Abstract: A biosoluble glass fiber filtration media includes a fibrous filtration layer of randomly oriented, entangled glass fibers which has an initial efficiency of 25% or greater as measured by ASHRAE 52.1 test method. The glass fibers forming the media have a biodissolution rate in excess of 150 ng/cm2/hr and a mean diameter between about 2.5×10−5 inches and about 11.0×10−5 inches. Typically, the filtration layer has a thickness ranging from about 0.12 inches to about 0.35 inches and a density ranging from about 3.0 g/ft2 to about 8.0 g/ft2. The filtration has an initial pressure drop of about 0.35 inches of water or less and a dirt holding capacity of about 1.5 g/ft2 or greater.

Abstract: Relatively viscous glass is fiberized in a rotary fiberization process at relatively high disk speeds and through relatively large diameter holes to form long, fine diameter glass fibers which preferably are rapidly solubilized in biological fluids. The method of forming the long, fine diameter glass fibers includes maintaining a ratio of the velocity of the external surface of the peripheral wall of the fiberizing disk to the velocity of the glass passing through the fiberizing orifices within a specific range (the disc/glass velocity ratio); maintaining a ratio of the velocity of the air exiting the air ring to the velocity of the glass passing through the fiberizing orifices within a specific range (the air-ring/glass velocity ratio); and maintaining a ratio of the BTU content of the fuel expended forming the hot attenuating combustion gases to the BTU content of a pound of molten glass being fiberized within a specific range (the attenuating combustion gases/glass heat content ratio).

Abstract: Resilient battery separator media, especially adapted for use as battery separators for starved electrolyte batteries, are formed from air laid, fibrous mats of randomly oriented, entangled microfibers which may be needled to further entangle the fibers. The fibrous mats may be essentially uniform in density throughout their thickness or may include one or two relatively high density, high tensile strength fibrous surface layer(s) and a relatively low density, more resilient fibrous layer integral with and, in one embodiment, intermediate the two surface layers wherein the fibers in the surface layer(s) of the mats are more entangled than the fibers in the resilient layer. The fibrous mats, with one or two surface layers, are formed from the air laid fibrous mats by further entangling the fibers at and adjacent one or both surfaces of the mats, e.g. through hydroentanglement, relative to the entanglement of the fibers in the resilient fibrous layer.

Abstract: A resilient battery separator, especially suited for use in a starved electrolyte battery, is made of an air laid fibrous mat of randomly oriented, entangled microfibers having a mean diameter between 0.5 and 2.0 microns. The air laid mat weighs between 50 and 450 g/m.sup.2 and has a thickness between 0.01 and 0.5 inches. The fibrous mat may be essentially uniform in density throughout its thickness or may include one or two relatively high density, high tensile strength fibrous surface layer(s) and a relatively low density, more resilient fibrous layer integral with and, in one embodiment, intermediate the two surface layers. The microfibers in the surface layer(s) are more entangled than the microfibers in the resilient layer. In a starved electrolyte battery, the separator has a thickness, when subjected to a loading of 1.5 psi, that is equal to or greater than the spacing between the electrode plates of the battery and, preferably, at least 110% of the spacing between the electrode plates of the battery.

Abstract: A composite filter media includes a fibrous filtration layer of randomly oriented fibers and one or more pleatable stiffening layers which enable the composite filter media to be pleated and hold or retain its pleats. The pleatable stiffening layer(s) may enhance the dirt holding capacity of the composite filter media especially when positioned upstream of the fibrous filtration layer. The composite filter media may also include a flexible covering layer which functions to block the loss of fibers from the fibrous filtration layer. Preferably, the mean fiber diameter of the fibers in fibrous filtration layer increases and the density of the fibrous filtration layer decreases throughout the thickness of the fibrous filtration layer from one major surface to the other major surface of the fibrous filtration layer.

Abstract: A flame attenuation apparatus for forming flame attenuated fibers, preferably glass fibers, includes means for providing continuous filaments; burner means for providing a high temperature, high energy stream of combustion gases; means for feeding the continuous filaments into the high temperature, high energy stream of combustion gases; and an elongated rod filament guide with a plurality of grooves therein for receiving, guiding and supporting the continuous filaments, as the continuous filaments are fed into the high temperature, high energy stream of combustion gases. The elongated rod is preferably made from graphite with a boron-nitride coating and, preferably, has at least two flat surfaces and at least two curved surfaces with the grooves therein.

Abstract: A composite filter media includes a fibrous filtration layer of randomly oriented fibers and one or more pleatable stiffening layers which enable the composite filter media to be pleated and hold or retain its pleats. The pleatable stiffening layer(s) may enhance the dirt holding capacity of the composite filter media especially when positioned upstream of the fibrous filtration layer. The composite filter media may also include a flexible covering layer which functions to block the loss of fibers from the fibrous filtration layer. Preferably, the mean fiber diameter of the fibers in fibrous filtration layer increases and the density of the fibrous filtration layer decreases throughout the thickness of the fibrous filtration layer from one major surface to the other major surface of the fibrous filtration layer.

Abstract: A composite filter media includes a fibrous filtration layer of randomly oriented fibers and one or more pleatable stiffening layers which enable the composite filter media to be pleated and hold or retain its pleats. The pleatable stiffening layer(s) may enhance the dirt holding capacity of the composite filter media especially when positioned upstream of the fibrous filtration layer. The composite filter media may also include a flexible covering layer which functions to block the loss of fibers from the fibrous filtration layer. Preferably, the mean fiber diameter of the fibers in fibrous filtration layer increases and the density of the fibrous filtration layer decreases throughout the thickness of the fibrous filtration layer from one major surface to the other major surface of the fibrous filtration layer.

Abstract: A composite filter media for bag or pocket filters and the like includes an upstream dirt-holding layer of fine polymeric fibers and a downstream high efficiency filtration layer of glass fibers. The upstream layer includes polymeric microfibers having a mean fiber diameter ranging from about 2.5 to about 4.5 microns, lofting fibers and binder fibers; and weighs between about 2.0 and about 7.0 grams per square foot. The glass fiber layer has a weight between about 1.2 and about 2.7 grams per square foot; the average diameter of the fibers in the glass fiber layer is within a range from 3.0.times.10.sup.-5 to 4.1.times.10.sup.-5 inches; and the fibers are bonded together at their points of intersection with a binder. The composite filter media has an average air filtration efficiency of at least 80%.

Abstract: An air filtration media is formed of a blanket of fibers, preferably glass fibers, bonded together at their points of intersection with a binder. The blanket has a weight between about 2.5 and about 4.0 grams per square foot and the average diameter of the fibers in the blanket is within a range from 3.0 .times.10.sup.-5 to 4.1.times.10.sup.-5 inches. The blanket has an average air filtration efficiency of at least 80% and the pressure drop across the thickness of the blanket is no greater than 0.30 inches of water. The blanket can be used alone; with a permeable backing sheet; or with a second layer or blanket of filtration media, as part of a dual-phase or multi-phase air filtration media.