to 1 atm abs the following operations have been the same as in example 1 the produced carboard has had the following physical and mechanical properties mass per 1 m 2 170 g breaking length 2150 m density 0 50 g cm 3 for manufacturing wrapping paper the fibrous suspension of brown wood pulp with a fibre concentration of 18 and a freeness of 65 u00b0 according to schopper riegler has been heated by steam at 130 u00b0 c under a pressure of 2 8 atm abs to the state of equilibrium of moisture content between the fibrous suspension and steam in the closed volume of the heating chamber the heated fibrous suspension has been delivered in a stream of air and steam into a moulding chamber and the steam pressure has been sharply reduced from 2 8 atm abs to 1 atm abs the following operations have been the same as in example 1 the physical and mechanical properties of the produced wrapping paper have been as follows mass per 1 m 2 70 g breaking length 3000 m density 0 48 g cm 3 for manufacturing cardboard the fibrous suspension of bleached sulphite cellulose with a fibre concentration of 30 and a freeness of 90 u00b0 according to schopper riegler has been heated by steam at 142 u00b0 c under a pressure of 4 atm abs to the state of equilibrium of moisture content between the fibrous suspension and steam in the closed.