| 摘要 |
<p>1,185,902. Laminated antifouling covering. B. F. GOODRICH CO. 30 March, 1967 [31 March, 1966], No. 14512/67. Heading B5N. [Also in Division B7] A covering resistant to marine fouling organisms comprises a reservoir layer 12 of material containing a toxic agent for poisoning or repelling marine fouling organisms, and a toxic agent transfer control layer 14 of elastomeric material between the layer 12 and the surface of the covering which is exposed to the fouling organisms in use, the transfer control layer 14 being capable of regulating the transfer of the toxic agent from the reservoir layer 12 to the outer face of the layer 14 to provide thereon a desired minimum concentration of the toxic agent. Both the reservoir layer and the control layer may be elastomers selected from neoprene, isobutylene-isoprene copolymers, styrene-butadiene copolymers, cis-polybutadiene, ethylenepropylene copolymers, polyether- and polyesterurethanes, butadiene-acrylonitrile copolymers, natural rubbers, epichlorohydrin rubbers, and silicone rubbers. The elastomers are preferably vulcanizable or cross-linkable with sulphur, sulphur-containing compounds, metal oxides, peroxides, or amines. The reservoir layer may be cellular e.g. an open celled polyurethane or p.v.c. foam. The elastomers used are preferably solvents for the toxic agent which is preferably an organotin compound of the formula (R 3 Sn) n X where R is an alkyl or phenyl group, n is 1 or 2 and X is a sulphide, oxide, chloride, fluoride, bromide, chromate, sulphate, nitrate, laurate, hydroxide, acetate, octanoate, resinate, dimethyl dithiocarbamate, naphthenate, paravinyl benzoate, acrylate, methacrylate, hydride, isooctylmercaptoacetate, or methoxide radical. Preferred compounds are exemplified. Preferably the layer 14 has a low solubility limit and the layer 12 a high solubility limit for the toxic agent, and the layer 12 may be super-saturated therewith. The layers may be produced by adding the toxic agent as a dry powder or oil to the elastomer at the polymerization stage or to a solution of the elastomer. The elastomers may be extruded, rolled, or moulded to shape, or calendered on to fabrics. The layers 12, 14 may be vulcanized together or secured by adhesive, and then vulcanized. The layers may be further laminated to metal, wood, plastics, fabrics, concrete or fibreglass, and are preferably secured as sheets or strips to ship hulls, buoys, or pier piling. In other examples the control layer envelopes the reservoir layer, or pads of the reservoir layer material lie between and are spaced by sheets of the control layer material.</p> |
