JIS C 6493:1999 (R2014)

The specification gives requirements for properties of thin polyimide woven glass fabric copper-clad laminated sheet of defined flammability (vertical fire resistance) for use in the fabrication of multilayer printed boards. Laminated sheets covered by this specification have thicknesses (of the base laminate, excluding the copper foil) not greater than 0.8 mm. Although primarily intended for multilayer boards, the materials may be used for single-sided or double-sided printed boards. Polyimide woven glass fabric laminates are available in two types: -- type 1: modified polyimide resin; -- type 2: unmodified polyimide resin. The two types have equal properties except for the glass transition temperature, and therefore this specification differentiates them only in respect of the glass transition temperature.