Filter Paper, Whatman Grade 40 / 41 / 42, 125 mm (China)

Description

Filter Paper, Whatman Grade 40 / 41 / 42, 125 mm (China)

Whatman Filter Papers (Grades 40, 41, and 42) are high-purity, ashless qualitative filter papers manufactured from high-quality cotton linters and widely used in analytical and routine laboratory filtration. These filter papers are designed for reliable particle retention with consistent flow rates, making them suitable for gravimetric analysis, sample preparation, environmental testing, and chemical analysis.

All grades feature very low ash content, ensuring accurate weighing and minimal residue after ignition. The 125 mm circular format is compatible with standard laboratory funnels and vacuum filtration setups. Different grades provide varying filtration speeds and particle retention levels, allowing users to select the most suitable option based on analytical requirements.

Common Specifications (All Grades)

Parameter	Specification
Brand Type	Whatman (Equivalent), China
Diameter	125 mm
Shape	Circular
Material	High-purity cotton linters (≥98% alpha cellulose)
Ash Content	Very low (ashless, approx. ≤0.007%)
Quantity per Pack	Typically 100 circles
Application Area	Analytical & general laboratory filtration

Grade Variations & Technical Details

Grade 40 – Medium Flow, General Purpose

Parameter	Specification
Grade	40
Particle Retention	~8 µm
Flow Rate	Medium
Typical Use	Routine filtration, qualitative analysis, general laboratory work

Grade 41 – Fast Flow, Coarse Retention

Parameter	Specification
Grade	41
Particle Retention	~20–25 µm
Flow Rate	Fast
Typical Use	Gravimetric analysis, filtration of coarse precipitates (e.g., Al(OH)₃, Fe(OH)₃), air pollution testing

Grade 42 – Slow Flow, Fine Retention

Parameter	Specification
Grade	42
Particle Retention	~2.5 µm
Flow Rate	Slow
Typical Use	Fine precipitates, gravimetric analysis, cement testing, barium sulfate analysis

Available Variants

• Filter Paper Grade 40, 125 mm
• Filter Paper Grade 41, 125 mm
• Filter Paper Grade 42, 125 mm