Zenpore Qualitative Grade 4 Filter Paper

zenpore qualitative grade 4

  • COARSE RETENTION : Retains coarse and gelatinous precipitates (20~25 μm)
  • FAST PRE-FILTER : Quickly clean-up biological samples and organic extracts, routine clarification
  • WINE MAKING : Filtration of musts
  • HIGH AIR-FLOW COLLECTION : Collect large particulate in fast moving air or fumes

Equivalent to Whatman grade 4/4V, this very fast laboratory filter paper is used for coarse filtration when you need to separate a solid or precipitate from the filtrate.
Made from high purity alpha-cellulose cotton, this standard qualitative lab filter is not intended for ashing.

Flat Grade 4 range Quadrant Grade 4 range Fluted Grade 4 range


  • science : Routine clean-up of insoluble liquids such as biological fluids or organic extracts in labs
  • food : Determination Sodium Chloride in foodstuffs
  • wine : Filtration of musts
  • metalurgy : Determination of silicon impurities in pig iron and steel
  • environment : Fast flowing air and exhausts monitoring when the collection of fine particles is not critical

Coarse Retention

Retains coarse particles and gelatinous precipitates like:

  • Metal hydroxides (Al, Cr, Fe, Mg), Be Oxide
  • Insoluble iron and ore, precipitated Silicates
  • Culture media, and colloidal sediments


  • paper : pure cotton cellulose
  • flow : fast
  • retention : 20~25 micron
  • speed : 15~20 s (10ml DIN 53137)
  • thickness : 140 mm
  • weight : 86 g/m²
  • ash : 0.1%

Flat Discs

Flat Discs are suitable for gravity and B├╝chner low suction vacuum filtration.

∅ 70 mm ∅ 90 mm ∅ 110 mm ∅ 125 mm ∅ 150 mm ∅ 185 mm ∅ 240 mm

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Folded Discs

  • PRE FOLDED QUADRANTS : Save time with funnel-ready quarter folded filter paper
  • FASTER FILTRATION : Prepleated filter papers improve the flow and don't need folding
  • LONGER USE : With more surface area, fluted filter papers increase loading capacity

Quadrant Folded and Fluted Filters saves folding time when filtration is done repetitively. Pre-Pleated Fluted Filters also reduce filtration time by increasing the active filtration surface of the filter.
Both are suitable for gravity filtration in standard funnels. For suction filtration, use flat disks instead.

Folding Type ∅ 125 mm ∅ 150 mm ∅ 185 mm ∅ 240 mm
Quadrant Folded
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Fluted Pleating
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