These CHM® filter papers are used for quantitative analysis and designed for preparation of samples and gravimetric analysis. They are made of refined pulp and linters with virtually 100% of alpha-cellulose content. These filter papers are guaranteed free of possible residual acids used in some production methods. Extremely low percentage of ash content (maximum ash content of <0.007%). Ashless filter papers for quantitative analyses are suitable for Büchner funnels and for filtration under vacuum.