SOLUTION AND PROCESS FOR THE PRE-TREATMENT OF COPPER SURFACES USING AN N-ALKOXYLATED ADHESION-PROMOTING COMPOUND

Abstract

A method for pretreating a copper surface for the subsequent formation of a firmly adhesive bond between the copper surface and a plastic material substrate. The method comprises bringing a copper surface into contact with: a) hydrogen peroxide; b) an acid; c) a nitrogen-containing, five-membered, heterocyclic compound; and d) a lactam, amide, or polyamide, connected at one or more of its nitrogen atoms with at least one residue of formula (I),

##STR00001##

wherein: n is an integer from 1 to 100; R.sub.1 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; R.sub.2 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; and each R.sub.1 and R.sub.2 in a (CHR.sub.1CHR.sub.2O) moiety is selected independently of each R.sub.1 and R.sub.2 in another (CHR.sub.1CHR.sub.2O) moiety.

Claims

1-7. (canceled)

8. A method for pre-treating a copper surface, the method comprising; (A) contacting the copper surface with a first solution comprising: a) hydrogen peroxide; b) an acid; and c) a nitrogen-containing, five-membered, heterocyclic compound; and (B) contacting the copper surface with a second solution comprising a nitrogen-containing, adhesion-promoting compound selected from a lactam, amide or polyamide and that is connected at one or more of its nitrogen atoms with at least one residue of formula (I) ##STR00015## wherein: n is an integer from 1 to 100; R.sub.1 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; R.sub.2 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; and each R.sub.1 and R.sub.2 in a (CHR.sub.1CHR.sub.2O) moiety is selected independently of each R.sub.1 and R.sub.2 in another (CHR.sub.1CHR.sub.2O) moiety.

9. The method of claim 8, wherein the nitrogen-containing, adhesion-promoting compound is a compound of formula (II) ##STR00016## wherein: n is an integer from 1 to 100; R.sub.1 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; R.sub.2 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; each R.sub.1 and R.sub.2 in a (CHR.sub.1CHR.sub.2O) moiety is selected independently of each R.sub.1 and R.sub.2 in another (CHR.sub.1CHR.sub.2O) moiety; and R.sub.3 is a hydrocarbon residue with 1 to 20 carbon atoms.

10. The method of claim 8, wherein the nitrogen-containing, adhesion-promoting compound is a compound of formula (III) ##STR00017## wherein: x is the number of repeating monomer units; n is an integer from 1 to 100, and each n in a (CHR.sub.1CHR.sub.2O).sub.n moiety or chain is selected independently of each n in another (CHR.sub.1CHR.sub.2O).sub.n moiety or chain; R.sub.1 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; R.sub.2 is hydrogen or a hydrocarbon residue with 1 to 6 carbon atoms; each R.sub.1 and R.sub.2 in a (CHR.sub.1CHR.sub.2O) moiety is selected independently of each R.sub.1 and R.sub.2 in another (CHR.sub.1CHR.sub.2O) moiety; and R.sub.3 is a hydrocarbon residue with 1 to 20 carbon atoms, and each R.sub.3 in a (NR.sub.3CO) moiety is selected independently of each R.sub.3 in another (NR.sub.3CO) moiety.

11. The method of claim 8, wherein the second solution further comprises a compound selected from sulphinic acid, selenic acid, telluric acid, a heterocyclic compound that comprises at least one sulphur, selenium and/or tellurium atom in the heterocycle, or salt of formula (VIII) ##STR00018## wherein: A is sulfur, selenium, or tellurium; R.sub.9, R.sub.10 and R.sub.11 are each independently alkyl, substituted alkyl, alkenyl, phenyl, substituted phenyl, benzyl, cycloalkyl, or substituted cycloalkyl; and Z.sup. is an anion of an inorganic or organic acid or hydroxide; wherein: the acid of the first solution is different than the sulphinic, selenic or telluric acids selected for the second solution, and the nitrogen-containing, five-membered, heterocyclic compound of first solution contains no sulphur atom, selenium atom or tellurium atom in the heterocycle.

