Overview and film-forming mechanism of water-based coalescents!

01 Overview of Coalescent Agents

The film-forming aids of water-based coatings, also known as coagulants, coalescing agents, film-forming aids or co-solvents, can dissolve and swell the polymer particles in the emulsion, so that the particles can also change with moisture at lower temperatures.

Water-based coating film-forming additives are widely used in architectural coatings (latex paint), water-based automotive coatings and automotive refinish coatings, water-based electrophoretic coatings, water-based marine coatings, water-based container coatings, water-based anti-corrosion coatings, water-based industrial coatings, water-based adhesives, water-based woodware Coatings, water-based coil and coil coatings, water-based screen printing inks, water-based gravure inks, water-based flexo inks, UV water-based paint inks, and more .

02 Selection criteria for coalescents

The ideal coalescent should have the following properties:

(1) The film-forming aid must be a strong solvent for the polymer, has excellent film-forming efficiency for a variety of water-based resins, and has good compatibility, and can reduce the minimum film-forming temperature of water-based resins.

03 Film-forming mechanism of water-based coatings

The film-forming process of water-based paint is more complicated, and it has to go through a process from dispersed polymer particles to agglomeration of each other into a whole

(1) The particles gradually move closer to the filling process.

04 Usage and dosage of film-forming aids for water-based coatings

Polymers such as emulsions or dispersions generally have a glass transition temperature Tg above room temperature

The amount of coalescent agent added depends on the amount of emulsion or aqueous dispersion in the formulation and the glass transition temperature Tg