Patent ID: 9498932
Filing Date: 2016-11-22
CPC Classification: B32B,D01D,D01F,D04H,Y10T

Claim Text:
1. A method for forming a multilayer meltblown composite, consisting of: meltblowing a first material to form a first meltblown layer, wherein the first material comprises one or more resins having an Ultimate Elongation (UE) of from about 50% to about 250%; meltblowing a second material to form a second meltblown layer, wherein the second material comprises one or more resins having an Ultimate Elongation (UE) of 200% or more; and meltblowing a third material to form a third meltblown layer, wherein the third material comprises one or more resins having an Ultimate Elongation (UE) of from about 50% to about 250%; wherein each resin has a MFR of about 2,000 dg/min or less, as measured by ASTM D1238, 2.16 kg, 230° C., and at least one of the first, second, and third materials comprises a propylene-α-olefin copolymer having a heat of fusion of 75 J/g or less and having a recovery of at least 70% after 100% deformation, as measured by ASTM D412, wherein the first, second, and third meltblown layers are formed in situ such that the layers form an in situ laminate; wherein the first and the third meltblown layers are facing layers; and wherein at least one of the facing layers consists of (a) polypropylene, wherein the polypropylene has a heat of fusion ranging from 60 J/g to 189 J/g, and (b) about 0.5 wt % of a blend component, wherein the blend component is selected from the group consisting of impact copolymers, random copolymers, polyethylenes, polyethylenes with a weight average molecular weight of less than 20,000 g/mol, polypropylenes having a weight average molecular weight of less than 20,000 g/mol, polyalphaolefins, and combinations thereof.