Veeriya V Rajasekaran from 200 Dothan Ct, Greenville, SC 29607, age 83, Phone: (864)2881789

Process Of Preparing A Solid Electrolytic Capacitor Containing A Conductive Polymer Counter Electrode
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US Patent:

6391379, May 21, 2002
Filed:

Sep 4, 1998
Appl. No.:

09/148486
Inventors:

Philip M. Lessner - Simpsonville SC
Tsung-Yuan Su - Greer SC
Brian J. Melody - Greer SC
John T. Kinard - Simpsonville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

B05D 512
US Classification:

427 80, 29 2503
Abstract:

The present invention relates to a method for making a solid electrolytic capacitor having a low equivalent series resistance by impregnating a porous capacitor pellet with conductive polymer. An oxidized pellet is dipped in a high concentration conductive polymer solution to deposit the polymer in doped (conductive) form. The solution also contains a crosslinking agent to prevent redissolution of the polymer when the pellet is re-dipped. After dipping, the solvent in the polymer solution is evaporated and a conductive film formed. In order to evaporate the solvent quickly, the solvent should have a boiling point of 80-220Â C. and preferably a boiling point of 100-150Â C. The conductive polymer film has a low resistivity (less than 1 ohm-cm, preferably less than 0. 2 ohm-cm).

Preparation Of Conductive Polymers From Stabilized Precursor Solutions
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US Patent:

60568992, May 2, 2000
Filed:

May 28, 1999
Appl. No.:

9/321740
Inventors:

Philip M. Lessner - Simpsonville SC
Tsung-Yuan Su - Greer SC
Randolph S. Hahn - Greenville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

H01B 106
US Classification:

2525181
Abstract:

Conductive polymers are prepared from a stabilized solution containing a monomer, an Fe(III) oxidizing agent, and a mixed solvent. The solvents are selected to stabilize the Fe(III) oxidizing agent and monomer in solution while allowing highly conducting polymers to be produced upon evaporating the lower-boiling solvent. The higher-boiling solvent does not appreciably complex with Fe(III), while the lower-boiling solvent forms a weak complex with Fe(III). The mixed-solvent system of the present invention may be used for preparing a conductive polymer counter electrode in a solid tantalum capacitor by polymerizing the monomer inside a porous tantalum pellet.

Process For Improving Leakage And Dissipation Factor Of Solid Electrolytic Capacitors Employing Conductive Polymer Cathodes
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US Patent:

61910139, Feb 20, 2001
Filed:

Dec 16, 1999
Appl. No.:

9/461428
Inventors:

Randolph S. Hahn - Greensville SC
Philip M. Lessner - Simpsonville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

H01L 21265
US Classification:

438523
Abstract:

The adhesion of a conductive polymer film to an oxidized porous pellet anode is improved by the incorporation of a silane coupling agent in the polymer impregnating solution. The incorporation of the silane coupling agent also decreases leakage current and dissipation factor. Suitable silanes are those of the general formula (R. sup. 1 --R. sup. 3)--Si--(OR. sup. 2). sub. 3. Each of R. sup. 2 and R. sup. 3 is a C. sub. 1 -C. sub. 6 alkyl group such as methyl, ethyl, or propyl R. sup. 1 can be chosen from a wide variety of organic functional groups such as epoxy, glycidoxy, amino, and pyrrole. The most preferred silane is 3-glycidoxypropyltrimethoxysilane.

Preparation Of Conductive Polymers From Stabilized Precursor Solutions
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US Patent:

61363723, Oct 24, 2000
Filed:

Nov 10, 1999
Appl. No.:

9/438060
Inventors:

Philip M. Lessner - Simpsonville SC
Tsung-Yuan Su - Greer SC
Randolph S. Hahn - Freenville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

H01B 100
US Classification:

4272133
Abstract:

Conductive polymers are prepared from a stabilized solution containing a monomer, an Fe(III) oxidizing agent, and a mixed solvent. The solvents are selected to stabilize the Fe(III) oxidizing agent and monomer in solution while allowing highly conducting polymers to be produced upon evaporating the lower-boiling solvent. The higher-boiling solvent does not appreciably complex with Fe(III), while the lower-boiling solvent forms a weak complex with Fe(III). The mixed-solvent system of the present invention may be used for preparing a conductive polymer counter electrode in a solid tantalum capacitor by polymerizing the monomer inside a porous tantalum pellet.

Electrolytic Capacitor With Improved Leakage And Dissipation Factor
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US Patent:

60726946, Jun 6, 2000
Filed:

Sep 30, 1998
Appl. No.:

9/163318
Inventors:

Randolph S. Hahn - Greensville SC
Philip M. Lessner - Simpsonville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

H01G 915
US Classification:

361523
Abstract:

The adhesion of a conductive polymer film to an oxidized porous pellet anode is improved by the incorporation of a silane coupling agent in the polymer impregnating solution. The incorporation of the silane coupling agent also decreases leakage current and dissipation factor. Suitable silanes are those of the general formula (R. sup. 1 --R. sup. 3)--Si--(OR. sup. 2). sub. 3. Each of R. sup. 2 and R. sup. 3 is a C. sub. 1 -C. sub. 6 alkyl group such as methyl, ethyl, or propyl. R. sup. 1 can be chosen from a wide variety of organic functional groups such as epoxy, glycidoxy, amino, and pyrrole. The most preferred silane is 3-glycidoxypropyltrimethoxysilane.

Preparation Of Conductive Polymers From Stabilized Precursor Solutions
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US Patent:

60012811, Dec 14, 1999
Filed:

Sep 4, 1998
Appl. No.:

9/148484
Inventors:

Philip M. Lessner - Simpsonville SC
Tsung-Yuan Su - Greer SC
Randolph S. Hahn - Greenville SC
Veeriya Rajasekaran - Greenville SC
Assignee:

Kemet Electronics Corporation - Greenville SC
International Classification:

H01B 100
US Classification:

252500
Abstract:

Conductive polymers are prepared from a stabilized solution containing a monomer, an Fe(III) oxidizing agent, and a mixed solvent. The solvents are selected to stabilize the Fe(III) oxidizing agent and monomer in solution while allowing highly conducting polymers to be produced upon evaporating the lower-boiling solvent. The higher-boiling solvent does not appreciably complex with Fe(III), while the lower-boiling solvent forms a weak complex with Fe(III). The mixed-solvent system of the present invention may be used for preparing a conductive polymer counter electrode in a solid tantalum capacitor by polymerizing the monomer inside a porous tantalum pellet.

Veeriya V Rajasekaran