Professional Detailing2 min read

Pendant-Drop Density Inputs: Identify Both Phases

Pendant-drop analysis requires the relevant density difference between the drop and surrounding phase. A default density value should not be assumed correct for every coating liquid or liquid-liquid system.

Updated · NANOLAB Knowledge

The key distinction

KRUSS identifies density difference as an input to the calculation. The laboratory should document the phases, temperature and source of the density information so the reported tension can be interpreted and reproduced.

Practical checks

  1. Identify the drop liquid and surrounding phase.
  2. Record the density basis used by the laboratory.
  3. Resolve inconsistent inputs before comparing reports.

Example

Illustrative example: a liquid-liquid test is analysed using settings intended for a drop in air. The instrument may still produce a number, but the input configuration needs review before that number supports a product conclusion.

Scope and limits

Do not change density settings to obtain an expected result. This guide does not supply density values for NANOLAB products or establish a surface-tension acceptance limit.

Related guidance

Technical references: KRUSS: pendant-drop method. These sources describe their stated methods or products; they do not certify NANOLAB products or establish compatibility with an unlisted surface.

Ask NANOLAB about the exact product and intended use. Use the current product documentation for formulation-specific instructions.