Procédé de fabrication d'un produit isolant sous forme de ruban ou de feuillet

摘要

An insulating material in strip on sheet form is made by coating a porous backing material with fibres or flakes of an insulating material e.g. mica, applied electro-phoretically from a suspension thereof. The backing sheet e.g. open weave glass fabric passes in contact with or close to a sheet anode remote from the cathode. A suitable suspension consists of mica flakes, and distilled to which acetone and a dispersing agent e.g. montmorillonite may be added. The dried coating may be treated with a resin binder, and may be stripped of the backing; alternatetively resin may be added to the suspension. A bath of the suspension 11 containing .5 to 10% by wt. of mica flakes is circulated from a reservoir 19 to keep the composition uniform and in which is mounted vertically a cathode 13, and anode 12 spaced from the cathode and extending beyond the surface of the bath. Glass fabric tape 14 passes over the face of the anode to which a D.C. voltage of 100V is applied. The coated tape passes over the face of a pulley 17 which is evacuated internally to dry the tape, and then to a drier 18. For alternative arrangements, a continuously moving belt anode is used Fig. 2 (not shown); the coated tape is pressed by a second tape of open mesh to which the mica coating is transferred Fig. 3 (not shown); and the mica coating after consolidations by pressing with a continuous belt is stripped off Fig. 7 (not shown), in the last form the first coated tape is also in continuous belt form and the sheet anode is substantially horizontal.