CS271147B1 - Lustre forming admixture - Google Patents

Abstract

The solution concerns the brightener into acid galvanic copper baths. It consists of dithioderivates of carbamoyl-4-butane sulfone acid of the general formula R-(CH2)4S03<->Me<+>, where Me is natrium, potassium or hydrogen, and R is residuum of the general formula IIa or IIb, where R<1> is o-disubstituted aromatic nucleus with the number of carbon atoms 6 to 20 or heteroaromatic nucleus with the number of carbon atoms 3 to 10, sulphur, nitrogen or oxygen containing possibly halo-, nitro-, sulfo-, hydroxy-, amino- and/or mercapto groups or alkylene with the carbon number of 2 to 20. R<2> and R<3> are the same or different alkyl residua or hydrogen. The brightener further contains tenside with the molecular weight of 200 to 15,000 in the weight ratio 100 : 1 to 1 : 50,000.<IMAGE>

Description

The present invention relates to a glazing additive for acidic galvanic copper baths. The additive consists of carbamoyl-4-butanesulfonic acid dithioderivatives of the general formula R- (CH ₂ ) ₄ SO ² Me ⁺ , where Me is sodium, potassium or νοοίκ and R is a radical of the formula IIa or IIb, wherein R ¹ is an o-disubstituted aromatic ring with a carbon number of 6 to 20 or a heteroaromatic nucleus having a carbon number of 3 to 10, sulfur, nitrogen or oxygen containing optionally halo-, nitro-, sulfo-, hydroxy-, amino- and / or mercaptoskuoins, or alkylene having a carbon number of 2 to 20 . ^from R and FR are identical or different alkyl radicals or hydrogen. The additive further comprises a surfactant having a molecular weight of 200 to 15,000 in a weight ratio of 100 to 1 to 50,000.

Italy (11) (13) B1 (51) Int. Cl. ⁵ C 25 0 3/38 C 07 D 277/74 C 07 OJ C 333/20

Ila lib

CS 271 147 Bl

BACKGROUND OF THE INVENTION The present invention relates to a brightener additive for a sulphate, strongly acidic galvanic copper bath having a high depth efficiency, which is suitable, for example, for metallization of holes in the production of printed circuit boards.

Due to the high sulfuric acid content (up to 200 g / l) and the low copper content (17 to 30 g / l), the plating baths currently in use are unable to work without a brightener. A wide variety of brighteners are known, some of which cannot be used in the environment, others have a narrow range of usable current densities to eliminate the shiny coating and the appropriate ductility of the excluded copper. These drawbacks are overcome by the use of dimethyldithiocarbamoyl-1-propanesulfonic acid sodium salt and related derivatives (U.S. Pat. No. 3,725,220). The disadvantage of this substance is the necessity to use highly carcinogenic 1,3-propanesultone in its synthesis.

This disadvantage is overcome by the brightening agent of the acidic copper baths according to the invention. It consists essentially of carbamoyl-4-butanesulfonic acid dithioderivatives of the general formula I

R- (CH ₂ ) ₄ SO ₄ Me ⁺ (I), wherein Me is sodium, potassium or hydrogen and R is a radical of formula (SR);

R <, C-S- (IIIa) ^ N-C-S- (IIb),

Wherein R is an o-disubstituted aromatic or heteroaromatic nucleus containing optionally halo-, nitro-, sulfo-, hydroxy-, amino- and / or mercapto groups or alkylene of 2 to 20 carbon atoms, R, R being the same or different alkyl radicals having 1 to 6 carbon atoms or hydrogen, and from an ethoxylated amine, alcohol, thiol or phosphate surfactant having a molecular weight of 200 to 15,000 in a weight ratio of 100; The presence of said type of surfactant improves the effectiveness of the additive, in particular by increasing the gloss of the deposited copper layer. The surfactant itself does not act as a brightener.

The concentration of the salt of said butanesulfonic acid in the working solution is effective in the range of 0.1 to 100 mg / l, for the surfactant based on the polyethoxylated compound in the range of 1 to 5,000 mg / l.

An aqueous solution of copper sulphate and sulfuric acid with the addition of chloride ions up to 80 mh / l is used as the basic galvanic bath.

Gloss-forming additive is used both for the deployment of the galvanic copper bath and for its maintenance according to the appearance of the coating or the time passed. The additive is not sensitive to overdose. The deposited copper is ductile; when applied to the printed circuit boards, there is no breakage at 260 ° C for 20 seconds. The depth efficiency in the holes is 90 to

100% at 0.8 mm hole diameter and 1.5 mm material thickness. The bath temperature can vary from 0 to 35 ° C, the range of usable current densities is 0.5 to 5 A / dm ² .

Example 1

Gloss-forming additive for acid galvanic baths containing 1 mg / l of sodium N, N-dimethyldithiocarbamoyl-4-butanesulfonic acid and 1 300 polyethylene glycol of 50 mg / l.

For galvanic copper baths are prepared by dissolving 117 g of copper sulphate, 190 g of sulfuric acid, 50 mg of chloride ions with a brightener addition of vials of water. Coppering takes place at room temperature and a voltage of 1.5 to 2 A / dm of the surface area. Due to the 100% current efficiency, the deposited copper layer is proportional to time and current density. The deposited copper forms a uniform layer that is smooth and ductile.

CS 271 147 B1

Example 2

Gloss-forming additive for acid galvanic baths containing hyl-dithiocarbamoyl-4-butanesulfonic acid at a concentration of 1 mg / l with a molecular weight of 6,000 at a concentration of 100 mg / l.

sodium salt of N, N-dimethylene glycol s

Example 3

Gloss - forming additive for acid galvanic baths containing

2-mercaptobenthiazolyl-4-butanesulfonic acid at a concentration of 10 mg / L and polyethoxylated nonylphenol with 10 molecules of oxirane at a concentration of 25 mg / L.

Example 4

Gloss-forming acid addition agent containing 50 mg / l of N, N-dimethyldithiocarbamoyl-4-butanesulfonic acid potassium salt and polyethoxylated ethylene amine with 2 to 10 molecules of oxirane at 25 mg / l.

Example 5

Gloss-forming additive for acid galvanic baths containing 20 mg / l of N, N-dimethyldlthiocarbaaoyl-4-butanesulphonic acid sodium salt and 1 500 mg / l of polyethylene glycol.

Example 6

Gloss-forming additive for acid galvanic baths, containing N, N-dibutyldithiocarbamoyl-4-butanesulfonic acid sodium salt at a concentration of 30 mg / l and polyethoxylated ethylenediamine with a molecular weight of 12,000 at a concentration of 100 mg / l.

SUBJECT OF THE INVENTION

Claims (1)

Glucurizing additive for acidic galvanic copper baths, characterized in that it consists of carbamoyl-4-butanesulphonic acid dithio derivatives of the general formula I R- (CH ₂ ) ₄ SO'Me ⁺ where Me is sodium, potassium or hydrogen and R is the radical of the formula Ha or lib that (I). WITH R CS \ Z (IIa) (IIa), wherein R 1 is an o-disubstituted aromatic nucleus having a carbon number of 3 to 10, a sulfur, nitrogen or optionally halo-, nitro-, carbon-numbering 2 to 20 carbon atoms R ^a, R are identical or different alkyl radicals of carbon number one to six, or hydrogen, and surfactant based on ethoxylated amine, alcohol, thiol or fosfáru having a molecular weight of 200 to 15,000 in a weight ratio of 100: 1 to 1: 50 000. or carbon 6 to 20 oxygen containing sulfo-, hydroxy-, amino- and / or mercapto groups or alkylene