DE2053860A1 - Acid galvanic copper bath - Google Patents

Description

SCHERING AG

Berlin, October 27, 1970

Acid galvanic copper bath

The invention relates to an acidic, aqueous electrolyte for the deposition of shiny, low-stress and ductile copper coatings.

It is known that acidic, in particular the most common sulfuric acid copper electrolyte -Add certain organic substances in small amounts in order to obtain shiny copper coatings instead of a crystalline matt deposit. Proposed were mainly organic thio compounds such. B. Thioalkanesulfonic acids (German Patent No. 1.037.801), derivatives of saurer sehwe-. containing phosphorus derivatives (German patents No. 1.168.208, No. 1.196.464, No. 1.201.152) and organic sulfides with at least one sulfonic acid in a mixture or in chemical bond with a polyether (German Offenlegungsschrift No. 1.521.062).

These thio compounds often have a negative effect on the functioning of the acidic electrolytes and the properties of the copper precipitates deposited therefrom. For example, the precipitation in 209824/1019 " ² "

SCHERINGAG

October 27, I97O

If current density ranges are black-streaked as a result of the formation of copper sulfide, or coatings with high hardness or high macro-residual stresses are deposited, which show poorer corrosion behavior, especially under mechanical loads. Many of the organic thio compounds are also very critical in their dosage and may only be added to the electrolyte in a very narrow concentration range if one wants to obtain coatings with constant properties.

The invention is therefore based on the object of preventing the formation of black-streaked precipitates and the deposition of shiny, low-stress and ductile copper precipitates with a high corrosion protection value over a wide area Allow current density range.

P This object is achieved according to the invention by an acidic, aqueous copper electrolyte which is characterized by a content of at least one compound of the general formula

R ₁ - (Se) _n - R ₂

in which R ₁ and R «are identical or different and represent an optionally mono- or polysubstituted aromatic, aliphatic, cycloaliphatic, araliphatic or heterocyclic hydrocarbon radical, where at least

• - 3 -209824/1019

Z U D J O D U Patent Department

- 3 - 'October 27, 1970

one of the two radicals contains a sulfonic acid group, or in the R, which has the aforementioned meaning and Rg the cyanide or the sulfonic acid group and η the number 1 or 2, or their salts.

Particularly suitable additives are those compounds in which, in the above general formula, R-, phenyl, nitrophenyl, Alkylphenyl, alkoxphenyl, carboxphenyl, carbmethoxphenyl, dimethylaminephenyl, alkylmercaptophenyl, aminophenyl, alkyl with preferably 2 to 8 carbon atoms, benzyl, phenoxyalkyl, Sulfolanyl, furyl, cyclohexylalkyl, pyridylalkyl, carboxyalkyl, dihydroxypropyl, sulfoalkyl with preferably 2 to 6 Carbon atoms, sulfophenyl, alkoxy-sulfophenyl, alkylmercapto-sulfophenyl, Halosulfophenyl, sulfonaphthyl, disulfonaphthyl or sulfopheiiyl-alkyl and Rg sulfoalkyl with preferably 2 to 6 carbon atoms, sulfophenyl, alkoxy-sulfophenyl, alkylmercapto-sulfophenyl, halogen-sulfophenyl, sulfonaphthyl, Disulfonaphthyl or sulfophenylalkyl and η die Numbers 1 or 2 represent or in which R ^ sulfoalkyl with preferably 2 to 6 carbon atoms, sulfophenyl, alkoxysulfophenyl, alkylmereapto-sulfophenyl, halosulfophenyl, sulfo - mphthyl, disulfonaphthyl, sulfophenylalkyl, Rg the cyanide or represent the sulfonic acid group and η is the number 1.

The compounds to be used according to the invention are per se known or can be produced by methods known per se, such as those in HOUBEN-WEYL "Methods of Organic

209824/1019 -4-

SCHERING AG

Patent department

- 4 - October 27, 1970

Chemie ", Volume 9 (1955), pages 972-1002 and pages IO86 IO99 are described.

The alkyl or aryl selenoalkyl sulfonic acids can thus be used represent by reacting the corresponding alkali metal selenate with sulfoalkyl halides.

The symmetrical sulfoalkyl or suIfoaryl diselenides are formed e.g. by hydrolysis of the corresponding selenocyanates of the alkali-alkyl-selenosulfates.

