Polyolefin-based elastic meltblown fabrics
AssigneeExxonMobil Chemical Patents Inc.
InventorAlistair Duncan Westwood
Life of this patent
Estimating the term…
Abstract
Disclosed herein is a process for forming a multilayer construction, and the multilayer constructions including at least one layer of an elastic meltblown fabric, the process comprising extruding one or more polyolefin polymer (e.g., a propylene-α-olefin copolymer) having a MFR from less than 90 dg/min through at least one die having a plurality of nozzles to form a plurality of continuous fibers, at least one die operating at a melt pressure from greater than 500 psi (3.45 MPa) to form at least one elastic meltblown fabric, and adhering the at least one elastic meltblown fabric to at least one extensible fabric.
Claims19
A multilayer construction comprising:
- at least one layer of elastic meltblown fabric having an Ultimate Elongation of greater than 200% and consisting of:
- one or more propylene-α-olefin copolymer(s) having a comonomer-derived content within the range from 5 to 35 wt % by weight of the propylene-α-olefin copolymer and having a MFR of from 1 to 20 dg/min and a Hf value of less than 75 J/g and
- at least one extensible fabric layer having an Elongation at Peak Load in either the machine direction or the cross-machined direction or both from greater than 100%,
- wherein the layer of elastic meltblown fabric is formed by meltblowing the one or more polyolefin polymer(s), at a melt pressure of from about 750 psi to about 2000 psi, directly upon at least one of the extensible fabric layers such that the one or more polyolefin polymer(s) are still in a molten state upon contacting the at least one of the extensible fabric layers.
A multilayer construction comprising:
- an elastic meltblown fabric comprising fibers having a diameter within the range from 5 to 50 μm and consisting of one or more propylene-α-olefin copolymer(s) having a comonomer-derived content within the range from 5 to 35 wt % by weight of the propylene-α-olefin copolymer and having a MFR of from 1 to 20 dg/min and a Hf value of less than 75 J/g, wherein the propylene-α-olefin copolymer is not visbroken, and
- an extensible spunlace fabric layer having a basis weight within the range of from 10 to 150 g/m2 and an Elongation at Peak Load in either the machine direction or the cross-machined direction or both from greater than 100%,
- wherein the elastic meltblown fabric is formed by meltblowing the one or more polyolefin polymer(s), at a melt pressure of from about 750 psi to about 2000 psi, directly upon the extensible spunlace fabric layer such that the one or more polyolefin polymer(s) are still in a molten state upon contacting the extensible spunlace fabric layer;
- and
- wherein the multilayer construction has a basis weight of from 100 to 160 g/m2.
Dependencies are inferred from the claim text.