This filter paper is a calendared, hardened, qualitative low-ash filter paper used to filter fine precipitates with the following qualities:
A very slow, extra dense paper made from 100% cotton linters.
Highly resistant to acid and alkaline solutions.
All paper grades are described by the type of particles retained, in accordance with ASTM Standard Methods. The particle size retention range for this paper is 2-5μm (microns). The filter paper meets or exceeds the standards established by the American Petroleum Institute as published in API Recommended Practice 13B-1 and API Recommended Practice 13B-2.