DE1621351C3 - Stabilized reductive copper bath - Google Patents

Description

The invention relates to a bath stabilized by selenium compounds for the reductive deposition of Copper.

Technical processes are used to apply metal layers to a wide variety of base materials increasing attention, in which the metals are reductively deposited from baths without an external power source will. In particular, the deposition of copper by reduction has increased in recent years Increasing importance found, since reductive copper precipitates to produce conductive layers Plastic panels, e.g. B. in the electronics industry for the production of printed circuits, especially are suitable.

The bath compositions of reductive copper baths known so far have, however, the Disadvantage of a very low stability, so that it is necessary to achieve the highest possible deposition rate usually have to be heavily overloaded and discarded after the metal has been worked out will.

In order to increase the bath stability, there are already additives, preferably sulfur-containing compounds, became known, but these may only be added in small amounts, since larger ones Concentrations greatly reduce the rate of deposition of the metal or the deposition can even prevent it. In some compounds it has also proven to be disadvantageous that these cause the copper layer to darken. Because of especially at higher temperatures In addition, the sulfur-containing compounds often have a low resistance to alkali and therefore do not succeed in reductive To stabilize copper baths satisfactorily for a longer period of time.

It has also been proposed to use monoselenides of the general formula

in which R ₁ and R _{2 are} identical or different and denote hydrogen, an organic radical or a monovalent metal atom, and or their selenium • niobium compounds to be used as stabilizing bath additives. However, these compounds mainly only have a stabilizing effect and have little influence on the quality of the precipitates deposited. It has now been found that diselenides of the general formula

Rj Se Se R ₂

in which R ₁ and R _{2 are} identical or different and mean a monovalent metal equivalent or an organic radical, reductive copper baths both to stabilize permanently and to improve the quality of the precipitates deposited therefrom.

As monovalent metal equivalents, for. B.

consider Na, K, Ca / 2 or Al / 3 and others; as organic residues are z. B. called aliphatic, cycloaliphatic, aromatic and araliphatic radicals, which are optionally also substituted and / or by one or more heteroatoms, such as oxygen, nitrogen or sulfur, and / or one or more Heteroatom groups such as

S = O

or

can be interrupted, as well as the Aracylrest.

Substituents for the organic radicals mentioned are, for. B. halogen atoms such as chlorine, bromine and others, Hydroxyl groups, alkyl groups such as methyl and ethyl and others, aryloxy groups such as phenoxy and others, alkoxy groups such as Methoxy and ethoxy and others, acyloxy radicals such as acetoxy and others, the nitro and cyano groups, the carboxyl and the sulfonic acid group in free or functional

'modified form, e.g. B. as esters or salts, heterocyclic radicals such as tetrahydrofuryl and others, as well as the radicals

or

H ₂ N-CO —NH-CO-

Ar —NH-CO-

Reductive copper baths which contain the compounds to be used according to the invention are suitable for the deposition of copper layers on metals or appropriately pretreated and activated

te plastics with absolute stability of the copper reduction bath. Due to their particular stability, these baths work without special maintenance and do not need after the respective use. to be renewed. It's just through To supplement the entrainment of bath losses. The copper layers deposited from these baths are particularly decorative and are characterized by a bright, salmon-like metallic sheen.

Compounds to be used according to the invention are e.g. B. the following:

K ₂ Se ₂

(CH ₃ - CH ₂ - CH ₂ - CH ₂ -) ₂ Se ₂ (CH ₃ (CH ₂ ) ₄ ~~) ₂ Se ₂ (CH ₃ - (CH ₂ ) ₅ -) ₂ Se ₂ (CH ₃ - ( CH ₂ ) ₆ -) ₂ Se ₂

\ HOCH ₂ - CH - CH ₂ -J ₂ Se ₂ (KO ₃ S- (CH ₂ ) ₃ -) ₂ Se ₂ (KO ₃ S- (CH ₂ ) ₂ -) ₂ Se ₂ (NaO ₃ S- (CH ₂ ) ₄ -) ₂ Se ₂ , (NaOOC - CH ₂ -) ₂ Se ₂ (KOOC - CH ₂ - CH ₂ -) ₂ Se ₂ (KOOC - (CH ₂ ) ₃ -) ₂ Se ₂ (KOOC ~ (CH ₂ ) ₁₀ -) ₂ Se ₂ C ₆ H ₅ - Se - Se - C ₆ H ₅ (P-CH ₃ C ₆ H ₄ -) ₂ Se ₂ (P-CH ₃ OC ₆ H ₄ -) ₂ Se ₂ ( P-NO ₂ - C ₆ H ₄ -) ₂ Se ₂ (0-CH ₃ CO - C ₆ H ₄ -) ₂ Se ₂ (2-C ₆ H ₅ - C ₆ H ₄ -) ₂ Se ₂ (P- KO ₃ S- C ₆ H ₄ -) ₂ Se ₂ ■ (p-Cl - C ₆ H ₄ -) ₂ Se ₂ (p-HOOC - C ₆ H ₄ -) ₂ Se ₂

