Abstract: A starting material is provided having a rectangular grid of holes and the starting material is stretched in the MD to such an extent that the junctions are not significantly oriented, is stretched in the TD to such an extent that the junctions are not significantly oriented, and is finally stretched in the MD to such an extent that the junction centres thin down by at least 30% and there is significant narrowing down of the junction The resultant MD stretch is substantially greater than the resultant TD stretch. The MD strands, having thinned down and oriented to a substantial degree, cause the orientation to pass into the ends of the junctions and right through the junctions. The junctions increase in length by a ratio of at least about 2.5:1 and narrow down substantially. The ends of the junctions are not stretched more than 100% more than the centres.

Abstract: A starting material is stretched longitudinally to produce a geogrid. The starting material has pronounced ribs on each face, merging into sloping sides. Between the ribs, there are holes on a square grid. The mean thickness of the longitudinal elements is substantially greater than the mean thickness of the interconnecting elements, and the cross-sectional area of the longitudinal elements is at least 2.5 times the transverse cross-sectional area of the interconnecting elements. The longitudinal elements are stretched out into continuous oriented strands. The centers of the junctions reduce in thickness by at least 10% but substantially less than the percentage reduction at the thinnest part of the strand.

Abstract: To form a paved surface, a laminate is used which has on the bottom a geotextile fabric with the mesh structure on the top. The fabric is adhered to the road base by spraying or spreading a bituminous liquid onto the base and laying on the laminate and applying further adhesive to the top of the laminate; asphalt is then placed and rolled. The laminate is formed of a square or rectangular mesh structure which has oriented stands connected at junctions which are thicker than the strands and have low-orientated or unorientated nodules. On one side the surface of the nodules are melted and the fabric is pressed into the nodules so that the plastics material of the nodules envelopes some of the fibres or filaments of the fabric to form a mechanical bond. In this way, the oriented strands stand proud of the fabric, to enable the asphalt aggregate to penetrate into the meshes and interlock with the strands.

Abstract: In order to provide a suitable packaging system, mesh pieces are deposited across the width of a moving run of flexible wrapping material and are deposited in longitudinally overlapping relationship along the length of the wrapping material, by feeding the mesh pieces on a belt which moves more quickly than the wrapping material; the mesh pieces are ejected from the end of the belt onto the wrapping material. The direction of movement of the wrapping material is inclined downwards so that the trailing ends of the mesh pieces contact the wrapping material before the leading ends contact the preceding mesh piece. The wrapping material, with the mesh pieces on it, is then rolled up under tension into a spiral bale so that the overlapping edges curl down and prevent the mesh pieces slipping out.

Abstract: It is highly desirable to reinforce the grassed surface layer of a sports ground in order to reduce damage to the surface, e.g. from horse racing or from playing football. In order to provide a good surface layer, a biaxially-orientated, integrally-extruded plastics material mesh structure layer is laid on a base of sand strengthened with small, flexible, randomly-placed, plastics material mesh pieces. A top dressing is put on top of the mesh structure layer, grass is seeded or planted, and a machine is then used after the grass has grown to slit the mesh structure layer into pieces 1 which may be e.g. 100.times.100 mm or 150.times.150 mm, each having a number of complete mesh openings. If a piece is caught by a horse's hoof or by an footballer's stud, it may be ripped out, but the whole mesh layer is not ripped out.

Abstract: A drainage system having an at least 2.5 mm thick bi-planar mesh structure drainage core and a filter material against one face and a filter material or impervious member against the other face. The drainage core has generally parallel main strands interconnected by generally parallel subsidiary strands. The main strands are at least twice as tall as the subsidiary strands. The outer faces of the subsidiary strands are coplanar with, and form, one face of the drainage core. The ratio of the free cross-sectional area of each main flow channel to the free cross-sectional area of each subsidiary flow channel, if any, is at least 2.5:1. The drainage core can resist pressures of at least 400 kPa, exhibits a flow fall-off of not more than 20% under an external pressure normal to the faces of 400 kPa.

Abstract: Waisted holes are used when stretching a perforated starting material to form a mesh structure having molecularly-orientated strands. The holes define strand-forming zones which have a center part of greater width than end parts; orientation is initiated in the end parts and travels towards the middle until the whole of the strand-forming zone has been stretched out to form a molecularly-oriented strand. In the molecularly-orientated strand, there are three portions in which the middle of the strand has moved away from the ends of the strand during stretching the same distance as the edges of the strand, these portions corresponding to the end and center parts; in between, the middle of the strand has moved away from the respective end during stretching a different distance to the edges of the strand.

Abstract: An edible composition comprises an integrally extruded net formed of an edible material e.g. a cereal-based, sugar-based or fat-based material. The composition has a novel appearance and unexpectedly good eating qualities. The net may be tubular planar or curved and may be filled and/or coated with a compatible edible material.In the case of a tubular filled net, the net is preferably produced by extending the edible net-forming material through a pair of relatively rotating or oscillating dies having mutually engaging grooved surfaces. When the grooves in one die mate with the grooves in the other die, integral joints between individual strands in the net are formed. When the grooves in one die are separated from the grooves in the other die, the individual strands are formed. A center-filling, which may support the extruded net, is extruded through the center of the net-forming die arrangement to provide a center filling to the tube.

Abstract: A unitary tubular product having an inner layer and an outer layer connected together by a bi-planar mesh formed of helical ribs bonded at their cross-over points is produced in a single coaxial tubular extrusion process, the structure being integrally or confluently extruded. The extruder die head has annular flow channels having closely-spaced die grooves.