Direct electrolytic metallization on non-conducting substrates
View Patent ↗The invention relates to a method for the direct electrolytic metallization of electrically non-conducting substrate surfaces comprising bringing the substrate surfaces into contact with a water-soluble polymer; treating the substrate surfaces with a permanganate solution; treating the substrate surfaces with an acidic aqueous solution or an acidic microemulsion of aqueous base containing at least one thiophene compound and at least one alkane sulfonic acid selected from the group comprising methane sulfonic acid, ethane sulfonic acid and ethane disulfonic acid; electrolytically metallizing the substrate surfaces.
1. Method for the direct electrolytic metallization of electrically non-conducting substrates, comprising:
a. bringing the substrate surfaces into contact with a water soluble polymer;
b. treating the substrate surfaces with a permanganate solution after contacting the substrate surfaces with the water soluble polymer of step a;
c. after treating of the substrate surfaces with the permanganate solution in step b, treating the substrate surfaces with an acidic aqueous solution
or an acidic microemulsion of aqueous base containing at least one thiophene compound and at least one alkane sulfonic acid selected from the group consisting of methane sulfonic acid, ethane sulfonic acid and ethane disulfonic acid; and
d. electrolytically metallizing the substrate surfaces after treating the substrate surfaces in step c.
2. The method of claim 1 , wherein, the permanganate solution is acidic.
3. The method of claim 2 , wherein, the permanganate solution is adjusted to a pH ranging from 3.5 to 5.
4. The method of claim 1 , wherein, the permanganate solution is adjusted to a pH ranging from 2.5 to 7.
5. The method of claim 1 , wherein, the permanganate solution comprises at least one buffer compound for adjusting the pH-value, said buffer compound being selected from the group consisting of phosphoric acid, dihydrogen phosphate and hydrogen phosphate.
6. The method of claim 1 , wherein, the permanganate solution comprises at least one buffer compound for adjusting the pH-value, said buffer compound being selected from the group consisting of boric acid and borate.
7. The method of claim 1 , wherein, the at least one alkane sulfonic acid is methane sulfonic acid.
8. The method of claim 1 , wherein, by adjusting the concentration of the at least one alkane sulfonic acid, the pH of the solution or microemulsion is in the range of 0 to 3.
9. The method of claim 1 , wherein, by adjusting the concentration of the at least one alkane sulfonic acid, the pH of the solution or microemulsion is in the range of 1.5 to 2.1.
10. The method of claim 1 , wherein, the at least one thiophene compound is selected from the group consisting of 3-heterosubstituted thiophenes and 3,4-diheterosubstituted thiophenes.
11. The method of claim 1 , wherein, the at least one thiophene compound is selected from the group consisting of 3,4-ethylene dioxythiophene, 3-methoxy thiophene, 3-methyl-4-methoxy thiophene and the derivatives thereof.
12. The method of claim 1 , wherein, said solution or microemulsion furthermore contains at least one surfactant.
13. The method of claim 12 , wherein the at least one surfactant is an ethoxylate surfactant.
14. The method of claim 1 , wherein, said solution or microemulsion furthermore contains at least one salt of the at least one alkane sulfonic acid.
15. The method of claim 1 , wherein, the substrate surfaces are electrolytically copper-plated in method step d.
16. Method for the direct electrolytic metallization of electrically non-conducting substrates, comprising:
a. bringing the substrate surfaces into contact with a water soluble polymer;
b. treating the substrate surfaces with a permanganate solution after contacting the substrate surfaces with the water soluble polymer of step a;
c. after treating of the substrate surfaces with the permanganate solution in step b,
treating the substrate surfaces with an acidic aqueous solution or an acidic microemulsion of aqueous base containing at least one thiophene compound and at least one alkane sulfonic acid selected from the group consisting of methane sulfonic acid, ethane sulfonic acid and ethane disulfonic acid; and
d. electrolytically metallizing the substrate surfaces after treating the substrate surfaces in step c;
e. wherein the permanganate solution is adjusted to a pH ranging from 2.5 to 7; and
f. wherein the permanganate solution comprises at least one buffer compound for adjusting the pH-value, said buffer compound being selected from the group consisting of phosphoric acid, dihydrogen phosphate and hydrogen phosphate;
g. wherein the at least one alkane sulfonic acid is methane sulfonic acid;
h. wherein said solution or microemulsion furthermore contains at least one surfactant; and
i. wherein the at least one surfactant is an ethoxylate surfactant.
17. Method for the direct electrolytic metallization of electrically non-conducting substrates, comprising:
a. bringing the substrate surfaces into contact with a water soluble polymer;
b. treating the substrate surfaces with a permanganate solution after contacting the substrate surfaces with the water soluble polymer of step a;
c. after treating of the substrate surfaces with the permanganate solution in step b,
treating the substrate surfaces with an acidic aqueous solution or an acidic microemulsion of aqueous base containing at least one thiophene compound and at least one alkane sulfonic acid selected from the group consisting of methane sulfonic acid, ethane sulfonic acid and ethane disulfonic acid; and
d. electrolytically metallizing the substrate surfaces after treating the substrate surfaces in step c;
e. wherein the permanganate solution is adjusted to a pH ranging from 2.5 to 7; and
f. wherein the at least one thiophene compound is selected from the group consisting of 3-heterosubstituted thiophenes and 3,4-diheterosubstituted thiophenes.
18. The method of claim 17 , wherein said solution or microemulsion furthermore contains at least one surfactant.
19. The method of claim 17 , wherein said solution or microemulsion furthermore contains at least one salt of the at least one alkane sulfonic acid.
20. Method for the direct electrolytic metallization of electrically non-conducting substrates, comprising:
a. bringing the substrate surfaces into contact with a water soluble polymer;
b. treating the substrate surfaces with a permanganate solution after contacting the substrate surfaces with the water soluble polymer of step a;
c. after treating of the substrate surfaces with the permanganate solution in step b,
treating the substrate surfaces with an acidic aqueous solution or an acidic microemulsion of aqueous base containing at least one thiophene compound and at least one alkane sulfonic acid selected from the group consisting of methane sulfonic acid, and ethane sulfonic acid and ethane disulfonic acid;
d. electrolytically metallizing the substrate surfaces after treating the substrate surfaces in step c;
e. wherein the permanganate solution comprises at least one buffer compound for adjusting the pH-value, said buffer compound being selected from the group consisting of boric acid and borate; and
f. wherein by adjusting the concentration of the at least one alkane sulfonic acid, the pH of the solution or microemulsion is in the range of 0 to 3.