Plastic and nonmetallic article shaping or treating: processes – Direct application of fluid pressure differential to... – Production of continuous or running length
Reexamination Certificate
2002-06-20
2004-11-30
Tentoni, Leo B. (Department: 1732)
Plastic and nonmetallic article shaping or treating: processes
Direct application of fluid pressure differential to...
Production of continuous or running length
C264S103000, C425S072200, C425S382200, C425S463000
Reexamination Certificate
active
06824733
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to devices and methods for preparing melt blown fibers.
BACKGROUND
Nonwoven webs typically are formed using a meltblowing process in which filaments are extruded from a series of small orifices while being attenuated into fibers using hot air or other attenuating fluid. The attenuated fibers are formed into a web on a remotely-located collector or other suitable surface. A spun bond process can also be used to form nonwoven webs. Spun bond nonwoven webs typically are formed by extruding molten filaments from a series of small orifices, exposing the filaments to a quench air treatment that solidifies at least the surface of the filaments, attenuating the at least partially solidified filaments into fibers using air or other fluid and collecting and optionally calendaring the fibers into a web. Spun bond nonwoven webs typically have less loft and greater stiffness than melt blown nonwoven webs, and the filaments for spun bond webs typically are extruded at lower temperatures than for melt blown webs.
There has been an ongoing effort to improve the uniformity of nonwoven webs. Web uniformity typically is evaluated based on factors such as basis weight, average fiber diameter, web thickness or porosity. Process variables such as material throughput, air flow rate, die to collector distance, and the like can be altered or controlled to improve nonwoven web uniformity. In addition, changes can be made in the design of the meltblowing or spun bond apparatus. References describing such measures include U.S. Pat. Nos. 4,889,476, 5,236,641, 5,248,247, 5,260,003, 5,582,907, 5,728,407, 5,891,482 and 5,993,943.
An extruder and one or more metering gear pumps generally are used to supply fiber-forming material to a meltblowing die. The gear pump typically has two counter-rotating meshed gears. Wide melt blown nonwoven webs have been formed by arranging a plurality of meltblowing dies in a side-by-side array, and by using a plurality of such gear pumps to deliver molten polymer to the array of dies, see U.S. Pat. Nos. 5,236,641 and 6,182,732. The '641 patent utilizes sensors and a feedback system to measure a physical property (e.g., thickness or basis weight) of strips of the web, and then alters the speeds of the gear pumps to maintain uniformity of the selected property within the strips or across the width of the web.
Despite many years of effort by various researchers, fabrication of commercially suitable nonwoven webs still requires careful adjustment of the process variables and apparatus parameters, and frequently requires that trial and error runs be performed in order to obtain satisfactory results. Fabrication of wide melt blown nonwoven webs with uniform properties can be especially difficult.
REFERENCES:
patent: 3498230 (1970-03-01), Schippers
patent: 3502033 (1970-03-01), Kaczorowski
patent: 3571679 (1971-03-01), Van Turnhout
patent: 3971373 (1976-07-01), Braun
patent: 4111531 (1978-09-01), Lavelle et al.
patent: 4215682 (1980-08-01), Kubik et al.
patent: 4889476 (1989-12-01), Buehning
patent: 4995333 (1991-02-01), Keller et al.
patent: 5124111 (1992-06-01), Keller et al.
patent: 5236641 (1993-08-01), Allen et al.
patent: 5248247 (1993-09-01), Rübhausen et al.
patent: 5260003 (1993-11-01), Nyssen et al.
patent: 5354529 (1994-10-01), Berger et al.
patent: 5458291 (1995-10-01), Brusko et al.
patent: 5582907 (1996-12-01), Pall
patent: 5605720 (1997-02-01), Allen et al.
patent: 5636790 (1997-06-01), Brusko et al.
patent: 5637331 (1997-06-01), Lenk et al.
patent: 5728407 (1998-03-01), Matsui
patent: 5863485 (1999-01-01), Groleau
patent: 5863565 (1999-01-01), Rossillon et al.
patent: 5891482 (1999-04-01), Choi
patent: 5902531 (1999-05-01), Berger et al.
patent: 5951942 (1999-09-01), Rossillon et al.
patent: 5993943 (1999-11-01), Bodaghi et al.
patent: 6057256 (2000-05-01), Krueger et al.
patent: 6182732 (2001-02-01), Allen
patent: 6296463 (2001-10-01), Allen
patent: 29 33 025 (1981-03-01), None
patent: 0 363 317 (1990-04-01), None
patent: 0 417 815 (1991-03-01), None
patent: 870019 (1961-06-01), None
patent: WO 9932692 (1999-07-01), None
“Biax Introduces the HT-Series,”[online] Biax-Fiberfilm Corporation, Greenville, WI [retrieved on Feb. 12, 2001]. Retrieved from the Internet <URL: http://www.execpc.com/~biax/products.htm>; 2 pages.
“Diagram (of Biax melt blown system), ”[online] Biax-Fiberfilm Corporation, Greenville, WI [retrieved on Feb. 12, 2001]. Retrieved from the Internet <URL: http://www.execpc.com/~biax/products.htm>; 1 page.
“Metering Pumps—Planetary Polymer Metering Pumps,”[online] Slack & Parr Ltd., Kegworth, Derby, England [retrieved on Feb. 12, 2001]. Retrieved from the Internet <URL: http://www.slackandparr.com/meter_pumps/polymer.htm>; 1 page.
Mahr GmbH, Göttingen, Germany “Feinpruef Spinning Pumps, Spin Finsih Metering Pumps and Test Stands,” Feb. 2, 2000; 12 pages.
“Planetary Melt Spinning Pumps,” Barmag SauerGroup, Sauer Inc., Charlotte, NC [retrived on Feb. 12, 2001]. Retrieved from the Internet <URL: http://www.barmag.com/e_products_planetary _pumps.htm>; 2 pages.
“Spinning Pumps,” Mahr GmbH, Göttingen, Germany [undated] 6 pages.
“Zenith® Is Your Partner For Increased Uptime, Improved Denier Uniformity, And Reduced Maintenance,” [online] Parker Hannifin Corporation, Zenith Products Division, Sanford, NC [retrieved on Feb. 12, 2001]. Retrieved from the Internet <URL: http://www.zenithpumps.com/applications/fiber.htm>; 2 pages.
“Zenith® Pumps, Planetary Gear Pumps, Installation, Care and Maintenance,” Parker Hannifin Corporation, Zenith Pumps Division, Sanford, NC, copyright 1996.
“Zenith® Pumps, Planetary Gear Pumps, Precise, Pulseless, Repeatable Performance in Hot Melt Spin Pump Application,” Parker Hannifin Corporation, Zenith Pumps Division, Sanford, NC, copyright 1998.
Breister James C.
Erickson Stanley C.
Sager Patrick J.
Schwartz Michael G.
3M Innovative Properties Company
Cleveland David R.
Hanson Karl G.
Tentoni Leo B.
LandOfFree
Meltblowing apparatus employing planetary gear metering pump does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Meltblowing apparatus employing planetary gear metering pump, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Meltblowing apparatus employing planetary gear metering pump will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3327715