Low density microfiber nonwoven fabric
AssigneeKimberly-Clark Worldwide, Inc.
InventorsLawrence Howell Sawyer, Linda Ann Connor, Samuel Edward Marmon
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Abstract
The present invention provides a lofty nonwoven web containing pneumatically drawn filaments, wherein the web has a density from about 0.01 g/cc to about 0.075 g/cc and the microfilaments have a weight-per-unit length between about 0.1 dtex and about 1.5 dtex. The invention also provides a process for producing the lofty nonwoven web.
Claims13
A lofty nonwoven web comprising spunbond microfilaments, wherein said lofty web has a density from about 0.01 g/cc to about 0.075 g/cc and said microfilaments have a weight-per-unit length between about 0.66 dtex and about 1.0 dtex.
A nonwoven web comprising multicomponent spunbond conjugate microfilaments comprising an ethylene polymer having a melt flow rate between about 60 g/10 min. and about 250 g/10 min. and a propylene polymer having a melt flow rate between about 50 g/10 min. and about 250 g/10 min. wherein said lofty web has a density from about 0.01 g/cc to about 0.075 g/cc and said microfilaments have a weight-per-unit length between about 0.1 dtex and about 1.0 dtex.
A lofty nonwoven web comprising spunbond microfilaments, wherein said web is made by a process which comprises:
- melt spinning continuous multicomponent conjugate filaments comprising a high melt flow rate ethylene polymer and a high melt flow rate propylene polymer, said ethylene polymer and propylene polymer being arranged to occupy distinct zones across the cross-section along the length of said conjugate filaments, said ethylene polymer occupying at least a portion of the peripheral surface along the length of said conjugate filaments, wherein said ethylene polymer is a homopolymer or copolymer of ethylene and has a melt flow rate between about 60 g/10 min. and about 400 g/10 min., as measured in accordance with ASTM D1238-90b, Test Condition 190/2.16, and said propylene polymer is a homopolymer or copolymer of propylene and has a melt flow rate between about 50 g/10 min. and about 800 g/10 min., as measured in accordance with ASTM D1238-90b, Test Condition 230/2.16;
- quenching the spun conjugate filaments so that the conjugate filaments have latent crimpability;
- drawing the spun conjugate filaments to form microfilaments;
- activating said latent crimpability so that the conjugate filaments attain crimps;
- and
- depositing the crimped filaments to form a nonwoven web,
- wherein said lofty web has a density from about 0.01 g/cc to about 0.075 g/cc and said microfilaments have a weight-per-unit-length between about 0.1 dtex and about 1.5 dtex.
Dependencies are inferred from the claim text.