Alkyl selenocyanates or alkyl selenosulfates are formed through Conversion of alkyl halides with alkali metal selenocyanates or selenosulfates.

Aromatic selenocyanates are formed by reacting corresponding diazonium salts with alkali metal selenocyanates.

The marked compounds are found as such or better in the form of their salts, e.g. the alkali, ammonium or Amine salts, use. Examples include the sodium, potassium, ammonium and triethylammonium salts. In the The following table lists compounds to be used according to the invention.

209824/1019

SCHERING AG

Patent department

October 27, 1970

Tabel

2 ^Se 2 2 ^Se 2

CH.

7) INaO S-CH-

9) (NaO ₃ S -, ^

₂ Se ₂

₂ Se ₂ di- (6-potassium sulfohexy1) -diselenide di- (4-potassium sulfobuty1) -diselenide

Di- (5-kallumsulfopropyl) diselenide Di ~ (3-sulfopropyl) -diselenide Di- (5-ammonium-sulfopropyl) -diselenide

Di- (5-triethylammonium sulfopropyl) diselenide

Di- (5-methy1-3-sodium sulfo-propy1) -diselenide

Di- (2-sodium sulfoethy1) diselenide Di- (4-sodium sulfophenyl) diselenide

10) (NaO ^ S

13) CH

Di- (4-sodium sulfophenyl) diselenide

Di - (jj-natriumsulfophenyl) -dise lenid

Di- (4-methoxy-5-sodium sulfo-phenyl) diselenid

Di- (5-methylmereapto-3-sodium sulfophenyl) diselenide

209824/1019

SCHERING AG

Patent department

October 27, 1970

14)

Di- (4-sodium sulf0-3-chloro-pheny1) diselenid

Di- (7-sodium sulfonaphthyl ~ 2) diselenide

Di- (6,8-disodium sulfonaphthyl-2) diselenid

17)

Se- (CHg) ₃ SO Na 3- (phenylseleno) -propylsulfonic acid sodium

18)

5- (p-Nitrophenylseleno) propylsulfonic acid potassium

19) CH,

Se (CHg) ₃ SO ₃ K J- (p-methylphenylseleno) -propylsulfone-

'^ acid potassium

20)

^ ■ χΚ j5- (p-methoxyphenylseleno) -propylsul- · * potassium acid

21) HOOC- ( _v * ~] ySe (CH ₂ J ₃ SO ₃ Na 3- (p-Carboxyphenylseleno) -propylsul-

^ sodium fonsate

22)

CHp-Se (CHp) -, SO, Na I- (benzy lse leno) -propy lsulfonic acid ^ PP sodium

OCH ₂ -CH ₂ Se (CH ₂ ) SO Na> (Phenoxyäthylseleno) -propy1-

^ Sodium sulfonic acid

24)

S0, Na ~ 5- (4-aminopheny lseleno) -propy lsulf on-

J ^ Sodium acid

209824/10 -

SCHERING AG

October 27, 1970

25) CH ^ OOC

S Ο, Κ 3- (p-Carbmethoxyphenylseleno) -propylsulfonsaures potassium

26) (CH) NZ ^) - Se (CH) SO K> (p-Dimethylatninophenylseleno) - -> \ JJ ■> ^ propyl-sulfonic acid potassium

Na 2- (phenylseleno) ~ ethylsulfonic acid sodium

Se (CH ₀ ), SO Na 4- (phenylseleno) -butylsulfonic acid sodium

3- (Sulfolanylseleno) -propylsulfonic acid potassium

0 ü CH ₀ -Se (CH ₀ KSO Na 5- (Furylseleno) -propylsulfonsaures

X / ^dd ->-> sodium

CH

Se (CH ₂ ) ^ SO K 3- (m-methylmercaptophenylseleno) -

^ SO potassium propylsulfonate

SO Na ^ - (CyclohexylmethylselenoJ-propylsul- I sodium fonsate

K 3> (> Pyridylmethylseleno) propylsulfonic acid potassium

/ FaO ₃ S (CH ₂ ) J ^ Se bis (4-sodium sulfobutyl) selenide

S (CH ₂ ) _ / S bis (3-sodium sulfopropyl) selenide

36) / IiO S (CH ₂ ) ^ e

Bis- (2-potassium sulfoethyl) selenide

209824/1019

SCHERiNGAG

Patent department

October 27, 1970

C ₀ H Se (CH ₀ ) .. SO Na

C ₇ H ₇ Se (CH ₀ ), SO-Na

C ₀ H _n "Se (CH ₀ )., SO K

HOOC (CHp) ₂ Se (CHp) ₃ SO K

OH HOCHp-CH-CHp-Se (CHp)

