Whatman
Grade 201 Cellulose Filter Paper, 18.5cm Circle, 100/Pk SKU: 5201-185

Qualitative Filter Paper - 5201-185

Pre-filtering turbid samples before instrumental analysis needs a paper grade that removes interfering particles while maintaining reasonable flow rates. Uniform pore distribution across the sheet area ensures consistent particle capture from center to edge during gravity filtration. Lot-level verification of retention, thickness, and ash content ensures predictable performance when scaling from method development to routine analysis.

Key Filter Paper Characteristics

• Particle retention rating of Medium Fine defines the separation threshold for the application, determining which solids are captured and which pass through.
• Standard basis weight and thickness specifications provide predictable packing density for volumetric calculations in gravity funnels.
• Wet strength sufficient for gentle handling during precipitate transfer while maintaining the rapid flow rates of qualitative grades.
• Smooth surface finish supports clear visual inspection of retained material and clean separation from the collected filtrate.
• Wet-strengthened construction provides the mechanical durability needed for technical filtration applications under sustained vacuum.

If your workflow includes both routine clarification and specialized quantitative methods, stocking this versatile grade reduces your inventory complexity. In these cases, sheet-to-sheet consistency means your training investment carries forward as new staff learn the same predictable filtration behavior. Make the decision for consistency and reliability, ensuring that your laboratory maintains its reputation for high-quality, error-free output.

Diameter

18.5cm

Flow Speed

Slow

Folded/ Fluted/ Pleated

No

Grade

201

Hardened (Yes/ No)

No

Material

Cellulose Fiber

Nominal Basis Weight (g/ m²)

75g/m²

Particle Retention

Medium Fine

Pore Size (µm)

7.0-14.0

Qualitative/ Quantitative

Qualitative

Sterility

Nonsterile

Wet Strengthened (Yes/ No)

Yes

Wettability

Hydrophilic

• Polymer Filtration - Clears particulates from polymer solutions before molecular weight determination by viscometry or GPC.
• Pigment Screening - Separates undispersed colorant particles from coating formulations during color development and QC testing.
• Paint and Coatings QC - Removes gels and undispersed pigment from coating samples prior to color measurement and viscosity testing.
• Botanical Extraction - Separates plant tissue debris from aqueous and solvent extracts during natural product preparation workflows.
• Teaching Laboratory - Provides consistent and economical filtration media for student exercises in analytical and general chemistry.
• Beverage Testing - Filters wine, beer, and juice samples before clarity and color measurements in food quality control laboratories.