These quantitative filter papers are made from refined pulp and linters. They are purified in a highly developed clean-up process to remove organic and inorganic impurities. This ensures a low ash content of <0,01 %. They are consistent performance and give safe results in gravimetric analyses.

• Very low ash content
• Suitable for gravimetric, quantitative analysis
• Contamination-free filtration

Grade MN 640 dd 'green ribbon' is an ashless, slow filter paper which is slightly less retentive than MN 640 d.
Grade MN 640 d 'blue ribbon' is an ashless, slow filter paper with very fine particle retention. Standard paper for critical gravimetric analysis of fine precipitates like barium sulfate or metastannic acid.

Grade MN 640 de is an ashless, very slow filter paper for the filtration of extremely fine particles in quantitative range.

Grade MN 640 m 'white ribbon' is the classic, general purpose, ashless filter paper with medium speed and medium retention. Typical applications include gravimetric analysis for components, quantitative determinations of sediments and high purity clean up procedures.
Grade MN 640 md 'red ribbon' is an ashless filter paper, which is slightly more retentive than MN 640 m with corresponding increase in filtration time.

Grade MN 640 we is the fastest quantitative filter paper with highest flow rate. It is used for example in analytical procedures of samples with coarse or gelatinous particles.
Grade MN 640 w 'black ribbon' is a fast, ashless filter paper. Recommended for analytical procedures involving coarse particles or gelatinous precipitates.