2- (Ethylseleno) -propylsulphonic acid sodium

3- (Propylseleno) -propylsulfonic acid sodium

3- (octylseleno) -propylsulfonsaui'es potassium

^ - (a-CarboxyäthylselenoJ-propylsulfonsaures potassium

5- (2,> dihydroxypropylseleno> propyl potassium sulfonic acid

Additives to be used according to the invention are also suitable also those compounds which, in addition to an organic radical on selenium containing sulfo groups, contain the cyanide or sulfonic acid group contain. These selenocyanates or selenosulfates split in the strongly acidic copper electrolyte to diselenides, Polygamy then represent the actually effective connections.

Some such selenocyanates and selenosulfates are listed in the following table.

Table II

KO S (CH ₂ ) ^ SeCH KO ₅ S (CH ₂ ) ^ SeCH KO ₇ S (CH ₂ ), SeCN KO S (CHg) ₂ SeCN

^K0 ^ ^s (Q ^H o) /; SeSO K A

cd -potassium sulfohexyl selenocyanate 60-potassium sulfobutyl selenocyanate CO -potassium sulfopropyl selenocyanate OJ-potassium sulfoethyl selenocyanate

Cu -potassium sulfohexylselenosulfonic acid « _Ä potassium
9824/1019 -9-

SCHERING AG

Patent department

October 27, 197O

6) KO S (CH ₂ ) ^ SeSO K

7) KO ₃ S (CH ₂ J ₃ SeSO ₅ K

8) KO S (CHg) ₂ SeSO K

<* 3-Kaliumsulf vbutylselenosulfonsaures potassium

Cu-potassium sulfopropylselenosulfonic acid potassium

^. Potassium sulfoäthylselenosulfonsaures potassium

9) NaO.

CH ₂ SeCN

p- (sodium sulfo) benzyl selenocyanate

10) NaO-S - / "\ - SeCN

p- (sodium sulfο) -phenylselenoeyanate

p- (sodium sulfo) -benzylselenosulfonic acid sodium

12) NaO, S.

NaO

SeCN 7- (sodium sulfo) -2-naphthyl selenoeyanate

eCN

4-methoxy-; 5-sodium sulfo-phenylselenocyanate

6,8-di (sodium sulfo) -2-naphthyl selenocyanate

As an electrolyte for the deposition of copper coatings with additives of the substances according to the invention is generally a sulfuric acid copper sulfate solution of the following composition is used:

Copper sulfate CuSO ^. 5 HgO. .. 125- to. 260 g / liter sulfuric acid H ₂ SO ₂ , 20 to 85 g / liter.

- 10 -

209824/1019

7053860 SC ^HER 1NG AG

Z U ü O O U U Patent Department

October 27, 1970

Instead of copper sulfate, other copper salts can also be used, at least in part. The sulfuric acid can partially or be replaced entirely by fluoroboric acid, phosphoric acid and / or other acids. The electrolyte can be chloride-free or - which is usually advantageous for improving the gloss and leveling - chlorides, e.g. alkali chlorides, or hydrochloric acid in amounts from 0.001 to 0.2 g / liter contain.

The amounts in which the substances according to the invention the Copper baths have to be added in order to achieve an improvement in the copper deposition, surprisingly very low and are about 0.0005 to 0.5 g / liter, preferably 0.0005 to 0.1 g / liter. One obtains with these additives a clear grain refinement, in certain current density ranges even shiny copper coatings.

However, the substances according to the invention are also particularly suitable to deposit haze-free, high-gloss coatings in conjunction with other common brighteners and / or wetting agents, which show a strong leveling of the roughness of the base material, but are nevertheless very ductile and high Have extensibility.

