Abstract: A dispenser for compressible fiberglass nonwoven pads including a bag into which a stack of fiberglass pads is placed. A significant portion of the air within the bag is removed, compressing the stack of filter pads to reduce space. At least two flanges are formed on two adjoining edges of the bag. The flanges can be cut along a portion of their length to form an aperture through which the filter pads can be removed, while retaining the filter pads until deliberate removal by hand.

Abstract: A filter medium, a tackified binder composition and a method for providing a uniformly distributed tackifier on the glass fibers of an unwoven fiberglass web for improving filtration capacity and efficiency. An emulsified tackifier, such as polybutene, is mixed with a conventional binder composition and applied to the fibers before they are expanded into the web. The binder is cured in the conventional manner and the tackifier migrates to the surface on each fiber to enhance particle adsorption.

Abstract: A filter medium, a tackified binder composition and a method for providing a uniformly distributed tackifier on the glass fibers of an unwoven fiberglass web for improving filtration capacity and efficiency. An emulsified tackifier, such as polybutene, is mixed with a conventional binder composition and applied to the fibers before they are expanded into the web. The binder is cured in the conventional manner and the tackifier migrates to the surface on each fiber to enhance particle adsorption.

Abstract: A nestable filter having a central panel with a frame attached around the peripheral edges of the central panel. The central panel has elongated corrugations which extend longitudinally from one side to the opposite side. The frame is made up of frame members which have a generally V-shaped cross-section, the inner leg of which attaches to the edges of the corrugated central panel. Corrugated voids are formed on the inner wall of at least two of the frame members, aligned with the channels formed by the corrugations, permitting the filter to nest within a similarly constructed filter.

Abstract: A filter having a nestable frame including a first leg, a second leg extending obtusely from the first leg, and a third leg extending from the second leg and forming a channel between the second and third legs. A brace having similar first, second and third legs is mounted to the frame, with the second and third legs of the brace preferably extending into the channel of the frame. A chamber is formed by the second and third legs of the frame and the second and third legs of the brace. The chamber is preferably filled with material which rigidities the box beam structure formed by the walls surrounding the chamber. A filter medium material attaches to the frame, by adhesion and/or by clamping engagement between the first legs of the frame and brace.