This is a cellulose based paper Winding Wire is widely used for conductor insulation in oil filled transformers. There are various grades of cellulose paper such as:
Standard Kraft Paper & Thermally upgraded Kraft Paper
0.40 mm, 0.50 mm, 0.63 mm, 0.75 mm, 1.00 mm, 1.25 mm
Thermally upgraded Kraft Paper
Calendered paper and thermally upgraded paper are two different qualities of the paper. Upgrading is achieved by adding nitrogen to the paper pulp. Nitrogen replaces the oxygen which otherwise oxidizes and ages the paper at high temperature.
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