Known additives which can be used together with the substances according to the invention are primarily suitable

- 11 209824/1019

Patent department

October 27, 1970

Line of high molecular weight compounds containing oxygen. The quantities of these substances which are added to the copper electrolyte are approximately from O ₁ O to 20.0 g / liter, preferably from 0.02 to 8.0 g / liter. Table III contains examples of high molecular weight compounds containing oxygen:

Table III

1) polyvinyl alcohol

2) carboxymethyl cellulose
5) polyethylene glycol

4) polypropylene glycol

5) Polyglycol stearate

6) oleic acid polyglycol ester

7) stearyl alcohol polyglycol ether

8) nonylphenol polyglycol ether

9) Reaction products of alkylene oxides with amines.

As further, per se known compounds, the copper electrolyte can be added, for example:

Polymeric phenazonium compounds, polyalkyleneimines, polyvinylamines, polyvinylimidazole, polyvinylpyrrolidone, Phenazine dyes and the organic thio compounds already mentioned.

209824/1019 ~ ¹² "

SCHERING AG

- 12 7 2 ?. October 1970

The following examples explain the use of the substances according to the invention.

example 1

Copper sulfate (CuSO ^. 5 H ₃ O) 220 g / liter

Sulfuric acid, conc. 50 g / liter

Di- (j5-potassium sulfopropyl) diselenide 0.05 g / liter temperature: 25 ° C
Current density: 4.0 A / dm ²
Movement of goods

B is ρ ie 1

Copper fluoroborate (Cu (BF ^) ₂ ) 500 g / liter

Fluoroboric acid 20 g / liter

2- (Phenylseleno) -äthylsulfonsaures 0.3 g / liter

sodium

Temperature: 25 ° C
Current density: 8.0 A / dm ²

Electrolyte movement through
Air injection

Example 3

Copper sulfate (CuSO ^. 5 HgO) 200 g / liter

Sulfuric acid, conc. 60 g / liter

Chloride ions 0.0} g / liter

Di - (^ - SuIfopropyl) -diselenide 0.08 g / liter Temperature: 22 ° C
Current density: 4.0 A / dm ²

Movement of goods

209824/1019 - ¹ ^ "

SCHERING AG

Patent department

October 27, 1970

example

Copper sulfate (CU30.. 5 HO) sulfuric acid * conc. Chloride ions di- (j5-potassium sulfopropyl) diselenide polypropylene glycol

ο Temperature: 26 C

Current density: 5.0 A / dm ² air blowing

g / liter

60 g / liter

0.05 g / liter

0.01 g / liter

0.5 g / liter

Example yy

Copper sulfate (CuSO ^. 5 HgO)

Sulfuric acid, conc.

Chloride ions di- (4-sodium sulfophenyl) diselenide Nonylphenol polyglycol ethers

Temperature: 22 ° C

Current density: 4.0 A / dm ² movement of goods

g / liter g / liter

0.05 g / liter

0.03 g / liter

4.0 g / liter

- 14 -

209824/1019

Patent department

October 27, 1970

Example 6

Copper sulfate (CUSO ^. 5 H ₃ O) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.02 g / liter

Di- (4-methoxy-3-sodium sulfo-phenyl) -

diselenide 0.02 g / liter

Polyethylene glycol. 0.2 g / liter

Temperature: 22 ° C
Current density: 5.0 A / dm
Air injection

example

Copper sulphate (CuSO ^. 5 H ₃ O) 150 g / liter

W sulfuric acid, conc. 3O g / liter

Chloride ion 0.03 g / liter

3- (Phenylseleno) propylsulfonic acid

Sodium 0.1 g / liter

Carboxymethyl cellulose 0.1 g / liter

Temperature: 22 ° C
Current density: 3.0 A / dm ²
Movement of goods

- 15 -

2 (19824/1019

Patent department

October 27, 1997

Example 8

Copper sulfate (Cu3O ^. 5 H ₃ O) 220 g / liter sulfuric acid, conc. 50 g / liter

Chloride ion 0.08 g / liter

3- (Benzylseleno) propylsulfonic acid

Sodium 0.01 g / liter

ω-potassium sulfoxy iselenocyanate 0.02 g / liter Polyethylene glycol 0.1 g / liter

