| 摘要 |
PURPOSE:To obtain a thermal contractive synthetic resin film which has a good shielding characteristic for electromagnetic waves and a good antistatic characteristic, and which has a thermal contractive characteristic, by which a packing material in a tight binding state can be easily obtained, and a good thermal resistance at the same time, and further which is produced with ease, by a structure wherein the thermal contractive synthetic resin film consists of a thermoplastic synthetic resin having polyethylene chains and a carbon, and in this connection, a bridge structure due to irradiation of an electron beam is introduce therein. CONSTITUTION:In a thermal contractive synthetic resin film consists of 95-50wt.% thermoplastic synthetic resin having polyethylene chains and 5-50wt.% carbon, a bridge structure due to irradiation of an electron beam is introduced into said thermoplastic synthetic resin having the polyethylene chains, and effectiviness of thermal contraction of said thermal contractive synthetic resin is in the range of 10-90% at the softening temperature thereof. For example, a film 100mum thick made of the mixture of 70wt.% polyethylene of low density and 30wt.% acetylene black is irradiated with an electron beam in a nitrogen flow at an acceleration voltage of 175KV, and in an exposure of 10 Mrad to introduce the bridge structure therein. Subsequently, drawing treatment of a magnification of 2.5 is performed perpendicularly to the width at a drawing temperature of 80 deg.C. |
