Role of a coalescent in chemistry
A coalescent, or coalescing agent, helps polymer particles join into a continuous film. In a latex paint, water carries separate polymer particles. As the water evaporates, those particles move together; a suitable coalescent softens them so they can fuse. Eastman: film formation ↗
How it works
The minimum film-forming temperature (MFFT) is the lowest temperature at which a dispersion forms a coherent film. A coalescent can lower that temperature. Polymer glass transition temperature (Tg), the binder and drying conditions influence the result. Some paints form films without added coalescent at room temperature; others need it. Eastman: MFFT and coalescence ↗
Main uses
- Paints and coatings: supporting film formation, particularly when application temperatures are low.
- Adhesives, sealants and printing inks: supplier products may have these applications, but the function and grade must be checked for the specific system.
Why film formation matters
Incomplete coalescence can leave a porous or weak film. Better particle fusion can improve scrub resistance, washability and gloss. These outcomes depend on the complete formulation and drying conditions. A coalescent is not mandatory in every dispersion. Eastman: film integrity ↗
Examples to investigate
Eastman Texanol™ ester alcohol is a conventional latex-paint coalescent. Its supplier also lists coatings, adhesives and printing-ink applications. Texanol product information ↗
Eastman Optifilm™ enhancer 400 is a nonvolatile coalescent. Its manufacturer’s technical guide discusses selecting a dose from MFFT measurements and then checking the finished paint. Optifilm technical guide ↗
SUPPLIER EXAMPLE
Loxanol® CA 5310
BASF describes CA 5310 as a renewable-raw-material coalescent that stays in the paint film, providing a lasting coalescing effect. The supplier reports low odor, improved scrub resistance and low-temperature film performance. These are supplier claims, not an EcoSafe assessment. BASF product page ↗
Suggested applications
- ACE
- Air barriers
- Construction adhesives and sealants
- EIFS
- Industrial coatings
- OPV
- Roof coatings
Application labels follow BASF’s page. Confirm the current grade documents and intended use with the supplier. Open the material profile →
Choosing a coalescent
Start with the intended application temperature and the binder’s MFFT. Test several coalescent levels, then evaluate film performance. An efficient MFFT reduction alone does not establish an interchangeable replacement. Eastman: dose selection ↗
Coalescent is a function, not a sustainability label. Check the exact grade’s safety data, emissions test basis and finished-product performance before making a claim.
Explore the Formulators Guide →Educational summary based on manufacturer references checked November 3, 2026. Supplier statements retain their product and application scope.