Temperature: 25 ° C
Current density: 5.0 A / dm ²
Air injection

example

Copper sulfate (CuSO ^. 5 HgO) 220 g / liter

Sulfuric acid, conc. 5 ° g / liter

Fluoroboric acid 10 g / liter

Chloride ion 0.05 g / liter

^ - (p-Carbmethoxyphenylselenoi-propyl-

potassium sulfonate 0.04 g / liter

Oleic acid polyglycol ester 1.0 g / liter

Temperature: 25 ° C
Current density: 4.0 A / dm ²
Movement of goods

- 16 209824/1019

Patent department

- October 16-27, 1970

Example 10

'Copper sulfate (CuSO ^. 5 H ₃ O) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.05 g / liter

3- (SuIfolanylseleno) propylsulfonic acid

Potassium 0.06 g / liter

Stearyl alcohol polyglycol ether 1.5 g / liter Temperature: 25 ° C
Current density: 4.0 A / dm ²
Movement of goods

Example 11

Copper sulfate (CuSO ^. 5 H ₉ O) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.05 g / liter

3- (m-methylmercaptophenylseleno) -

Potassium propylsulfonate 0.02 g / liter

Stearyl alcohol polyglycol ether 1.5 g / liter Temperature: 25 ° C
Current density: 4.0 A / dm ²
Movement of goods

- 17 -.

209824/1019

SCHERING AG

Patent department

October 27, 1970

example

12th

Copper sulfate (CuSO _4. 5 H ₃ O)

Sulfuric acid, conc.

Chloride ions

Bis (4-sodium sulfobutyl) selenide

W-potassium sulfohexylselenosulfonic acid potassium

Polypropylene glycol temperature: 25 ° C current density: 5.0 A / dm ² air blowing

g / liter

60 g / liter

0.05 g / liter

0.01 g / liter

0.01 g / liter

0.3 g / liter

example

13th

Copper sulfate (CuSO.. 5 HgO) Sulfuric acid, conc. Chloride ions

3- (Ethylseleno) -propylsulphonic acid sodium

Nonylphenol polyglycol ether Temperature: 25 ° C Current density: 5.0 A / dm ² movement of goods

g / liter g / liter

0.03 g / liter

0.08 g / liter

1.0 g / liter

- 18 -

onzwzn SCHERING AG

2 ?. October 1970

Example 1Λ

Copper sulfate (CuSO ₂ ^. 5 HgO) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.03 g / liter

5 ™ (Octylseleno) propylsulfonic acid

Potassium 0.1 g / liter

Polypropylene glycol 0.5 g / liter

Temperature: j50 ° C
Current density: 5.0 A / dm ²
Movement of goods

Example 15

Copper sulfate (CuSO ^. 5 HgO) 220 g / liter Sulfuric acid, conc. 60 g / liter

Chloride ions 0.05 g / liter

AD potassium sulfoethyl selenocyanate 0.05 g / liter stearic acid polyglyeol ester 2.0 g / liter temperature ι ? 5 ° C
Current density: K _t 0 A / dm ²
Movement of goods

- 19 *

Patent department

October 27, 1970

- 19 - '

Example 16

Copper sulfate (CuSO ^. 5 H ₃ O) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.05 g / liter

to-Kaliumsulfoäthylselenosulfonsaures

Potassium 0.02 g / liter

Polyethylene glycol 2.0 g / liter

Temperature: 25 ° C
Current density: 5.0 A / dm
Air injection

B ei s ρ i e 1

Copper sulfate (CUSO ^. 5 H ₃ O) 220 g / liter sulfuric acid, conc. 60 g / liter

Chloride ion 0.04 g / liter

G -> - Kaliumsulfoäthy lselenosulfonsaures

Potassium 0.05 g / liter

Nonylphenol polyglycol ether 1.0 g / liter temperature: 25 ° C
Current density: 4.0 A / dm ²
Movement of goods

- 20 -

209824/10 19

SCHERiNGAG

Patent department

- 20 -

October 27, 1970

Example l8

Copper sulfate (CuSO ^. 5 HO) 200 g / liter Sulfuric acid, conc. 50 g / liter

Chloride ion 0.06 g / liter

p- (sodium sulfo) benzyl selenocyanate 0.06 g / liter nonylphenol polyglycol ether 2,, 0 g / liter temperature: 20 ° C
Current density: 3.0 A / dm ²
Movement of goods

