a fibrous layer impregnated with the phenolic cyanate resin of the present invention the prepreg itself can be used as a single layer which can be crosslinked to form a polytriazine impregnated fibrous layer alternately a composite can be made of at least two adjacent layers connected through resin of each layer the composite can be used prior to curing where the resin is a phenolic cyanate resin or after curing where the resin is crosslinked to form a phenolic triazine type resin a preferred embodiment of the present invention is 10 illustrated in fig1 the a composite 12 comprises three prepreg layers 14 each prepreg layer comprises a fibrous layer the fibrous layer comprises a fibrous network 16 embedded in a phenolic cyanate resin 18 of the present invention a preferred fibrous network is woven fiberglass the phenolic cyanate resin may be cured to form a phenolic triazine the composite 12 can have a polymeric layer 20 adjacent to one or both of its outer surfaces 20 a preferred polymeric layer 20 is polyvinylidine fluoride this polymer is flame resistant and can be printed upon the layer can be printed upon and then a further additional protective layer 24 of a suitable polymer such as polyvinylidene fluoride can be finally applied the polymeric layer 22 and the protective layer 24 can be applied by suitable means known in the art optionally and where heat and pressure are insufficient to provide suitable adhesion to the panel 12 adhesives can be used between at the outer surface 22 fig2 and 3.