Thermo Established Diamond dotted paper (DPP) for transformer
It is also known as DDP. The use of this B-stage resin coated paper increases the short circuit strength of distribution transformer coils. It is produced by coating modified epoxy resin in diamond dot patterns on electrical insulating paper. The size of the dots are carefully designed to avoid interfering with vacuum drying and oil impregnation. This type of presspaper is treated chemically and included nitrogen content to get a upgraded thermo performance.