| 摘要 |
PURPOSE:To form a laminated sheet excellent in flame retardancy and good in punching quality, by using a phenolic resin containing a specified modified halogenated epoxy resin as a flame retardant as a resin composition for impregnating bases. CONSTITUTION:A flame retardant is obtained by reacting (a) a halogenated epoxy resin having two epoxy groups in the molecule (e.g., dibromoneopentyl glycol glycidyl ether) with (b) tetrabromobisphenol A at an epoxy group/hydroxyl group molar ratio of about 6-1.2 and reacting the reaction product with (c) an unsaturated higher fatty acid amido or imido group-containing compound of the formula (wherein R and R' are each a 16-18C unsaturated hydrocarbon grou) in an amount substantially equimolar to that of the residual epoxy groups. A substrate is impregnated with a varnish obtained by mixing the above flame retardant with a resol phenolic resin to form prepregs, which are laminated as usual to obtain a laminated sheet.
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