H ₂ N-

• C - NH - C - CH ₂ -

(C ₆ H ₅ CH ₂

Se,

- CH ₂ - C - NH

Il ο

NO-

■ CH ₂ - Se ₂ potassium diselenide

Di-n-butyl diselenide Di-n-amyl diselenide Di-n-hexyl-diselenide Di-n-heptyl-diselenide

Di- (1,3-dihydroxypropyl) -diselenide Di- (potassium sulfopropyl) -diselenide Di- (potassium sulfoethyl) diselenide di-sodium sulfobutyl) diselenide bis (sodium carboxymethyl) diselenide Bis- (potassium carboxyethyl) -diselenide bis- (kaliuracarboxypropyl) -diselenide bis- (potassium carboxydecyl) -diselenide Diphenyl diselenide Di-p-tolyl diselenide Di- (p-methoxyphenyl) -diselenide di- (p-nitrophenyl) -diselenide bis- (o-acetylphenyl) -diselenide Di-2,2'-biphenylyl-diselenide bis- (p-potassium sulfophenyl) -diselenide bis- (p-chlorophenyl) -diselenide Bis (p-carboxyphenyl) diselenide

Diselenium diacetylurea dibenzyl diselenide

Diselendiglycolic acid diphenylamide

Bis (p-nitrobenzyl) diselenide

CH,

Bis (p-methylbenzyl) diselenide

NC-

Bis (p-cyano-benzyl) -diselenide

HOOC

CH ₂ -Se ₂ bis (p-carboxybenzyl) diselenide

Br

Bis (p-bromobenzyl) diselenide

C ₂ H ₄ -Se ₂

(HOCH ₂ - CH ₂ - CH ₂ -) ₂ Se ₂

CH, -

Se,

0-CH ₂ -CH ₂ -Se ₂

Bis (ß-phenylethyl) diselenide

Bis (3-hydroxypropyl) diselenide

Bis (u-tetrahydrofurylmethyl) diselenide

Bis (/ i-phenoxyethyl) -dise] enide

Bis (cyclohexyl) diselenide
Bis (cyclopentyl) diselenide

Of the compounds, those with a water-solubilizing group are particularly suitable, because these are easy to dose and are able to stabilize for a long time. Containing reductive copper baths one or more of these compounds are extremely durable.

The compounds mentioned are known per se or can be prepared in analogy to known processes produce how they z. B. in H ο u b e η - W e y 1 »methods derorganic chemistry ", Vol. 9, pp. 1086 to 1105, are described.

The use of additives to stabilize reductive copper baths of the usual composition can take place in the concentrations of about 0.0001 g / 1 to 0.300 g / l bath liquid, whereby the compounds can be added either alone or mixed with one another. According to the invention stabilized copper baths also contain the usual components, i. H. Copper salts, Reducing agents, buffer substances, complexing agents as well as wetting and brightening agents, among others.

The following examples describe some copper baths according to the invention, with which, for example Objects made of metals, plastics or other materials are copper-plated in a known manner can be.

