Hardened low ash filter paper for quantitative analysis
These filters, made from cotton linters fiber, are put through a washing process and treated with strong acids. Then they are washed in demineralised water to produce high wet strength (appropriate for filtering in high pressure or vacuum conditions) and chemical resistance (suitable to work with acids or alkaline solutions in moderate concentrations). A very low ash-content filter with a <0.015% (the maximum ash contents of these filters is intermediate between CHM® qualitative grades and ashless quantitative grades). A very smooth surface makes easy to recover the whole precipitate after the filtration which is particularly indicated for Büchner filtrations.