Patent CH-691319-A5 (CH)
Title: Shaped hard foam component for construction insulation etc has compressed zone(s) at the outer surface from the inner core material shaped by heat and pressure without affecting the cellular structure of the core
Inventor: VOGT JUERG
IPC: E04D13/16
Filed: 1996-07-10
Abstract: The shaped body (4), of a hard foam material, has at least one outer zone surface with a higher compression than the core zone. The transit is continuous between the core zone and the compressed zone(s). The core and the compressed zones are formed from a single component workpiece.  The compressed zones all have the same or different levels of compression. At least one compressed zone has an embedded reinforcement, with a mechanical and/or chemical anchor. At least one compressed zone is bonded to a flexible or rigid layer. Sections of the surface are profiled. At least one compressed zone is permeable to steam. The core material has a specific gravity which is equal to the specific gravity of the original component workpiece material, and especially 10-100 kg/m<3> and preferably 20-50 kg/m<3>. A significant portion of the compressed zone(s) has a layer thickness of 0.5-5.0 mm and preferably 1-4 mm and especially 1.5-2.5 mm. The shaped component (4) is a gutter or a half-shell or a board, especially with a quadrilateral or rectangular base contour, with the compressed zones at the upper surface. At least one end surface can be profiled. The reinforcement is a woven, knitted or nonwoven material, a band of filaments, a ribbon, grid, netting, or combinations of them. They are especially of plastics and/or glass and/or natural fibers and/or metals. Their surfaces have an adhesive and/or a coating. The bond between the compressed zone(s) and the flexible layer is by lamination, such as to a roof lining, vapor barrier or block, or lamination to a rigid layer such as a plasterboard, cement-bonded chipboard, silicate fiberboard, etc. The shaped profile is a groove, step fold or a combination of a groove and comb together with profile combinations. The steam permeability is through perforations in the compressed zone(s). An Independent claim is included for a shaped body production process, where the thermoplastic hard foam workpiece in the required shape and dimensions is subjected to heat and pressure to give a compression to one or more zones. The blank is cooled, and further compressed into the required dimensions for the final product, and retained until the material of the component (4) has achieved the required natural stability. During the compression and cooling stages, the cell structure is maintained in the core zone. The shaped component is bonded to a flexible or a rigid layer. Preferred Features: The workpiece is fitted with a surface reinforcement before compression by heat and pressure. The compression and cooling stages are continuous, in a double-belt heating/cooling press, where the cooling stage follows the heating stage. The original workpiece component, of expanded polystyrene with a specific gravity of 30 kg/m<3>, is subjected to a pressure of 1 bar and a temperature of 20-50  deg C. In the second stage, the pressure/heat are maintained for 15-60 secs.