| 摘要 |
1,260,363. Epoxy resin coating. DEXTER CORP. 13 March, 1969 [19 March, 1968], No. 13386/69. Heading B2E. [Also in Division C3] Steel sheets are coated with a powdered epoxy resin composition consisting essentially of a linear epoxy resin having a molecular weight of at least 2000 and epoxide equivalency of about 2 and a hardener which is an adduct of trimellitic anhydride with either a polyol containing at least 6 alcohol groups or a polyol containing at least 3 alcohol groups which has been increased in molecular weight to at least 400 by condensation with a lower alkylene oxide. The hardener provides 2 acid groups per OH group of the starting polyol and is used so as to provide approximately one acid equivalent per epoxide equivalent of the resin. The composition also contains 0.2-1.0% by weight of a catalyst, e.g. triphenylphosphine. Suitable polyols are adducts of trimellitic anhydride with mannitol or condensates of propylene oxide and trimethylol propane or pentaerthritol. The coatings may be cured by heating, e.g. for up to 10 minutes at 400‹F. |