12-15. (canceled)

16. The method of claim 9, wherein R.sub.3 is (CH.sub.2).sub.y and y is an integer from 2 to 12.

17. The method of claim 10, wherein R.sub.3 is (CH.sub.2).sub.y and y is an integer from 2 to 12.

Description

EXAMPLES

[0213] Duraver 104 ML epoxy based 18 m copper layer cladded innerlayer material (manufacturer: Isola) was treated according to the following process sequence.

[0214] At first the samples were treated with a cleaner solution BondFilm Cleaner Alk (Atotech Deutschland GmbH) for 5 min at 50 C. Afterwards the sample was rinsed and etched with an alternative oxide composition according to the formulations in the following examples for 60-70 seconds at 35 C. The treatment time was adjusted in order to have a comparable etch depth of 1.2 m for all test specimen. After rinsing again the sample is dried. The complete set of etched samples showed a brown to dark brown surface cosmetic.

[0215] All samples were laminated in a multilayer press with a Duraver 104 ML epoxy based pre-preg layer according to the material data sheet (manufacturer: Isola). During this procedure the semi cured epoxy prepreg layer is cured and bonded to the treated copper metal surface.

[0216] Finally, the adhesion between the micro roughend copper surface and the epoxy polymer was measured. Peel strength values were measured according to the method described in IPC-TM-650 Test Methods Manual Number 2.4.8 revision C.

Example 1

Comparative Example

[0217] The following aqueous formulation was prepared:

TABLE-US-00006 Benzotriazole 10 g/l Hydrogen peroxide 35% 30 g/l Sulfuric acid 50% 186 g/l Chloride ions 20 mg/l

[0218] A peel strength value of 7.5 N/cm was measured after using a treatment time of 60 seconds and successive lamination of a prepreg layer.

Example 2

[0219] The solution of example 1 was used except that 1.25 g/l N-ethoxylated Polyamide 6, obtainable from -Caprolactamhexaethoxylate monomer, was added to said solution.

[0220] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 9.5 N/cm was measured.

Example 3a

[0221] The solution of example 1 was used except that 0.01 g/l of a tallow amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=40 (Berol 387, Akzo Nobel) was added to said solution.

[0222] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 8.0 N/cm was measured.

Example 3b

[0223] The solution of example 1 was used except that 0.05 g/l of a tallow amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=40 (Berol 387, Akzo Nobel) was added to said solution.

[0224] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 8.3 N/cm was measured.

Example 3c

[0225] The solution of example 1 was used except that 0.1 g/l of a tallow amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=40 (Berol 387, Akzo Nobel) was added to said solution.

[0226] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 8.7 N/cm was measured.

Example 3d

[0227] The solution of example 1 was used except that 0.2 g/l of a tallow amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=40 (Berol 387, Akzo Nobel) was added to said solution.

[0228] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 9.5 N/cm was measured.

Example 3e

[0229] The solution of example 1 was used except that 0.5 g/l of a tallow amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=40 (Berol 387, Akzo Nobel) was added to said solution.

[0230] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 10.3 N/cm was measured.

Example 4

[0231] The solution of example 1 was used except that 0.5 g/l of a hydrogenated tallow alkylamine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=50 (Ethomeen HT/600, Akzo Nobel) was added to said solution.

[0232] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 10.3 N/cm was measured.

Example 5

[0233] The solution of example 1 was used except that 0.5 g/l of a oleylaminethoxylate (a tertiary amine based on a primary oleyl amine having a residue according to formula (I) with R.sub.1 and R.sub.2=hydrogen and n=12) (Ethomeen OV/22, Akzo Nobel) was added to said solution.

[0234] After using a treatment time of 70 seconds and successive lamination of a prepreg layer a peel strength value of 9.4 N/cm was measured.

Example 6

[0235] A sample treated with a solution according to example 1 was then immersed into an aqueous post dip solution of 1.25 g N-ethoxylated Polyamide 6, obtainable from -Caprolactamhexaethoxylate for 30 seconds at 25 C.

[0236] After successive lamination of a prepreg layer a peel strength value of 8.9 N/cm was measured.

Example 7

[0237] A sample treated with a solution according to example 1 was then immersed into an aqueous post dip solution of 0.2 g N-ethoxylated Polyamide 6, obtainable from -Caprolactamhexaethoxylate for 30 seconds at 25 C.

[0238] After successive lamination of a prepreg layer a peel strength value of 8.3 N/cm was measured.