Plastic petrol can blow moulding - mfd. by co-extrusion of thick compatible inner and thin antistatic outer plastic layer

摘要

A can for the storage and transport of explosive material such as petrol is produced from plastic material by blow moulding. A co-extrusion technique is used to combine at least two plastic layers. The inside layer is compatible with petrol and the outside layer is made of a plastic with a max. surface resistance of 109 ohm at 500V. The percentage weight of the thinner outside layer is not more than 20% of the total can weight. Suitable materials are low pressure or high molecular polyethylene for the inside, and the same with a carbon black admixture for the outside layer. The plastic material with carbon black admixture must be imported and costs 2 1/2 times as much. The new process therefore produces such cans at much lower cost.