Patent GB-740980-A (GB)
Title: Improvements in and relating to strippable paint
IPC: B05D5/00
Filed: 1952-11-04
Abstract: Surfaces, e.g. of ships, which are subject to radioactive contamination, are coated prior to contamination with a solution comprising the reaction products of styrene and castor oil which have been caused to react in the presence of a solvent until near the point of gelation.  An exemplary coating composition is made by gently boiling together styrene, dehydrated castor oil and xylene under a reflux condenser for up to 25 hours, the period being such that the product is still a free-flowing liquid although near the stage when gelation would occur; it is then cooled rapidly, stored in the dark, and diluted with xylene to form a varnish.  Chloroform may be added just before application, to cause more rapid gelation and setting.  Pigmented mixtures comprising the styrene-castor oil reaction products together with (a) titanium white and methyl ethyl ketone, (b) zinc oxide, ultramarine, cyclohexanone, and methyl isobutyl ketone, (c) carbon black, xylene and methyl ethyl ketone, and an undercoating for application to unpainted steel comprising the reaction mixture, castor oil, red lead, cyclohexanone and methyl ethyl ketone are also described.ALSO:Surfaces, e.g. of ships, which are subject to radioactive contamination, are coated prior to contamination with a solution comprising the reaction products of styrene and castor oil which have been caused to react in the presence of a solvent until near the point of gelation; after contamination, a coat of a mixture of a resinous substance and an organic solvent is applied thereover, which causes the first coat to wrinkle and lose its adherence, so that both may be stripped off together.  The second coating may be charged with wood chippings, sawdust, paper, hessian or other fibrous material.  Alternatively, a resin solution may be dried on to paper or card, which may then be cut into small pieces, and projected by means of a cement gun or the like, together with an appropriate solvent.  An exemplary first coating composition is made by gently boiling together styrene, dehydrated castor oil and xylene under a reflux condenser for up to 25 hours, the period being such that the product is still a free-flowing liquid; it is then cooled rapidly, stored in the dark, and diluted with xylene to form a varnish.  Pigmented mixtures comprising the styrene-castor oil reaction products, together with (a) titanium white and methyl ethyl ketone, (b) zinc oxide, ultramarine, cyclohexanone, and methyl isobutyl ketone, (c) carbon black, xylene and methyl ethyl ketone, and an under-coating for application to unpainted steel, comprising the reaction mixture, castor oil, red lead, cyclohexanone and methyl ethyl ketone are also described.  Secondary coating compositions comprise polystyrene and toluene; rosin, lanoline and toluene; and pitch, light lubricating oil or fuel oil, and toluene.  Alternatively, long lengths of thick paper or thin strawboard may be coated with a molten mixture of rosin and wool grease, cooled, reeled, and cut into small pieces, which may be projected by a cement-type gun, together with a solvent, which may be a mixture of crude toluene and creosote.