Ahlstrom Glassfibre Oy

Kay R&ouml;kman

Juhani Jansson

Eino Laine

Hanna Rahiala

Harri Kostamo

Andrea Grosso

Jonathan George

Juha Bohm

A non-woven mat useful for a wide variety of purposes, including forming reinforced resin products, is produced in a manner having different specific uses of, and advantages over, conventional chopped strand mats and conventional glass tissue. The mat is preferably made by the foam process (but may be made by the liquid process), and at speeds well in excess of 60 m./min., and has a substantially uniform construction even when low density (e.g. 100 g/m or less). At least 20% (preferably at least 85%) of the fibers are in fiber bundles with between 5-450 fibers/bundle. The fibers (typically at least 85%) have a length between 5-100 mm, preferably 7-50 mm, substantially the same as the length of the fiber bundle they are in. The fibers are preferably held in the bundles by substantially non-water soluble sizing, such as epoxy resin or PVOH. The fibers in the bundles typically have diameters of approximately 7-500 microns, preferably about 7-35 microns. The bundles may comprise at least 10% reinforcing fibers, such as glass, aramid or acrylic.

Chopped strand non-woven mat production

Disclosed is a method of producing a non-woven web of fibrous or particulate material comprising: formation of a foam slurry; deposition of that slurry onto a foraminous element having a three-dimensional mold; and formation of a web having a three-dimensional shape that is not substantially planar by removal of foam from the slurry through the foraminous element and drying the web. An apparatus therefor is also disclosed. The method may be used in production a variety of products, including automotive pleated fluid and air filters, pleated heating and/or air conditioning (HVAC) filters, shaped breathing mask filters and bacterial filters, laminated cleaning products with super-absorbent middle layers, such as a mop wipe shape to fit a cleaning mop head, and other products.

Method for foam casting using three-dimensional molds

A nonwoven web of fibrous material is made by the foam process using a manifold of a particular construction. The manifold has a casing with first and second opposite ends including an inlet for a foam-fiber-surfactant slurry at the first end, and optionally a valved outlet at the second end. A center section of the manifold casing has a (e.g. rectangular) cross-section that becomes smaller moving from an inlet toward the outlet. First and second substantially closed side walls, a porous front wall having an effective length, and a back wall opposite the front wall, are provided for the center section, the walls planar or curved. Any suitable structures are provided for introducing a second (e.g. substantially fiber-free, or a fiber-foam slurry) foam into the center section through the back wall. Pressure sensors penetrating one or both of the side walls may sense the pressure within the center section, and automatically control the introduction of slurry into the inlet, withdrawal through the outlet, and/or introduction of the second foam into/through the back wall, so as to maintain the basis weight of the foam-fiber slurry passing through the front wall substantially constant along the effective length of the front wall.

Foam process web production with foam dilution

Growing community of inventors

Karhula, Finland

Kay Rökman

Growing community of inventors

Karhula, Finland

Kay R&ouml;kman

Kay Rökman