| 摘要 |
The general purpose electrical ignition system based on protected pyrotechnical primer according to the present invention has a primer (1) surrounded by a layered polymeric 7wrapper (3) composed of an external closing layer (4) with thickness in the range of 0.05 to 3 mm, made of heat shrinkable polymer or copolymer, and an internal sealing layer (5) with thickness in the range of 0.05 to 3 mm, made of polymeric melt adhesive. The material of said external closing layer (4) is preferably a semi-solid radiation-cross linked polyolefin, modified fluoroelastomer or flexible fluoropolymer. The material of said internal sealing layer (5) is one-component or two-component melt adhesive. A process for preparing the above-described general-purpose electrical ignition system is characterized in that, there is prepared an external closing layer (4) of a layered polymeric wrapper (3) in the form of a hollow thin-walled cylinder or a hollow concave thin-walled figure closed on one side. Subsequently, melt adhesive forming an internal sealing layer (5) is then applied simultaneously or afterwards from inside on the external closing layer (4) at a temperature in the range of 90 to 160 degC. After the temperature of said internal sealing layer (5) drops down below 50 degC, a primer (1) is inserted in the interior of so performed layered polymeric wrapper (3) and subsequently by the action of temperature in the range of 90 to 250 degC within a furnace or a thermal drying tunnel, the internal sealing layer (5) melts and the external closing layer (4) of the layered polymeric wrapper (3) shrinks around the primer (1) such that hermetical sealing hereof is performed. |
