Patent ID: 6261335
Filing Date: 2001-07-17
Classification: A61F,C03C

Abstract:
A biosoluble glass fiber filtration media, comprising:a fibrous filtration layer of randomly oriented, entangled flame attenuated glass fibers; the glass fibers being prepared from a glass composition consisting essentially of, in mol percent:SiO.sub.2 66-69.7 Al.sub.2 O.sub.3 0-2.2 RO 7-18 R.sub.2 O 9-20 B.sub.2 O.sub.3 0-7.1the glass composition having a C(acid) .gtoreq.1.95, a C(bio) .ltoreq.2.30, and a C(moist) k .gtoreq.2.40; the glass fibers having a biodissolution rate in excess of 150 ng/cm.sup.2 /hr; the glass fibers have a mean diameter between about 2.5.times.10.sup.-5 inches and about 11.0.times.10.sup.-5 inches; andthe fibrous filtration media having an average efficiency of 65% or greater as measured by ASHRAE 52.1 test method; the filtration layer having a thickness ranging from about 0.12 inches to about 0.35 inches; the filtration layer having a weight ranging from about 3.0 g/ft.sup.2 to about 8.0 g/ft.sup.2 ; the filtration having an initial flat sheet pressure drop of 0.35 inches of water or less; and a dirt holding capacity of about 1.5 g/ft.sup.2 or greater.