The IEC60893/NEMA GPO-3 standard does not mandate a fixed percentage, only assesses the performance of finished products. The following is the typical weight percentage (wt%) of qualified electrical grade board industry
-Glass fiber mat: 55% to 65% wt
-Unsaturated polyester resin: 30-40% wt
-Flame retardant, curing, pigment additives: 3-7% wt
Common reference median values for high-quality boards: fiberglass ≈ 60 wt%, resin ≈ 35 wt%, additives ≈ 5 wt%, density 1.81-1.83 g/cm ³
Important reminder:
1. It is weight percentage wt%, not volume ratio;
2. Low priced and inferior materials will reduce glass fiber, add more inorganic fillers such as calcium carbonate, and cause density deviation, CTI, Decreased arc resistance performance;
3. Customs declaration, MSDS, UL data, * * priority should be given to using the manufacturer's MSDS report values * *, and the above range is a general industry reference.
