3m Innovative Properties Company

William T Fay

Stephen A Johnson

Timothy J Hebrink

Michael R Berrigan

Pamela A Percha

Robert M Biegler

Terence D Neavin

Anne N De Rovere

Andrew R Fox

John D Stelter

Seyed Abolhassan Angadjivand

Jo Anne Etter

Robert M Jennings

David J W Aastuen

Douglas C Sundet

Arthur L Kotz

Michael Benton Free

Kristopher J Derks

Richard Yufeng Liu

Timothy J Lindquist

Jerald W Hall, Jr

Jill R Munro

Derek W Patzman

Victor Ho

Richard J Thompson

John P Purcell

Kevin T Huseby

Troy J Anderson

John F Iii Van Derlofske

An optical film includes a plurality of polymeric layers shaped along orthogonal first and second directions. A first curve being an intersection of the optical film with a first plane orthogonal to the second direction and to a reference plane has a best-fit first circular arc subtending a first angle at a center of curvature of the first circular arc of greater than 180 degrees where the optical film has a maximum projected area in the reference plane. A second curve being an intersection of the optical film with a second plane orthogonal to the first direction and to the reference plane has a best-fit second circular arc subtending a second angle at a center of curvature of the second circular arc of at least 30 degrees. Reflectance and transmittance of the optical film are described.

Shaped optical films and methods of shaping optical films

The present disclosure relates to films having at least a first profiled layer and a second layer having an inverse profile of the first layer. Those films can be used as protection tapes for various surfaces. Exemplary uses of the films of the present disclosure include leading edge protection tapes for rotor blades.

Profiled films

Optical films having a curved shaped and methods of shaping optical films are described. A method of shaping an optical film includes the steps of disposing the optical film adjacent first and second rollers spaced apart along a first direction, securing opposing first and second ends of the optical film, providing a curved mold surface, and shaping the optical film by contacting the optical film with the curved mold surface while stretching the optical film along the first direction and keeping a threshold distance between closest points on the optical film contacting the first roller and contacting the curved mold surface less than the width of the optical film to reduce buckling of the optical film.

A feedblock including a first packet creator that forms a first packet including a first plurality of polymeric layers, the first plurality of layers including at least four first individual polymeric layers; and a second packet creator that forms a second packet including a second plurality of polymeric layers, the second plurality of layers including at least four second individual polymeric layers, wherein the first and second packet creators are configured such that, for each packet creator, respective individual polymeric layers of the plurality of polymeric layers are formed at approximately the same time. The feedblock may include a packet combiner that receives and combines the first and second primary packets to form a multilayer stream. In some examples, at least one of the first and second primary packets may be spread in the cross-web direction prior to being combined with one another.

Feedblock for manufacturing multilayer polymeric films

Apparatus for manufacturing multilayer polymeric films

A method for making a bonded nonwoven fibrous web comprising 1) providing a nonwoven fibrous web that comprises oriented semicrystalline polymeric fibers, and 2) subjecting the web to a controlled heating and quenching operation that includes a) forcefully passing through the web a fluid heated to at least the onset melting temperature of said polymeric material for a time too short to wholly melt the fibers, and b) immediately quenching the web by forcefully passing through the web a fluid at a temperature at least 50&#xb0; C. less than the Nominal Melting Point of the material of the fibers. The fibers of the treated web generally have i) an amorphous-characterized phase that exhibits repeatable softening (making the fibers softenable) and ii) a crystallite-characterized phase that reinforces the fiber structure during softening of the amorphous-characterized phase, whereby the fibers may be autogenously bonded while retaining orientation and fiber structure. Apparatus for carrying out the method can comprise 1) a conveyor for conveying a web to be treated, 2) a heater mounted adjacent a first side of the conveyor and comprising a) a chamber having a wall that faces the web, b) one or more conduits through which a heated gas can be introduced into the chamber under pressure and c) a slot in said chamber wall through which heated gas flows from the chamber onto a web on the conveyor, 3) a source of quenching gas downweb from the heater on the first side of the conveyor, the quenching gas having a temperature substantially less than that of the heated gas, 4) gas-withdrawal mean disposed on the second side of the conveyor opposite from the heater, the gas-withdrawal means having a portion in alignment with the slot so as to draw heated gas from the slot through the web and also a portion downweb from the slot in alignment with the source of quenching gas so as to draw the quenching gas through the web to quench the web. Flow restrictor means is preferably disposed on the second side of the conveyor in the path of at least one of the heated gas and the quenching gas so as to even the distribution of the gas through the web.

