Minnesota Mining and Manufacturing Company

3m Innovative Properties Company

Daniel E Meyer

Dennis L Krueger

Thomas I Insley

Richard J Rolando

Marvin E Jones

Eugene G Joseph

Seyed A Angadjivand

Hassan Bodaghi

Leigh E Wood

William J Schultz

Michael A Johnson

Thomas P Hanschen

Wendy L Thompson

Ryan E Marx

James F Dyrud

David L Braun

David A Olson

Jay M Jennen

John F Reed

John E Riedel

Stanley C Erickson

Peter O Rekow

Scott M Purrington

Cynthia Y Tamaki

Donald E Young

Paul R Suszko

Karen J Calverley

Paul S Engelen

Thomas L Insley

Philip A Anderson

Ronald R Gorke

Multilayer polymeric films which may be useful for protecting the leading edges of aircraft from rain and sand erosion are presented. Typical surface protection films comprising two or more layers of a first material alternating with one or more layers of a second material, wherein the first and second materials are different materials, wherein the first and second materials comprise first and second polymers, wherein the first and second materials have a first and second Shore hardness, and wherein the first Shore hardness is greater than the second Shore hardness by more than 5 A or more typically more than 10 A.

Multilayer erosion resistant protective films

A thermoforming method and objects prepared using the thermoforming method are described. Non-self-supporting, polymeric films are initially formed into a three-dimensional shaped film on a male mold and then transferred to a female mold while being supported by the male mold. The three-dimensional shaped film can be further thermoformed, reinforced, or a combination thereof on the female mold. The resulting object has a substantially uniform thickness across a major surface. The method can preserve the surface quality of the polymeric film used to prepare the three-dimensional objects.

Methods of thermoforming non-self-supporting polymeric films and articles made therefrom

Electret filter media comprising a nonwoven web of thermoplastic nonconductive microfibers having trapped charge, said charge provided by (1) subjecting the nonwoven web to a corona treatment, followed by (2) impingement of jets of water or a stream of water droplets on the web at a pressure sufficient to provide the web with filtration enhancing electret charge and (3) drying the web. This electret filter media may be used in a respiratory mask to provide extraordinarily good filtration properties.

Electret filter media and filtering masks that contain electret filter media

An electret filter media, and mask, that is made of a nonwoven web of thermoplastic microfibers. The thermoplastic microfibers are of substantially the same composition, are nonconductive, and have an effective fiber diameter less than about 15 micrometers. The nonwoven web also has sufficient unpolarized trapped charge to exhibit an initial filtration quality factor of at least 0.31 when measured under the DOP Penetration and Pressure Drop Test.

Electret filter media

Oriented microfibers and processes for making them are disclosed, together with blends of such microfibers with other fibers such as crimped staple fibers and non-oriented microfibers.

Oriented melt-blown fibers, processes for making such fibers and webs

A method of making a microfibrous sorbent article is provided. The method includes the steps of a) extruding molten thermoplastic fiber forming polymer from multiple orifices in a fiber-forming die, said orifices being aligned along the face of the die; b) attenuating the fibers in a stream of hot air to form a fiber stream of microfibers; and c) collecting said microfibers on a collector having a forming surface, said surface being aligned with said die and substantially parallel to and equidistant from said die such that the fibers form a spirally wound microfibrous sorbent article which is supported on its exterior surface by said forming surface and which is drawn across said forming surface substantially parallel to said die. Also provided is a microfibrous sorbent article prepared according to the method.

Method of making sorbent articles

A method of charging a nonwoven web of thermoplastic microfibers to provide electret filter media is provided. The method includes impinging on a nonwoven web of thermoplastic nonconductive microfibers capable of having a high quantity of trapped charge jets of water or a stream of water droplets at a pressure sufficient to provide the web with filtration enhancing electret charge and drying said web.

Method of charging electret filter media

A microfibrous sorbent article is provided. The microfibrous sorbent article comprises an elongate boom having a substantially oval cross-section. The boom is formed of multiple adjacent microfibers layers, the layers being bonded to each other by entanglement of fibers between adjacent layers. Also provided is a method for making the microfibrous sorbent article.

Sorbent articles

Irradiated polypropylene articles of non-crystalline mesomorphous polypropylene and a method for preparing the articles are provided. The articles are irradiated with a sterilizing dosage of ionizing radiation. The irradiated articles such as films and blown microfiber webs are substantially undegraded after storage periods of as long as six months.

Radiation resistant polypropylene articles and method for preparing same

A highly conformable and deformable nonwoven web comprising melt-blown microfibers having multiple layers of a relatively low modulus material and a high modulus material.

Stretchable nonwoven webs based on multi-layer blown microfibers

A nonwoven elastomeric web is provided. The web comprises thermoplastic elastomeric melt-blown small diameter fibers having a diameter of less than about 50 microns, the small diameter fibers being randomly arrayed and bonded at points of contact such that the tensile strength of the web in the direction of web formation is no greater than about 2.5 times the tensile strength of the web in a direction perpendicular to the direction of web formation and the web recovers at least about 85% in the machine direction after being stretched 50%. The web is particularly useful as wound dressing or bandaging materials.

Elastomeric adhesive and cohesive materials

A method for forming melt-blown fiber webs which webs have multiple layers of polymeric material. The method provides novel webs and control over web properties.

Method of forming a web of melt blown layered fibers

A high modulus nonwoven web is produced using a high modulus material and a self-bonding material formed as multi-layer melt-blown microfibers where the web modulus is greater the MX.sub.1 +MX.sub.2 where M.sub.1 and M.sub.2 represent the modulus values of webs formed from the two materials and X.sub.1 and X.sub.2 represent the respective volume portions of the materials in the web fibers.

Modulus nonwoven webs based on multi-layer blown microfibers

A method for preparing melt-blown microfibers comprising extruding fiber-forming material through the orifices of a die into a high-velocity gaseous stream where the extruded material is rapidly attenuated into fibers, directing the attenuated fibers into a first open end of a tubular chamber disposed near the die and extending in a direction parallel to the path of the attenuated fibers as they leave the die, introducing air into the tubular chamber at a velocity sufficient to maintain the fibers under tension during travel through the chamber, and collecting the fibers after they leave the tubular chamber.

Process for making oriented melt-blown microfibers

Polypropylene articles are provided. The polypropylene articles include non-crystalline mesomorphous polypropylene having olefinic unsaturation-containing monomers graft-polymerized thereon by ionizing radiation in a dosage sufficient to degrade crystalline polypropylene. The irradiated polypropylene articles retain useful tensile properties after storage periods of as long as at least about four months. Further provided is a method for preparing irradiation polypropylene articles having olefinic unsaturation-containing monomers graft-polymerized thereon including the steps of melt extruding polypropylene; quenching the extruded polypropylene immediately after extrusion to provide non-crystalline mesomorphous polypropylene; coating the non-crystalline mesomorphous polypropylene with an ionizing radiation graft-polymerizable monomer; and irradiating the coated non-crystalline mesomorphous polypropylene with a dosage of ionizing radiation sufficient to degrade crystalline polypropylene and sufficient to effect graft-polymerization of the monomer onto the surface of the polypropylene.

Growing community of inventors

Stillwater, MN, United States of America

Daniel E Meyer