ES352813A1 - Improvements introduced in the procedure for continuously preparing leaves or plates. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

A striped sheet is cast on a moving surface by depositing at least one band of a polymerizable resin which is distinguishable from the main resin also deposited on the moving surface. The casting surface comprises a moving belt 1 which is unwound from a roll 2, Fig. 1, to move under an infra-red heater 4, one or more transversely adjustable band applicators 5, Fig. 4, each of which deposits one or more bands of a polymerizable liquid or paste and of predetermined width, the applicators being fed from a reservoir via control valves. The bands pass below infrared heaters 8 which effect partial curing so that the bands are self-sustaining before the main resin is deposited, from a trough 9, Fig. 1. Fibrous reinforcing material 10, e.g. a loose mat, is then deposited on the resin by a belt 12 and is pressed into the resin by tensioning threads 13. A cover sheet 15 similar to the belt 1 is unwound from a roll 16 under infra-red heaters 18 and passes to the pinch rolls 17, 171. The composite sheet 1, 23, 231, 15, Fig. 3B, then passes through a curing and forming oven 19, Fig. 1, to be trimmed and cut by saws 20, 21. The cover sheets 1, 15 may be removed. Each band applicator 5, Fig. 5, floats on the carrier surface and comprises one compartment or several compartments of the same or different widths. The reinforced sheet may be opaque or translucent with opaque or translucent coloured stripes. Unsaturated polymeric esters suitable for use for the sheet forming resin and the stripe material include those prepared by condensing under polymerizing conditions an ethylenically unsaturated dicarboxylic and with a diol containing no ethylenic unsaturation or a dicarboxylic acid containing no ethylenic unsaturation with an ethylenically unsaturated diol or a mixture of ethylenically unsaturated dicarboxylic acids and dicarboxylic acids containing no ethylenic unsaturation with a diol containing no ethylenic unsaturation. Stable diacylchlorides, diesters or anhydrides of the dicarboxylic acids can be substituted in whole or in part for the acid. The curing reaction may be effected by light, X-rays or nuclear radiation. The reinforcing fibre may be asbestos, nylon, cellulose, or glass and may be loose or in cloth, yarn or mat form.