Abstract: A manufacturing method of a sound insulating layer by application of raw materials for urethane resin, by applying row materials for urethane resin in their liquid states along a surface of a porous layer of a soundproof body to manufacture as the sound insulating layer.

Abstract: The invention relates to a method for producing a polyurethane foam, wherein a mixture having the following is discharged from a mixing head through a discharge line: A) a component reactive toward isocyanates; B) a surfactant component; C) a blowing agent component selected from the group comprising linear, branched, or cyclic C1 to C6 hydrocarbons, linear, branched, or cyclic C1 to C6 fluorocarbons, N2, O2, argon, and/or CO2, wherein the blowing agent C) is present in the supercritical or near-critical state; and D) a polyisocyanate component. The component A) has a hydroxyl value=100 mg KOH/g and =1000 mg KOH/g. The blowing agent component C) is present at least partially in the form of an emulsion, and means provided with an opening or several openings are arranged in the discharge line in order to increase the flow resistance during the discharge of the mixture comprising A), B), C), and D), wherein the cross-sectional area of the opening or the sum of the cross-sectional areas of all openings is =0.