摘要 |
<p>The layer of basic material (16) is covered by a foam, especially latex foam (31), covering layer (17). Air-tight hollows are located between the basic and covering layers, and are formed by air-tight hollow bodies (23) which preferably extend over only part of the depth of the covering layer. At least parts of the outer surfaces of the hollow bodies are concave and or convex. The covering layer and then a support layer are applied in pourable or spreadable form onto the air tight hollow bodies placed on the base layer.</p> |