Bonded nonwoven fibrous webs comprising softenable oriented semicrystalline polymeric fibers and apparatus and methods for preparing such webs

A pleated filter is made from a monocomponent monolayer nonwoven web of continuous monocomponent meltspun partially crystalline and partially amorphous oriented fibers of the same polymeric composition that are bonded to form a coherent and handleable web having a Gurley Stiffness of at least 100 mg and which further may be softened while retaining orientation and fiber structure. Rows of pleats are formed in the nonwoven web, and the web is cut to a desired size and shape to provide a pleated filter element containing a self-supporting porous monocomponent monolayer matrix of fibers bonded to one another at least some points of fiber intersection and having an average initial submicron efficiency of at least 15% at a 1.52 meters/sec face velocity. The filter element is deformation resistant without requiring stiffening layers, bicomponent fibers, adhesive or other reinforcement in the filter media layer.

Pleated filter with monolayer monocomponent meltspun media

Nonwoven fibrous webs comprise fibers of uniform diameter that vary in morphology along their length. The variation provides longitudinal segments that exhibit distinctive softening characteristics during a bonding operation. Some segments soften under the conditions of the bonding operation and bond to other fibers of the web, and other segments are passive during the bonding operation. Webs as described can be formed by a method that comprises a) extruding filaments of fiber-forming material; b) directing the filaments through a processing chamber in which the filaments are subjected to longitudinal stress; c) subjecting the filaments to turbulent flow conditions after they exit the processing chamber; and d) collecting the processed filaments; the temperature of the filaments being controlled so that at least some of the filaments solidify while in the turbulent field.

Bondable, oriented, nonwoven fibrous webs and methods for making them

Nonwoven fibrous webs including amorphous polymeric fibers with improved and/or more convenient bondability are disclosed. The nonwoven fibrous webs may include only amorphous polymeric fibers or they may include additional components in addition to amorphous polymeric fibers. The amorphous polymeric fibers within the web may be autogeneously bonded or autogeneously bondable. The amorphous polymeric fibers may be characterized as varying in morphology over the length of continuous fibers so as to provide longitudinal segments that differ from one another in softening characteristics during a selected bonding operation.

Nonwoven amorphous fibrous webs and methods for making them

A new fiber-forming method, and related apparatus, and webs prepared by the new method and apparatus are taught. In the new method a) a stream of filaments is extruded from a die of known width and thickness; b) the stream of extruded filaments is directed through a processing chamber that is defined by two narrowly separated walls that are parallel to one another, parallel to said width of the die, and parallel to the longitudinal axis of the stream of extruded filaments; c) the stream of filaments passed through the processing chamber is intercepted on a collector where the filaments are collected as a nonwoven fibrous web; and d) a spacing between the walls of the processing chamber is selected that causes the stream of extruded filaments to spread before it reaches the collector and be collected as a web significantly wider in width than the die. Generally the increase in width is sufficient to be economically significant, e.g., to reduce costs of web manufacture. Such economic benefit can occur in widths that are 50, 100 or 200 or more millimeters greater in width than the width of the die. Preferably, the collected web has a width at least 50 percent greater than said width of the die. The processing chamber is preferably open to the ambient environment at its longitudinal sides to allow pressure within the processing chamber to push the stream of filaments outwardly toward the longitudinal sides of the chamber.

Method for forming spread nonwoven webs

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Woodbury, MN, United States of America

William T Fay