• Raman Boards

Sigma Diamond Dotted Paper

Raman Boards offers Sigma diamond dotted paper in a range of thickness with a coating of epoxy resin formulation. This product has been developed with capability to coat the resin on one or on both sides of high grade Sigma Press paper. The base paper has been proven for usage, as insulation in transformers and coated paper is completely compatible with transformer oil when thermally aged. The epoxy resin is coated in squares of dimension 9.5mm and is spaced at a distance of 6.7mm between squares. The squares are arranged in a manner that their diagonals lie parallel and perpendicular to machine direction of the paper. The epoxy dots are arranged in such a pattern that ensures an offset relationship exists between the dots on concentric paper layers, thus creating the maximum bonding surface. The thickness of the epoxy resin coating is 0.01mm on each side, ± 0.002mm tolerance and is independent of the base paper thickness. The size, shape thickness and placement of the dots ensure effective vacuum drying and oil impregnation.