This section of IEC 61 249 establishes the requirements for the characteristics of cyanate ester, brominated epoxide, modified or unmodified woven E-glass laminate sheets, which are defined by their flame resistance (as determined by the vertical burning test) and are copper-clad. These sheets are available in thicknesses ranging from 0.05 mm to 3.2 mm. The flame resistance rating is attained by incorporating brominated flame retardants as an integral component of the epoxide polymer structure. The minimum glass transition temperature is set at 160 °C. Certain property requirements may be categorized into multiple performance classes. It is necessary to specify the desired class on the purchase order; otherwise, the default material class may be supplied.
