Donald J Swanson

US Patent:

6444189, Sep 3, 2002

Filed:

Apr 26, 2000

Appl. No.:

09/558050

Inventors:

Ying Wang - Wilmington DE
Donald Keith Swanson - Neshanic Station NJ

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

C01G 23047

US Classification:

423610, 423612

Abstract:

Titanium oxide particles are prepared from the reaction of an aqueous basic solution with ( ) an aqueous acidic titanium salt solution, or ( ) an aqueous salt solution of a titanium salt and an aqueous salt solution of a dopant metal salt. In preferred embodiments, the particles may range in size from to microns ( meters), and possess relatively high bulk density combined with high surface area.

US Patent:

57888876, Aug 4, 1998

Filed:

Nov 1, 1996

Appl. No.:

8/709561

Inventors:

Donald Keith Swanson - Wilmington DE

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

H01B 108

US Classification:

2525201

Abstract:

Antimony doped tin oxide powder having an open pore structure wherein the pore volume is at least 0. 005 cc/g for any mean pore diameter within the range of 0. 1 to 8 micrometers is disclosed.

US Patent:

55188087, May 21, 1996

Filed:

Nov 5, 1993

Appl. No.:

8/148734

Inventors:

Salvatore A. Bruno - Wilmington DE
Donald K. Swanson - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

B32B 516
C09K 1108

US Classification:

428323

Abstract:

The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0. 5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. The composition can be employed to form a luminescent film or layer within a plasma display panel.

US Patent:

53824520, Jan 17, 1995

Filed:

Feb 25, 1994

Appl. No.:

8/202867

Inventors:

Salvatore A. Bruno - Wilmington DE
Donald K. Swanson - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

B05D 700

US Classification:

427215

Abstract:

The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0. 5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. One aspect the invention relates to a process for preparing the composition which comprises decomposing chelated metal luminescent compositions in solution at a relatively high pH while in the presence of dispersed core particles, thereby coating the core particles with hydrous metal oxides, recovering the coated particles, optionally washing the coated particles substantially free from soluble species, drying and calcining. In another aspect, a hydrous oxide coating is converted to a sulfide coating by treating the hydrous coating with a source of active sulfur. In yet another aspect, the invention relates to adding an acidic solution of metal oxides along with a solution of oxalic acid to a slurry of dispersed core particles which become coated with the metal oxalates, recovering the product, washing the coated particles substantially free from soluble species, drying the oxalate composition.

US Patent:

50860216, Feb 4, 1992

Filed:

Jun 28, 1990

Appl. No.:

7/545249

Inventors:

Kyoichi Sasaki - Tokyo, JP
Donald K. Swanson - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C04B 3546

US Classification:

501137

Abstract:

A dielectric ceramic powder composition for forming multilayer ceramic devices having thin dielectric layers with low porosity and having a dissipation factor which meets or exceeds X7R specifications, and consisting essentially of an admixture of a major component ceramic powder particle and minor component additives the amounts of which are controlled within certain predetermined ratios.

US Patent:

56436742, Jul 1, 1997

Filed:

Jun 1, 1993

Appl. No.:

8/067402

Inventors:

Salvatore Anthony Bruno - Wilmington DE
Donald Keith Swanson - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

B32B 900
H01J 2900

US Classification:

428403

Abstract:

The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0. 5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. One aspect the invention relates to a process for preparing the composition which comprises decomposing chelated metal luminescent precursors in solution at a relatively high pH while in the presence of dispersed core particles, thereby coating the core particles with hydrous metal oxides, recovering the coated particles, washing the coated particles substantially free from soluble species, drying and calcining. In another aspect, a hydrous oxide coating is converted to a sulfide coating by treating the hydrous coating with a source of active sulfur. In yet another aspect, the invention relates to adding an acidic solution of metal oxides along with a solution of oxalic acid to a slurry of dispersed core particles which become coated with the metal oxalates, recovering the product, washing the coated particles substantially free from soluble species, drying the oxalate composition.

US Patent:

58611347, Jan 19, 1999

Filed:

Jun 9, 1997

Appl. No.:

8/871162

Inventors:

Donald Keith Swanson - Wilmington DE

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

C01B 33113
C03C 1100

US Classification:

423335

Abstract:

Internal porosity is created in dense SiO. sub. 2 particles by heating a mixture of the particles with B. sub. 2 O. sub. 3 above the melting point of both mixture components. Resulting SiO. sub. 2 particles have altered morphology, internal porosity, and a negative thermal expansion coefficient when heated.

US Patent:

57889139, Aug 4, 1998

Filed:

Nov 1, 1996

Appl. No.:

8/742614

Inventors:

Donald Keith Swanson - Wilmington DE

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

H01B 108
C01G 1902
C01G 3000
C01B 1336

US Classification:

2525201

Abstract:

Solution precipitation processes for preparing antimony doped tin oxide having improved volumetric efficiency and improved wash efficiency involving use of concentrated base and metal salt solutions are disclosed.