A heat-resistant release sheet is configured to be disposed, when a resin or a target including a resin is used in a step involving heating and melting of the resin, between the resin or the target and a member to be brought into contact with the resin or the target to prevent direct contact between the resin or the target and the member. The sheet includes a skived sheet including polytetrafluoroethylene (PTFE) or a modified PTFE. A content of a tetrafluoroethylene (TFE) unit in the modified PTFE is 99 mass % or more. In each of two directions being in-plane directions of the heat-resistant release sheet and being perpendicular to each other, a rate of dimensional shrinkage induced by heating at 175° C. for 30 minutes is more than 0%. The sheet includes the skived sheet including the heat-resistant resin but prevents occurrence of problems attributable to inclusion of the skived sheet.

A heat-resistant release sheet is configured to be disposed, when a resin or a target including a resin is used in a step involving heating and melting of the resin, between the resin or the target and a member to be brought into contact with the resin or the target to prevent direct contact between the resin or the target and the member. The sheet includes a skived sheet including polytetrafluoroethylene (PTFE) or a modified PTFE. A content of a tetrafluoroethylene (TFE) unit in the modified PTFE is 99 mass % or more. In each of two directions being in-plane directions of the heat-resistant release sheet and being perpendicular to each other, a rate of dimensional shrinkage induced by heating at 175° C. for 30 minutes is more than 0%. The sheet includes the skived sheet including the heat-resistant resin but prevents occurrence of problems attributable to inclusion of the skived sheet.

A stretch film (1) contains an olefin elastomer and an inorganic filler (3). Stress at 50% elongation is 6.0 N or more and 15.0 N or less, and moisture permeability is 1000 g/(m.sup.2.Math.24 h) or more.

A stretch film (1) contains an olefin elastomer and an inorganic filler (3). Stress at 50% elongation is 6.0 N or more and 15.0 N or less, and moisture permeability is 1000 g/(m.sup.2.Math.24 h) or more.

A heat shrinkable film shows a heat shrinkage rate in the direction perpendicular to the main shrinkage direction that is not high even at high temperature and is printable thereon. The heat shrinkable film includes a polyester resin, wherein the heat shrinkage characteristics in the direction perpendicular to the main shrinkage direction satisfy the following Relationships 1 and 2:
−15≤ΔT.sub.70-65≤0  Relationship 1
0≤ΔT.sub.100-95≤5  Relationship 2 wherein ΔT.sub.X-Y is a value obtained by subtracting heat shrinkage rate of the heat shrinkable film in the direction perpendicular to the main shrinkage direction after the heat shrinkable film is immersed in water bath for 10 seconds at Y° C. from heat shrinkage rate of the heat shrinkable film in the direction perpendicular to the main shrinkage direction after the heat shrinkable film is immersed in water bath for 10 seconds at X° C.

An integral polymer grid with a plurality of interconnected, oriented polyethylene terephthalate strands and an array of openings therein is made from a polyethylene terephthalate sheet-like starting material having holes or depressions therein that form the openings when the sheet-like material is uniaxially or biaxially stretched. The grid has a higher tensile strength to weight ratio and a higher creep reduced strength to weight ratio than corresponding ratios associated with a grid made from a non-polyethylene terephthalate starting material.

An integral polymer grid with a plurality of interconnected, oriented polyethylene terephthalate strands and an array of openings therein is made from a polyethylene terephthalate sheet-like starting material having holes or depressions therein that form the openings when the sheet-like material is uniaxially or biaxially stretched. The grid has a higher tensile strength to weight ratio and a higher creep reduced strength to weight ratio than corresponding ratios associated with a grid made from a non-polyethylene terephthalate starting material.

A method for producing a phase difference film is provided. The phase difference film consisting of a resin C contains a copolymer P containing a polymerization unit A and a polymerization unit B, and includes a phase separation structure that exhibits a structural birefringence. The phase separation structure includes a phase including as a main component the polymerization unit A and another phase including as a main component the polymerization unit B. The phase difference film has an NZ factor of greater than 0 and smaller than 1. The method comprises: forming a single layer film of a resin C; and causing phase separation of the resin C in the film, which includes a step of applying to the film a stress along a thickness direction thereof.

An integral geogrid includes a plurality of interconnected, oriented strands having an array of openings therein that is produced from a coextruded multilayer polymer sheet starting material. By virtue of the construction, the coextruded multilayer sheet components provide a crystalline synergistic effect during extrusion and orientation of the integral geogrid, resulting in enhanced material properties that provide performance benefits to use of the integral geogrid in soil geosyuthetic reinforcement.

An integral geogrid includes a plurality of interconnected, oriented strands having an array of openings therein that is produced from a coextruded multilayer polymer sheet starting material. By virtue of the construction, the coextruded multilayer sheet components provide a crystalline synergistic effect during extrusion and orientation of the integral geogrid, resulting in enhanced material properties that provide performance benefits to use of the integral geogrid in soil geosyuthetic reinforcement.