Process for cathodic protection of electrode material

• US 8,034,229 B2
• Filed: 02/18/2010
• Issued: 10/11/2011
• Est. Priority Date: 07/26/2006
• Status: Active Grant

• Current Assignee: Cortigent Incorporated
• Original Assignee: Second Sight Medical Products, Inc.
• Inventors: Hines, Amy, Greenberg, Robert J., Zhou, Dao Min, Little, James Singleton
• Primary Examiner(s): BELL, BRUCE F
• Application Number:
  US12/708,358
• Publication Number:
  US 20100147702A1
• Time in Patent Office: 600 Days
• Field of Search: 205/740, 205/724, 205/725, 205/726, 205/727, 128/897, 600/300
• US Class Current: 205/740
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: C23F 13/00 Inhibiting corrosion of metals by anodic or cathodic protection
• CPC Class Codes: C23F 13/02 cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions

Abstract

The invention is a process for cathodic protection of electrodes wherein negative bias is applied on the electrode. The negative bias is obtained by asymmetric current pulse, which is obtained by negative phase pulsing with higher amplitude than that of the anodic phase. The asymmetric current pulse is obtained by negative phase pulsing with wider pulse width than that of the anodic phase. The asymmetric current pulse may also be obtained by negative phase pulsing with both higher amplitude and wider pulse width than that of the anodic phase. The invention further relates to a process for cathodic protection of electrodes, wherein negative bias is applied on the electrode, and the negative bias is obtained by asymmetric current pulse, where the asymmetric current pulse is obtained by negative phase pulsing with wider pulse width than that of the anodic phase. The wider pulse width is obtained by pulse trains.

Claims

1. A process for cathodic protection of an electrode wherein:

negative and positive asymmetric biphasic current pulse trains with a negative bias are applied to said electrode; and

said asymmetric current pulse trains are obtained by performing said negative phase with wider pulse width than that of an anodic phase.

2. The process according to claim 1, wherein said negative bias is obtained by providing more negative current pulses than positive current pulses.

3. The process according to claim 1 wherein said negative pulses provide greater charge from 1-15%.

4. The process according to claim 1 wherein said negative pulses provide greater charge from 3-7%.

5. The process according to claim 1 wherein said negative pulses provide greater charge from 4-6%.

6. The process according to claim 1 wherein said electrodes are comprised of Pt, Pd, Ti, TiN, Nb, Rh, Ir, Au, or W, their oxides or alloys thereof.

7. The process according to claim 1, wherein said electrodes are biocompatible.

8. The process according to claim 1, wherein said electrodes are suitable to stimulate neural tissue.

9. The process according to claim 1, wherein said negative bias is limited to keep a voltage excursion within a water widow.