摘要 |
Plastics material mesh structures are made by providing a starting material having a pattern of primary holes or depressions and smaller secondary holes or depressions between the primary holes or depressions and stretching the plastics material to orientate the zones between adjacent holes or depressions to form orientated strands. A first stretch in a single direction produces intermediate structures having first mesh openings and smaller second mesh openings. A subsequent stretch at right angles to the first stretch produces structures having main orientated strands interconnected by shorter orientated strands arranged in such a way that only three strands meet at any junction.
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