US Patent 7892631 Lightweight board and process for its production

The invention pertains to a lightweight board with two thin-walled top layers and at least one core layer located between the top layers and connected to these, and a process to manufacture this. The process to manufacture the invented lightweight board is characterised by a first process stage in which a groove is made in at least one longitudinal side of the lightweight board, a profile strip is inserted in a second process stage into the groove in the lightweight board and a further profile strip is attached in a third stage on the previously attached profile strip. The process to manufacture another invented lightweight board is characterised by a first process stage in which a groove is made in at least one longitudinal side of the lightweight board, a profile strip is inserted in a second process stage into the groove in the lightweight board, the profile strip projecting over the groove in the lightweight board is removed in a third process stage and a further profile strip is attached to the previously trimmed profile strip in a fourth process stage.