Abstract: A working chair with adjustable backrest support pre-set tension is described, in which a swiveling backrest support is positioned on a seat part, the backrest support being prestressed against the back of the user with a manually adjustable pre-set tension of an energy storing device. The front end of the energy storing device is rotatably mounted on a free, swiveling end of a guide bar close to the seat edge, and the rear end of the energy storing device is coupled to a free, swiveling end of the backrest support at a contact point which is designed to be adjustable and detectable.

Abstract: A method for production of a breathable roofing underlayment comprising a sheetlike carrier (1), for example a base nonwoven, which by a membrane (2) applied to the carrier (1) is airflow—and water—tight yet pervious to water vapour, wherein the membrane is a hotmelt adhesive film (2) applied hot directly to the carrier (1), the method comprising the steps of applying continuously to a carrier structure, for example a base nonwoven (1), a membrane (2), wherein the carrier (1) has directly applied thereto a slot-extruded film (2) of a hotmelt adhesive.

Abstract: A work or office chair having a seat shell which is pivotably arranged on a height-adjustable seat carrier, characterized by the seat shell being spring loaded to oppose tilting of the seat shell from a raised position towards a tilted, lower position. The chair includes a fixing arrangement for fixing the chair in specific tilted positions. One improvement is a spring arrangement for supporting the chair and a toggle arrangement coacting with the spring arrangement for opposing tilting of the chair with the springs of the toggle arrangement and the supporting spring coacting to require a substantial force to cause initial tilting then followed by a gradual force to cause tilting.