Flexible and permeable sheet

A process for preparing a sheet material having an upper surface and a lower surface comprising a net of fibers having plastic beaded bodies integrally molded therein such that the upper surface of the material has discrete elevated portions and the lower surface of the material is flat,

• which process comprises:
• placing a net of fibers in a mold comprising an upper section having a main feed hole located therein and a flat bottom, a middle section having on its top surface a plurality of feed holes connected one to another by channels and having on its bottom surface a plurality of hemispherical indentations, and a lower section which is flat, wherein the net of fibers is placed between the middle and lower sections;
• closing the mold;
• injecting a plastic material under pressure through the main feed hole such that the plastic material passes through the feed holes and channels of the middle section to the indentations on its bottom surface, whereby the plastic material infiltrates the net of fibers and forms integrally molded plastic bead bodies on the upper surface of the net of fibers;
• and
• releasing the sheet material from the mold.