Qualitative Filter Papers-Grade 6: 3μm

Whatman gridded filters have clearly defined grid lines spaced at 3.1 or 5 mm intervals.

The special ink used is nontoxic and completely
free from bacterial growth inhibitors.

Whatman black mixed cellulose esters are available plain for automatic colony
counting applications, as well as gridded to assist in manual counting procedures.

Black membranes provide contrast between residue or cell colors and the filter
without having to counter-stain the membrane.

Extremely fast filtering with excellent retention of coarse particles and gelatinous
precipitates such as ferric hydroxide and aluminum hydroxide.

Very useful as a rapid filter for routine clean-up of biological fluids or organic extracts during analysis.

Used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.

Available prepleated as Grade 4V.