with propane sultone. The sulfonic acid mentioned is formed in the manner indicated above from 2-thioimidazolinyl-N-ethylamine, Carbon disulfide and propane sultone in the presence of one equivalent of sodium hydroxide solution. That obtained condensation product corresponds to the following formula:

H ₂ C CH ₂

N - CH ₂ - CH ₂ - NH - C - S - (CHs) ₃ SO ₃ Na

HN

S- (CHs) ₃ SOs

Further, sulfonic acids or their salts comparable _40, the reaction product of N, N'-bis (diäthylthiowendbar where Dithiocarbaminsäuregruppe carbamyl-mercaptomethy ^ -thioharnstoffs with Proüber a Esterbindung with the thiourea and the sulfonic acid-containing moiety

pansulton, which has the following formula:

connected is. An example of such a substance is

C ₂ H ₅

C ₂ H ₅

N-C-S-CH ₂ -NH-C = NH-CH ₂ -S-C-N

S - (CH ₂ ) ₃ SOi

C ₂ H ₅

C ₂ H ₅

The bond between the dithiocarbamic acid residue and the thiourea residue, which in the case of the Compound (No. 4) described above is formed from a methylene group can also be formed by other groups take place, e.g. B. by an ethylene or propylene group or by another short-linked hydrocarbon radical which is optionally substituted or interrupted by heteroatoms or with the inclusion of the two nitrogen atoms to form a heterocyclic ring, e.g. B. Piperazine, may be closed.

The alkylsulfonic acid residues are bound in the molecule via sulfur or nitrogen and are preferably introduced into the dithiocarbamic acid and / or thiourea residues. On the combination of these leftovers is based on the special high-gloss and leveling effect of the products according to the invention. To the Further explanation of suitable sulfonic acids are the following compounds with the for the cite characteristic groupings of products according to the invention.

C ₂ H ₅

NH-C = NH-CH ₂ -SCN

Il \

S - (CH & SOs SC ₂ H ₅

5 6

CH ₃ CH ₃

NCS-CH ₂ -NH-C = NH-CH ₂ -SCN (6)

/ Ii ι Ii \

CH ₃ SSS CH ₃

(CHa) ₃ SOi

CH ₂ -CH ₂ CH ₂ -CH ₂

CH ₂ NCS-CH ₂ -NH-C = NH-CH ₂ -SCN CH ₂ (7)

\ / Il I Il \ /

CH ₂ -CH ₂ SSS CH ₂ -CH ₂

(CHa) ₃ SOi

H ₂ NC-NH-CH ₂ -SC-NH-CH ₂ -CH ₂ -CH ₂ -SO ₃ Na SS

/ V-NH-C-NH-CH ₂ -CH ₂ -NH- (CH ₂ ^ -NH-CS- (CHa) ₂ -SO ₃ Na (9) \ = / II II

CH ₂ - CH ₂

NaO ₃ S- (CHa) ₃ -N

NCS-CH ₂ -,

CH ₂ - CH ₂ S

CH ₂ - CH ₂

C = NH-CH ₂ -SCN N- (CH ₂ ) SSO ₃ Na

I Il \ /

SS CH ₂ CHa

(CHa) ₃ SO ₃ "

/ ^ -NH-C-NH-CH ₂ -CH ₂ -N-CH ₂ -CH ₂ -NH-CS- (CH ₂₎ SSO ₃ Na (11) S (CHa) ₃ S

SO ₃ Na

NH-C-NH-CH ₂ -CH ₂ -NH-CS- (CH ₂ ) ₃ - SO ₃ Na (12)

S S

CH ₂ -N-

-CH ₂ -

CH ₂ -

■ N - CH ₂ - CH ₂ - NH- C - NH- «

= CS (CHa) ₃ SO ₃ Na S = CS (CH ₂ ) SSO ₃ Na (13)

It was also found that sulfonic acids, which contain aromatic radicals in the molecule, such as z. B. phenyl, tolyl, xylyl, naphthyl, diphenyl radicals etc., particularly cheap gloss-giving, strong leveling, good leveling and in many cases network properties also have sufficient temperature tolerance for all practical needs, so that they produce a one-component bath, at least if their Property as a wetting agent is not sufficiently pronounced, that of a two-component bath enable.

The agents according to the invention are the galvanic Baths in amounts of 50 mg to 5 g / l, preferably in amounts of 100 to 500 mg / l, Bath liquid added. The application of the funds does not require any special measures, they are in the acidic metal salt baths in the required

Amount easily soluble and show good resistance even during the electroplating operation. she can, if necessary, also be used in combination with other known electroplating chemicals will.

example 1

To an acidic copper plating bath containing 210 g / l copper sulfate CuSO ₄ · 5 H ₂ O, 80 g / l sulfuric acid, 2 g / l of the adduct of 18 mol of ethylene oxide with 1 mol of nonylphenyol, 0.25 g / l Ν, Ν, Ν ', Ν'-Tetraethyl-1,3-diaminopropanol-2, 0.2 g / l of compound no. 4 are added. This bath composition provides uniformly high-gloss and well-leveling copper coatings in the current density range from 0.3 to 8 Amp./dm ² and with a temperature tolerance of 10 to 38 ° C. The copper coatings are ductile and pore-free. With a thickness of 20 μ, they completely level a 280 grain joint without any further additives.

