Ashish Dubey

US Patent:

6641658, Nov 4, 2003

Filed:

Jul 3, 2002

Appl. No.:

10/189879

Inventors:

Ashish Dubey - Grayslake IL

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

C04B 1806

US Classification:

106705, 106695, 106696, 106772, 106773, 106774, 106819, 106823, 106706, 106707, 106708

Abstract:

A rapid setting cementitious composition useful for making cement boards employs an insoluble form of anhydrous calcium sulfate (anhydrite) to accelerate setting and to permit reducing the amount of high alumina cement usage.

US Patent:

6869474, Mar 22, 2005

Filed:

Apr 16, 2003

Appl. No.:

10/414686

Inventors:

Marianela Perez-Pena - Grayslake IL, US
Ashish Dubey - Grayslake IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

C04B024/12

US Classification:

106727, 106819, 106823

Abstract:

Extremely fast setting of cementitious compositions for producing cement-based products such as cement boards is made possible by adding an alkanolamine to a hydraulic cement such as portland cement, and forming a slurry with water under conditions that provide an initial slurry temperature of at least 90 F. Use of alkanolamine under conditions disclosed herein allows an extremely rapid setting of the cementitious composition. Additional reactive materials may be included such as high alumina cement, calcium sulfate and a pozzolanic material such as fly ash. The extremely fast rapid set permits rapid production of cementitious products.

US Patent:

6986812, Jan 17, 2006

Filed:

Sep 18, 2003

Appl. No.:

10/664460

Inventors:

Ashish Dubey - Grayslake IL, US
Michael J. Porter - Hanover Park IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

B05C 1/08

US Classification:

118259, 118262, 118304, 156346

Abstract:

A feed apparatus for use in depositing a slurry upon a moving web having a direction of travel includes a main metering roll, a companion roll disposed in closely spaced relation to the metering roll to form a nip therebetween. The nip is constructed and arranged to retain a supply of the slurry, and the rolls are driven so that slurry retained in the nip progresses over an upper outer peripheral surface of the metering roll to be deposited upon the web. Also preferably included is a thickness control roll disposed in operational relationship to the metering roll for controlling thickness of a layer of slurry drawn from the nip over the outer metering roll surface. Preferably, the metering roll, the companion roll and the thickness control roll are driven in the same direction.

US Patent:

7347895, Mar 25, 2008

Filed:

Sep 12, 2005

Appl. No.:

11/224403

Inventors:

Ashish Dubey - Grayslake IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

C04B 18/06

US Classification:

106705, 106DIG 1

Abstract:

A composition for making flexible articles includes a hydraulic component of at least 50 weight % fly ash, a water-soluble, film-forming polymer and water. Articles are made from this composition by making a slurry of the components, forming the article and allowing it to set.

US Patent:

7445738, Nov 4, 2008

Filed:

Sep 18, 2003

Appl. No.:

10/666294

Inventors:

Ashish Dubey - Grayslake IL, US
Joe W. Chambers - Lake Geneva WI, US
Aaron Greengard - McHenry IL, US
Alfred C. Li - Naperville IL, US
D. Paul Miller - Lindenhurst IL, US
Michael J. Porter - Hanover Park IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

B29C 70/06
B29C 70/30

US Classification:

264128, 264308, 264333, 26417219, 156 42

Abstract:

A multi-layer process for producing structural cementitious panels, includes, a. providing a moving web; b. one of depositing a first layer of loose fibers upon the web and c. depositing a layer of settable slurry upon the web; d. depositing a second layer of loose fibers upon the slurry; e. embedding said second layer of fibers into the slurry; and f. repeating steps c. through e. until the desired number of layers of settable fiber-enhanced slurry in the panel is obtained. Also provided are a structural panel produced by the present process, an apparatus suitable for producing structural cementitious panels according to the present process, and a structural cementitious panel having multiple layers, each layer created by depositing a layer of settable slurry upon a moving web, depositing fibers upon the slurry and embedding the fibers into the slurry such that each layer is integrally formed with the adjacent layers.

US Patent:

7468154, Dec 23, 2008

Filed:

Sep 12, 2007

Appl. No.:

11/900495

Inventors:

Ashish Dubey - Grayslake IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

B28B 3/00

US Classification:

264333, 264DIG 49, 428 15, 428414, 106705, 106DIG 1

Abstract:

A composition for making flexible articles includes a hydraulic component of at least 50 weight % fly ash, a water-soluble, film-forming polymer and water. Articles are made from this composition by making a slurry of the components, forming the article and allowing it to set.

US Patent:

7670520, Mar 2, 2010

Filed:

Nov 1, 2006

Appl. No.:

11/591793

Inventors:

Ashish Dubey - Grayslake IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

B29C 70/06
B29C 70/30

US Classification:

264128, 264308, 264333, 26417219, 156 42

Abstract:

A process for producing fiber-reinforced structural cementitious panels made of at least one layer of fiber reinforced cementitious slurry, the process for each such layer of slurry including providing a moving web; depositing a first layer of individual, loose fibers upon the web; depositing a layer of settable slurry upon the deposited first layer of individual, loose fibers; depositing a second layer of individual, loose fibers upon the deposited layer of settable slurry; and actively embedding both layers of individual, loose fibers into the layer of slurry to distribute the fibers throughout the slurry.

US Patent:

7732032, Jun 8, 2010

Filed:

Dec 30, 2004

Appl. No.:

11/025850

Inventors:

Ashish Dubey - Grayslake IL, US

Assignee:

United States Gypsum Company - Chicago IL

International Classification:

C04B 16/00
C04B 20/00
C04B 38/00

US Classification:

428 57, 106672, 428 58, 428 60, 428192

Abstract:

Lightweight, fiber reinforced, cementitious panels possessing exceptional toughness for use as building components in applications such as roofing elements, siding elements, framing and sheathing elements, and substrate elements for installation of floor finishes in residential and other building construction types. The panels employ a continuous phase resulting from the curing of an aqueous mixture of inorganic binder, PVA fibers and lightweight filler. The inorganic binder may be, for example, hydraulic cement alone, or a combination of hydraulic cement and pozzolan/s, or a combination of hydraulic cement, alpha hemihydrate, active pozzolan and optionally lime. The PVA fibers reinforce the continuous phase and are randomly distributed throughout the composite. Typical panels of the invention have a density of 60-85 pcf.