Patent ID: 7125460

Claim:
A method of forming a bi-layered, fire resistant (“FR”) nonwoven fiber batt, comprising: forming a first nonwoven fiber batt from a first fiber blend consisting of charring fibers polyester carrier fibers and polyester binder fibers; forming a second nonwoven fiber batt from a second fiber blend consisting of oxygen-depleting fibers polyester carrier fibers and polyester binder fibers; disposing said first and second nonwoven fiber batts relative to onc another such that said second nonwoven fiber batt forms an inner layer of said bi-layered FR nonwoven fiber batt and said first nonwoven fiber batt forms an outer layer of said bi-layered FR nonwoven fiber batt; wherein, upon application of flame andlor heat to said bi-layered FR nonwoven fiber batt, said inner layer of said bi-layered FR nonwoven fiber batt generates oxygen depleting gases while said outer layer of said bi-layered FR nonwoven fiber batt chars but maintains sufficient structural integrity to trap said oxygen depleting gases, generated by said inner layer of said bi-layer FR nanwoven fiber batt, between said inner and outer layers of said bi-layered FR nonwoven fiber ban.