David G Midkiff

US Patent:

6365088, Apr 2, 2002

Filed:

Jun 24, 1999

Appl. No.:

09/339761

Inventors:

Preston Biggers Knight - Corinth MS
David Lewis Myers - Cumming GA
John Joseph Lassig - Lawrenceville GA
David Grant Midkiff - Alpharetta GA
Rick Leon Busby - Marietta GA
Anthony Lee Lamanac - Woodstock GA
Leonid Anthony Turkevich - Alpharetta GA

Assignee:

Kimberly-Clark Worldwide, Inc. - Neenah WI

International Classification:

H05F 300

US Classification:

264436, 246438, 246484, 4251748 E

Abstract:

The process of forming an electret nonwoven web, the process including the steps of providing a nonwoven web, generating a DC corona discharge from an apparatus including an anode electrically configured as a parallel device, and subjecting the web to DC corona discharge to form an electret.

US Patent:

6573205, Jun 3, 2003

Filed:

Jan 27, 2000

Appl. No.:

09/492607

Inventors:

David Lewis Myers - Cumming GA
John Joseph Lassig - Lawrenceville GA
Leonid Anthony Turkevich - Alpharetta GA
David Grant Midkiff - Alpharetta GA

Assignee:

Kimberly-Clark Worldwide, Inc. - Neenah WI

International Classification:

H01G 702

US Classification:

442414, 442221, 442286, 442301, 442370, 442381, 442394, 442400, 442401, 442408, 428131, 4283044, 428323, 428372, 428500, 55DIG 39, 307400

Abstract:

A porous polymeric sheet is provided having an electrostatic charge and comprising a zero-three composite of a polymeric matrix and a ferroelectric material dispersed therein. The polymeric component comprises a non-polar thermoplastic polymer, such as a polyolefin, and a second thermoplastic polymer having polar functional units, such as a telomer. The composite material is formed into a porous sheet and is electrically or corona poled to create an electret material which is well suited four use in various filtration, air-masking and dust wipe applications.

US Patent:

6893990, May 17, 2005

Filed:

Apr 8, 2003

Appl. No.:

10/409813

Inventors:

David Lewis Myers - Cumming GA, US
John Joseph Lassig - Lawrenceville GA, US
Leonid Anthony Turkevich - Alpharetta GA, US
David Grant Midkiff - Alpharetta GA, US

Assignee:

Kimberly Clark Worldwide, Inc. - Neenah WI

International Classification:

H01G007/02
B03C003/28
D01F006/04
D04H001/00
D04H003/00

US Classification:

442414, 442221, 442286, 442301, 442370, 442381, 442394, 442400, 442401, 442408, 428131, 4283044, 428323, 428372, 428500, 55DIG 39, 307400

Abstract:

A porous polymeric sheet is provided having an electrostatic charge and comprising a zero-three composite of a polymeric matrix and a ferroelectric material dispersed therein. The polymeric component comprises a non-polar thermoplastic polymer, such as a polyolefin, and a second thermoplastic polymer having polar functional units, such as a telomer. The composite material is formed into a porous sheet and is electrically or corona poled to create an electret material which is well suited four use in various filtration, air-masking and dust wipe applications.

US Patent:

7642208, Jan 5, 2010

Filed:

Dec 14, 2006

Appl. No.:

11/638862

Inventors:

Jeffrey Lawrence McManus - Canton GA, US
David Grant Midkiff - Alpharetta GA, US

Assignee:

Kimberly-Clark Worldwide, Inc. - Neenah WI

International Classification:

B32B 5/26
D04H 1/00

US Classification:

442382, 442381, 442361, 442362, 442363, 442364, 442365, 4282967

Abstract:

A composite polymeric material is provided that may be used to construct an abrasion resistant layer or sheet such as an abrasion resistant meltblown layer. Desirably, the composite polymeric material comprises blends of syndiotactic and isotactic polypropylene with ferroelectric materials. The composite polymeric material is particularly useful for constructing a filter media comprising an abrasion resistant fine fiber layer such as a nonwoven layer. The composite polymeric material of the present invention also allows for electret treatment to improve its filtration characteristics.

US Patent:

20030045192, Mar 6, 2003

Filed:

Aug 31, 2001

Appl. No.:

09/944435

Inventors:

David Midkiff - Alpharetta GA, US
Michael Gross - Atlanta GA, US
Billy Arnold - Alpharetta GA, US
Sandy Tan - Roswell GA, US

Assignee:

Kimberly-Clark Worldwide

International Classification:

B32B003/06
B32B005/02
B32B009/00
D06N007/04

US Classification:

442/103000, 442/340000, 442/417000, 442/381000, 442/149000, 428/152000

Abstract:

The present invention relates to a composite structure which is capable of use as a filter medium and a method for producing the same. The composite structure contains at least a first nonwoven layer, said first layer having a first surface and a second surface, as well as a rigidifying or stiffening component. The rigidifying component is applied in semi-molten state to the one surface of the nonwoven layer and provides sufficient stiffness and/or resilience to the composite such that the composite is self-pleatable yet retains flexibility. The rigidifying or stiffening component may be filaments of a polymer or polymer blend or alternatively the rigidifying or stiffening component may also be a wax or wax blend.

US Patent:

20100326902, Dec 30, 2010

Filed:

Jun 29, 2009

Appl. No.:

12/493276

Inventors:

David Grant Midkiff - Alpharetta GA, US
Heather M. Richmond - Rosewell GA, US
Nina Frazier - Mableton GA, US

International Classification:

B01D 39/16
D04H 13/00

US Classification:

210490, 4284111, 428523

Abstract:

The present invention provides a multilayer web having at least a first layer and a second layer. The second layer attached to the first layer and the second layer comprising fibers produced from polymeric composition comprising a blend of a thermoplastic polymeric component and a functionalized polymeric component. The functionalized polymeric component is at least 26% by weight of the polymeric components of the second layer. The multilayer web is particularly suited for filtration media.

US Patent:

57077355, Jan 13, 1998

Filed:

Mar 18, 1996

Appl. No.:

8/617005

Inventors:

David Grant Midkiff - Alpharetta GA
Samuel Edward Marmon - Alpharetta GA

International Classification:

D02G 300

US Classification:

428373

Abstract:

A conjugate multilobal fiber and a fabric made therefrom is provided. The fiber comprises at least two polymers arranged with at least one polymer occupying a portion of the fiber and at least one other polymer having a lower melting point than the first portion polymer occupying an outer portion of the fiber. The polymers can be arranged in a number of configurations depending on the planned use of the web.

US Patent:

56675623, Sep 16, 1997

Filed:

Apr 19, 1996

Appl. No.:

8/633979

Inventors:

David Grant Midkiff - Alpharetta GA

Assignee:

Kimberly-Clark Worldwide, Inc. - Irving TX

International Classification:

B03C 3155

US Classification:

96 15

Abstract:

There is provided a vacuum cleaner filter medium which is a nonwoven spunbond web of conjugate spunbond fibers. The web has a Frazier permeability of at least 250 CFM, an NaCI efficiency of at least 65 percent, a Gurley Stiffness of at least 20 mg, and a pressure drop of 0. 5 or less mm H. sub. 2 O. The conjugate fibers are made from polymers, more particularly polyolefins, still more particularly polypropylene and polyethylene in a side-by-side configuration. The filter medium is treated by a hot-air knife and through-air bonded during the production process. The medium is also electret treated. The medium has sufficient stiffness to be converted into a filter by conventional techniques. While this invention is directed mainly to air purification and filtration, other gasses may be filtered as well.