Patent GB-938141-A (GB)
Title: Adhesive process and epoxy resin primar for polyurethane resinous materials
Inventor: PHILLIPS LESLIE NATHAN
IPC: C09D175/04
Filed: 1959-01-30
Abstract: A two-stage coating process for coating articles (e.g glass-fibre/unsaturated polyester resin laminates, wood and metal) with polyurethanes comprises using as a primer before applying the polyurethane an epoxy resin plus 2-15% by weight of the resin of a hotsetting tertiary amine.  The epoxy resins are bisphenol A/epichlorhydrin reaction products.  The amines disclosed are cetyl di methylamine and N-ethyl- and N-coco-morpholines. Solvents specified are toluene, and ethylene glycol mono (m) ethyl ether acetate, or mixtures thereof.  Cellulose acetate butyrate may also be added to either coating.  Various polyurethanes, derived by reacting linear polyesters with diisocyanates and dissolved in solvents containing curing agents (e.g. SnCl4, SbCl3, SbCl5, N-coco-morpholine and N,N,N1,N1-tetrakis-(2-hydroxy propyl) ethylene diamine), are described in Examples 1-5 (see Group IV(a)).  In the examples two coats of the primer were applied, followed by 2, 6 or 10 coats of the polyurethane.  After each stage was completed, the coating was cured at temperatures of 70 DEG -90 DEG C. for 40 minutes to 3 hours.ALSO:A two-stage coating process for coating articles with polyurethanes comprises using as a primer an epoxy resin plus 2-15% by weight of the resin of a hot-setting tertiary amine.  The epoxy resins are bisphenol A/epichlorhydrin reaction products. The amines disclosed are cetyl dimethylamine and N-ethyl- and N-cocomorpholines.  Solvents specified are toluene, and ethylene glycol mono (m) ethyl ether acetate or mixtures thereof. Cellulose acetate butyrate may also be added.  The coatings were applied to glass-fibre unsaturated polyester resin laminates, wood and metal.  The following polyurethanes are described in the examples:- (1) A polyethylene adipate of M.W. approx. 2,000 is dissolved in toluene, dehydrated, reacted first with 1,5-naphthylene diisocyanate and then with 2,4-toluylene diisocyanate, and mixed with a solution of SnCl4 in ethylene glycol monoethyl ether acetate.  (2) A polyester derived from ethylene glycol, neopentyl glycol and adipic acid is similarly treated, except that after the isocyanate treatment, it is filtered through nylon cloth treated with a toluene solution of acetyl chloride, and SbCl3 is used instead of SnCl4; cellulose acetate butyrate is also added.  (3) as (2), but SbCl5 is used instead of SbCl3.  (4) A polyester derived from sebacic acid, neopentyl glycol and ethylene glycol is dehydrated by azeotropic distillation with toluene, yielding a toluene solution, is reacted first with 4,41-diphenyl methane diisocyanate and then with 2,4-toluylene diisocyanate, and mixed with a solution of N-coco-morpholine in ethylene glycol mono-ethyl ether acetate.  (5) as (4), except that the amine was N,N,N1,N1-tetrabis-(2-hydroxy propyl) ethylene diamine. Two coats of the primer were applied in the examples followed by 2, 6 or 10 coats of the polymethane.  After each stage was completed, the coating was cured at temperatures of 70 DEG -90 DEG C. for 40 minutes to 3 hours.