Abstract
The paper deals with the use of plastics materials based chiefly on polymethylmethacrylate and polystyrene for transparent and translucent lighting enclosures. The development is briefly traced from the first introduction of shaped acrylic sheet for fluorescent reflectors and diffusers to the highly complicated range of light controlling enclosures in production today. The manipulation of acrylic sheet is described comparing the old blowing techniques to the present method of producing modern re-entrant and deep drawn shapings. The introduction of modified polystyrene and its effect on the market due to new manufacturing methods is discussed. Extrusion by ring and profile dies and methods of post-extrusion treatment of both sections and sheet to give prismatic patterns are described, and injection moulding practice is discussed together with the possibilities of the production of large area moulding by this method. Some speculation is made on future plastics developments affecting the lighting industry.
Get full access to this article
View all access options for this article.