Example 2

To an acidic copper plating bath containing 210 g / l copper sulfate CuSO ₄ · 5 H ₂ O, 60 g / l sulfuric acid, 1 g / l of the adduct of 20 mol of ethylene oxide with 1 mol of a coconut fatty alcohol mixture, 0.02 g / l thioflavine add 0.1 g / l of compound no. 8.

This bath composition provides ductile, pore-free, uniformly high-gloss and well-leveling copper coatings in the current density range of 0.2 to 8 amps / dm ² with a temperature tolerance of 10 to 38 ° C. A 280-grain grinding is achieved by a 20 μ thick copper layer without any further additives completely leveled.

Example 3

If the bath composition is otherwise the same as in Example 2, it is used as a gloss and leveling agent 0.1 g / l of compound no. 7 results in the same good results as in example 2.

Example 4

To an acidic copper plating bath containing 220 g / l copper sulfate CuSO ₄ ■ 5 H ₂ O, 60 g / l sulfuric acid, 1 g / l of the adduct of 18 mol of ethylene oxide and 1 mol of nonylphenol, 0.20 g / l of compound no 2 given.

It is not necessary to add another component. The copper coatings obtained are ductile, pore-free, have a uniform high gloss and a good leveling effect in the current density range from 0.2 to 8 amps / dm ² and with a temperature tolerance of 10 to 38 ° C. A 250 grain joint is completely leveled by a 20 μ thick copper layer.

If the bath described is operated without the addition of a wetting agent, equally good results are obtained with regard to the quality of the copper coatings, but preferably in the somewhat narrower current density range of 1.5 to 8 amps / dm ² . acid, 1 g / l of the adduct of 20 mol of ethylene oxide with 1 mol of a coconut fatty alcohol mixture, 0.10 g / l of compound no. 3 is added. No further component is required. The result is ductile, pore-free, uniformly high-gloss and well-leveling copper coatings in the current density range from 0.5 to 10 Amp./dm ² and with a temperature tolerance of 10 to 38 ° C. A 280 grain joint is completely leveled by a 20 μ thick copper layer.

Example 6

0.5 g / l of compound no. 1 is added to an acidic copper plating bath containing 210 g / l copper sulfate CuSO ₄ · 5 H _{2 O, 60 g / l sulfuric acid.}

The addition of further aids is not necessary, as this simple bath composition already provides ductile, pore-free, uniformly high-gloss and well-leveling copper coatings in the current density range from 0.5 to 8 amps / dm ² , with a temperature tolerance of 10 to 35 ° C. A 220 -Grain cut is completely leveled by a 20 μ thick copper layer. Another advantage of this bath is that it can be operated with air without difficulty.

Example 7

0.4 g / l of compound no. 5 is added to an acidic copper plating bath containing 210 g / l copper sulfate CuSO ₄ · 5 H _{2 O, 60 g / l sulfuric acid.}

The addition of a further component is not necessary in this case either. The result is ductile, pore-free, uniformly high-gloss and well-leveling copper coatings in the current density range from 0.5 to 8 Amp./dm ² and with a temperature tolerance of 10 to 35 ° C. A 220 grain joint is completely leveled by a 20 μ thick copper layer. This bath can also be operated with air in an advantageous manner.

Example 8

To an acidic galvanizing bath containing 300 g / l zinc sulfate, 10 g / l aluminum sulfate, 20 g / l boric acid, 0.15 g / l of compound no. 5 is added. The bath is operated in a pH range between 3 and 5 and delivers shiny, ductile, very fine-grained zinc precipitates that adhere well to the iron surface in the current density range of 0.5 to 8 amps / dm ² with a temperature tolerance of 15 to 30 ° C .

Example 9 Example 5

To an acidic copper plating bath containing 210 g / l copper sulphate CuSO ₄ ■ 5 H ₂ O, 60 g / l sulfur-An acidic copper plating bath containing 210 g copper sulphate CuSO ₄ -5 H ₂ O, 60 g sulfuric acid and 8 g per liter bath liquid of an attachment

Product of 8 moles of ethylene oxide and 1 mole of a coconut fatty alcohol mixture, when 20 to 80 mg of compound no.13 is added per liter of bath liquid, it produces ductile, pore-free, uniformly high-gloss and well-leveled copper coatings in the current density range from 0.5 to 8 amps. dm ² with a temperature tolerance of 10 to 35 ° C. A 320 grain joint is completely leveled by a 20 μ thick copper layer.

If the bath described is operated without the addition of a wetting agent, the result is equally good Results in terms of the quality of the copper plating when the added amount of the compound No. 13 is increased to 200 mg / 1 bath liquid.

Claims (4)

PATENT CLAIMS: 1. Acid baths of conventional composition with a content of organic sulfonic acids for the production of galvanic metal coating, characterized in that they contain such organic sulfonic acids or salts thereof, which have a Dithiocarbaminsäurerest in the molecule at least one and at least ThioharnstofFrest. 2. Baths according to claim 1, characterized in that they contain organic sulfonic acids or whose salts contain which have at least one aryl radical in the molecule. 3. Baths according to claim 1 and 2, characterized in that they contain organic sulfonic acids or contain their salts, whose sulfonic acid residue is in the form of an alkylsulfonic acid residue via the Sulfur atom of the thiourea residue is bound. 4. Baths according to claim 1 to 3, characterized in that they contain the organic sulfonic acids or their salts in an amount of 50 mg to 5 g, preferably 100 to 500 mg / l, Bath liquid included. © 309 547/335 3.63