Example 3

CuSO ₄ -5H ₂ O 8g / l

Disodium ethylenediamine tetra

acetic acid 16 g / l

Sodium hydroxide 8 g / l

Paraformaldehyde 15 g / l

Dibutyl diselenide 0.020 g / l

Example 4

CuSO ₄ · 5H ₂ O 20g / l

Disodium ethylenediamine tetra

acetic acid 35 g / l

Sodium hydroxide 23 g / l

Paraformaldehyde 15 g / l

Dibenzyl diselenide 0.010 g / l

Example 5

CuSO ₄ -5H ₂ O 12g / l

Triethylenediamine 12 g / l

Sodium hydroxide 16 g / l

Paraformaldehyde 10 g / l

Potassium diselenide 0.001 g / l

example 1

CuSO ₄ -5H ₂ O 10g / l

Disodium ethylenediamine tetra

acetic acid 20 g / l

Sodium hydroxide 16 g / l

Paraformaldehyde 4 g / l

Di- (potassium sulfopropyl) diselenide 0.002 g / l

Example 2

CuSO ₄ -5H ₂ O 20g / l

Disodium ethylenediamine tetra

acetic acid 25 g / l

Sodium hydroxide 8 g / l

Paraformaldehyde 13 g / l

Di- (2,3-dihydroxypropyl) -diselenide .. 0.050 g / l

Example 6

CuSO ₄ -5H ₂ O 10g / l

Triethylenetetramine 8 g / l

Sodium hydroxide 16 g / l

Paraformaldehyde; 16 g / l

Bis (4-carboxyphenyl) diselenide 0.100 g / l

Example7

CuSO ₄ -5H ₂ O 10g / 1

Disodium ethylenediamine tetra

acetic acid 20 g / l

Sodium hydroxide 12 g / l

Paraformaldehyde 15 .g / l

Bis- (w-potassium carboxyldecyl) -

diselenide 0.150 g / l

16

Example 8

CuSO ₄ -5H ₂ O 10g / l

Rochelle salt (potassium sodium

tartrate) 24 g / l

Sodium hydroxide 24 g / l

Paraformaldehyde 12 g / l

Bis (w-potassium sulfopropyl) diselenide 0.105 g / l

Example 9

CuSO ₄ -5H ₂ O 10g / l

Trisodium salt of hydroxyethyl

diaminäthylenetriacetic acid 19 g / l

Sodium hydroxide 11 g / l

Paraformaldehyde 8 g / l

Bis (w-potassium sulfopropyl) diselenide 0.010 g / l

Example 10

CuSO ₄ -5H ₂ O 10g / l

Disodium ethylenediamine tetra

acetic acid 20 g / l

Sodium hydroxide 16 g / l

Paraformaldehyde 9 g / l

Di (4-sulfophenyl) diselenide 0.030 g / l

Example 11

CuSO ₄ -5H ₂ O 10g / l

Disodium ethylenediamine tetra-

acetic acid 20 g / l

Sodium hydroxide 16 g / l

Paraformaldehyde 8 g / l

Bis (4-methoxyphenyl) diselenide .... 0.010 g / l

Example 12

CuSO ₄ -5H ₂ O 15g / l

Disodium ethylenediamine tetra-

acetic acid 25 g / l

Sodium hydroxide 19 g / l

Paraformaldehyde 15 g / l

Bis (p-nitrobenzyl) diselenide 0.001 g / l

45

Example 13

CuSO ₄ -5H ₂ O 20g / l

Disodium ethylenediamine tetra

acetic acid 25 g / l

Sodium hydroxide 10 g / l

Paraformaldehyde 13 g / l

Bis (p-cyano-benzyl) -diselenide 0.0009 g / l

Example 14

CuSO ₄ -5H ₂ O 20g / l

Disodium ethylenediaminetetraacetic acid 25 g / l

351

Sodium hydroxide 9 g / l

Paraformaldehyde 15 g / l

Bis (p-carboxybenzyl) diselenide 0.005 g / 1

Example 15

CuSO ₄ -5H ₂ O 20g / l

Disodium ethylenediamine tetra

acetic acid 30 g / l

Sodium hydroxide 23 g / l

Paraformaldehyde 15 g / l

Bis (p-bromobenzyl) diselenide 0.010 g / l

Example 16

CuSO ₄ -5H ₂ O 19 g / 1

Disodium ethylenediamine tetra

acetic acid · 25 g / l

Sodium hydroxide 20 g / l

Paraformaldehyde 19 g / l

Bis (3-hydroxypropyl) diselenide 0.030 g / l

Example 17

CuSO ₄ -5H ₂ O 25 g / l

Disodium ethylenediamine tetra

acetic acid 30 g / l

Sodium hydroxide 20 g / l

Paraformaldehyde 10 g / l

Bis (/ i-phenoxyethyl) diselenide 0.020 g / l

Example 18

CuSO ₄ · 5H ₂ O 10 g / l

Disodium ethylenediamine tetra

acetic acid 20 g / l

Sodium hydroxide 12 g / l

Paraformaldehyde 15 g / l

Bis- (a-tetrahydrofurylmethyl) -

diselenide 0.010 g / l

Example 19

CuSO ₄ -5H ₂ O 15 g / l

Disodium ethylenediamine tetra

acetic acid 25 g / l

Sodium hydroxide 15 g / l

Paraformaldehyde 10 g / l

Bis-icyclohexyrJ-diselenide 0.008 g / l

Example 20

CuSO ₄ -5H ₂ O 20 g / l

Disodium ethylenediamine tetra

acetic acid 25 g / l

Sodium hydroxide 18 g / l

Paraformaldehyde 15 g / l

Bis (cyclopentyl) diselenide 0.003 g / l

509 687/53

Claims (3)

Patent claims: 1. Stabilized reductive copper bath, labeled by a content of at least one compound of the general formula R ₁ -Se-Se-R ₂ in which R ₁ and R _{2 are} identical to or different from one another and represent a monovalent metal equivalent or an organic radical. 2. Stabilized reductive copper bath containing at least one compound of the general formula according to claim 1, wherein R ₁ and R _{2 are} identical or different from one another and are a monovalent metal equivalent or an aliphatic, cycloaliphatic ^ aromatic or araliphatic radical, which is optionally also substituted and / or can be interrupted by heteroatoms and / or heteroatom groups, or denote the aracyl radical. 3. Stabilized reductive copper bath according to claim 1 or 2, containing the marked Compounds in a concentration of about 0.0001 to 0.300 g / l bath liquid.