Batch Consistency Across Acid Value, Colour, Viscosity and Water

Acid-value movement may come from a different monoester-to-diester ratio or from hydrolysis generating free acid. Rising water and free acid often accompany storage instability, equipment corrosion and adhesion variation.

Colour depends on raw materials, purification and storage temperature. Light-coloured and clear systems need trend monitoring and yellowing data, not only a current upper limit.

Trend each lot for acid value, colour, viscosity, density, water, free acid and inhibitor. Investigate sustained one-way drift even while every individual result remains in specification.