| 摘要 |
1382611 Coated fasteners USS ENGINEERS & CONSULTANTS INC 3 Jan 1972 [19 Jan 1971] 178/72 Heading B2E [Also in Division C3] Driven metal fasteners for frictional insertion, e.g. nails, are provided with hard smooth coatings of compositions comprising (1) 50 to 80 weight per cent of a resin which is hard at room temperature and has a softening point of 60 to 163‹C and (2) 20 to 50 weight per cent of an ethylene copolymer comprising 60-90 weight per cent ethylene and 10 to 40 weight per cent of ethylenically unsaturated carboxylic acid or ester thereof free of groups which are reactive with the resin. Specified components are (1) rosin, modified rosin, rosin derivatives, petroleum resins, coumarone-indene resins cyclopentadiene resins, terpene resins, coal tar pitch and fossil resins such as dammars, East India, copals, accroides and sandarac resins; and (2) copolymers of ethylene with acrylic, methacrylic crotonic, isocrotonic, vinylacetic or allylacetic acid, allyl or vinyl crotonylacetate, or allyl, methyl, ethyl or butyl acrylate. The coatings may be applied from aqueous solutions or dispersions, e.g. prepared by dispersing the resin and copolymer, or organic solvent solutions thereof, in an aqueous medium, optionally in the presence of a volatile base, e.g. ammonia or an amine, surfactants and antifoam agents, e.g. butanol. In examples nails are coated with compositions comprising toluene solutions of pentaerythritol ester of rosin, petroleum resin, terpene resin and petroleum resin/terpene resin mixtures together with diacetone alcohol, dispersed in water containing ethylene/acrylic acid copolymers solubilised with ammonia and the coatings dried. |