B e 1 s ρ i e 1 19

Copper sulfate (CUSO ^. 5 H ₃ O) 200 04 g / liter Sulfuric acid, conc. 60 02 g / liter Chloridioneh 0, 5 g / liter 7- (sodium sulf0) -2-naphthylseleno-
cyanate 0, g / liter Stearyl alcohol polyglycol ether 1, g / liter Temperature: 25 ° C Current density: 4.0 A / dm ² Movement of goods

- 21 -

209824/1019

SCHERING AG

Patent department

October 27, 1970

example

20th

Copper sulfate (CuSO ^. 5 H ₂ O) sulfuric acid, conc. Chloride ions

^ -Methoxy-jJ-sodium sulfo-phenyl be cyanate

25 ° C

Polyethylene glycol temperature:
Current density: 5.0 A / dm air injection

g / liter g / liter

0.04 g / liter

0.06 g / liter

0.6 g / liter

- 22 -

209854/1018

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Claims (6)

Pate ntansprüche Acid aqueous electrolyte for the deposition of copper coatings, characterized by a content of at least one compound of the general formula H ₁ - in which R, and Rg are identical or different and represent an optionally mono- or polysubstituted aromatic, aliphatic, cycloaiiphatic, araliphatic or heterocyclic hydrocarbon radical, at least one of the two radicals containing a sulfonic acid group, or in which R _{1 contains} the aforementioned? Has meaning and R ₂ the Cyanld «· or the Suifojisäuresruf ^ e« and η the number 1 or 2 Agt _# pö # r their 2. Electrolyte according to claim I ₁ , containing Veri> iiidwng € | p of the general form) -,% n #ejr Jl- Phej ^ L, Ä ^ ropheny ^, AIikylphenyl ^ AIko ^ phenyl ,, Cart> O3 ^ j> litayl * Carbaetho ^ srphenyl PleaejthylaBfiinophenyl, AIkylfje ^ oaptophen-yl, Aminp-pheny 1, Alkyl mit vor? IMgsj (iel © e 2 fei «8 Kphlen ^ offatomen, Phenoxyalkyl, SuIfXianyl, PMryl, Cyciohe ^ lalkyl, ,, sulfoalkyl i »i ^. jrpr- Patent department "October 27, 1970 - 23 - preferably 2 to 6 carbon atoms, sulfophenyl, alkoxysulfophenyl, alkylmercapto-sulfophenyl, halosulfophenyl, sulfonaphthyl, disulfonaphthyl or sulfophenyl-alkyl and R ₂ sulfoalkyl with preferably 2 to 6 carbon atoms, sulfophenyl, alkoxysulfophenyl, alkylmercapto-sulfophenyl, Sulfonaphthyl, disulfonaphthyl or sulfophenylalkyl and η represent the numbers 1 or 2. 3. Electrolyte according to claim 1, containing compounds of the general Formula in which R-, sulfoalkyl with preferably 2 to 6 carbon atoms, sulfophenyl, alkoxysulfophenyl, alkylmercapto-sulfophenyl, Halosulfophenyl, sulfonaphthyl, disulfonaphthyl, sulfophenylalkyl, Rp the cyanide or sulfonic acid group and η is the number 1. 4. Electrolyte according to Claims 1 to J, characterized in that that he contains the selenium compounds in amounts of 0.0005 to 0.5 g / liter, preferably from 0.0005 to 0.1 g / liter. 5. Electrolyte according to Claims 1 to 3, characterized in that that it also contains high molecular weight compounds containing oxygen. 6. electrolyte according to claim 5 »characterized in that it the oxygen-containing high molecular compounds in quantities from 0.01 to 20.0 g / liter, preferably from 0.02 to 8.0 g / liter, contains. 209824/1019 Board of Directors: Hsns-JDr ₀ on Hemnnn · K «rl Otto MUtetstenschald Chairman of the Supervisory Board: Dr. Jur. Eduard v. Schwarlikoppen 1 Berlin 65, MUllarstraS 170-172 Or. Rur. nat. Gorhaid Rnapä · Or.-Ing. Horst WIUoI SIUder Gesellschaft: Dtrlln and B «rgk> m * n Postfach 69 Commercial rogue applications: AG Charlottenburg 93 HRB 2S3 and AG Kamort 6 HRB 7t. Postschodc: Berlin Wstt 11