Hercules Corporation

Richard J Legare

Rakesh K Gupta

Randall E Kozulla

Robert G MacLellan

James D Geiman

James H Harrington

Shiv Sibal

Walter J Freeman

James H Godsey

Robert F Keller

William Robert Lanigan

James L Jacox

Adrienne W Williams

Thomas L Smith

A method of forming a thermally bonded, nonwoven polypropylene fabric is provided and includes passing a web of thermally bondable skin-core polypropylene fibers through a calender nip under heat and pressure to produce a nonwoven fabric having elongation. The patterned calender roll is embossed with a plurality of spaced and staggered lands particularly dimensioned, configured and oriented to provide the desired bonding spot size and spacing between the bonding spots such that when utilized in the calender roll, an improved soft polypropylene fabric or cover sheet having a high elongation results.

Method and apparatus for thermal bonding high elongation nonwoven fabric

A yarn comprising linear low density polyethylene fiber and nonmelting fiber or fiber having a melting point higher than the linear low density polyethylene fiber, and structures made therefrom.

Yarns containing linear low density polyethylene fibers

A laminate comprising (1) at least one layer of a textile structure comprising linear low density polyethylene fiber and (2) at least one layer of a textile structure comprising nomnelting fiber or fiber having a melting point higher than the linear low density polyethylene fiber, needlepunched and thermally consolidated together.

Laminates comprising textile structures comprising linear low density

A fabric comprising a warp yarn and a filling yarn, wherein the filling yarn comprises linear low density polyethylene fiber and the warp yarn comprises nonmelting fiber or fiber having a melting point higher than the linear low density polyethylene fiber.

Fabrics comprising filling yarns comprising linear low density

A fiber comprising at least about 80% by weight linear low density polyethylene and having a melting point &gt;109.degree. C. is disclosed. Also disclosed are thermally consolidated fiber structures comprising (1) at least about 3% by weight, based on the total weight of the structure, of lower melting binder fibers comprising at least 80% by weight linear low density polyethylene, and (2) not more than 97% by weight, based on the total weight of the structure, of nonmelting fibers, or fibers having a melting point higher than the linear low density polyethylene fibers. The fiber structures can be in the form of multifilament yarns, woven or nonwoven textile fabrics, carpets, or laminates. The linear low density polyethylene binder fibers in the structures preferably have a melting point &lt;109.degree. C.

Textile structures containing linear low density polyethylene binder

Protective articles such as diapers, having filmless hydrophobic barrier elements such as cuffs and backing sheets. The barrier cuffs--which can be, for instance, leg cuffs and waistbands--and the backing sheets can be provided from fabrics having a fabric weight of at least 10 gsy; these fabrics are made of cardable, hydrophobic polyolefin fibers having a dpf value of not more than about 2.0.

Barrier element fabrics, barrier elements, and protective articles

A gamma-sterilizable barrier fabric comprises (1) at least one layer of a gamma-sterilizable nonwoven material comprising cardable multiconstituent staple fibers, at least 50% by weight of the nonwoven material comprising a gamma-sterilizable polymer, and (2) at least one layer of gamma-sterilizable barrier material selected from film, wet-laid fabrics, and melt-blown webs, at least 50% by weight of the barrier material comprising a gamma-sterilizable polymer.

Gamma-sterilizable barrier fabrics

Nonwoven structures, prepared from meltblown microfibers, and fibers having heterogeneous melt viscosity. The structures can be in the form of composite nonwoven fabrics, made from alternating layers of the indicated meltblown and heterogeneous fibers; the melt flow rate, of the surface of the heterogeneous fibers, can be one third or more of the meltblown fibers' melt flow rate. The composite nonwoven fabrics have excellent barrier properties, and are useful as sterilization wraps, and for other medical, industrial, and hygiene applications.

Textile structures, and their preparation

The fabrics of this invention have a unique combination of liquid barrier properties and high air permeability and comprise at least one carded nonwoven web comprising at least 10% by weight, based on the total weight of cardable fibers, of cardable polyolefin fibers having a fiber fineness of about 0.5 to about 1.2 decitex. Preferably the polyolefin fibers are hydrophobic polyolefin fibers, and the nonwoven material is thermally bonded. Laminates comprising at least one layer of the fabrics of this invention and at least one layer of another nonwoven material have the same unique combination of properties.

Nonwoven materials comprising 0.5 to 1.2 decitex cardable polyolefin

An improved crosslinked double base propellant composition is provided which has an improved binder system. The binder system is based on nitrocellulose (NC) having an intrinsic viscosity of from about 0.4 dl./gram to about 1.5 dl./gram and a polyester polyol or polyether polyol (polyol), in which the weight ratio of NC/polyol is from about 0.03/1 to about 0.8/1. The binder crosslinking agents are diisocyanates, and the ratio of NCO groups of the diisocyanates to combined OH groups of nitrocellulose and polyol is from about 0.7/1 to 1.2/1. Energetic plasticizer such as nitroglycerin comprises from about 68% to about 82% by weight of the binder. The binder contains a stabilizer and is capable of high solids loading, i.e., 70% to 77% solids.

Growing community of inventors

Conyers, GA, United States of America

Richard J Legare