North Korea What are the Free of silicone defoamers for paints(1)

North Korea Selection of antifoaming agents for different applications:

hardening

Defoaming mechanism of hydrophobic solid particles
Hydrophobic solid particles in the foam system will first attract the hydrophobic end of the surfactant, making the hydrophobic solid particles become hydrophilic, thus reducing the concentration of surfactant in the foam film and promoting the foam to burst. This defoaming mechanism cannot explain the action mechanism of other defoaming agents, which is too one-sided. [4] Other reasons for the bursting of foam are the impact caused by the expansion of defoamer, the solubilization of surfactant and the collapse of electrolyte, and the bursting of electric double layer on the liquid film surface. [4] It can be seen from the above defoaming mechanisms that each defoamer has different emphasis on different foam systems, but defoaming is achieved by destroying the stability factors of foam

Flat coating

Features: Low viscosity, low defoaming pressure

Recommendation: Mineral oils or mineral oil modified polyethers

dispersant

Elastic coating

There are many types of leveling agents, and the types of leveling agents used for different coatings are also different. High boiling solvent or butyl cellulose can be used in solvent based finishing agents. Surfactants or polyacrylic acid, carboxymethyl cellulose, etc. are used in water-based finishing agents.

Features: High viscosity, high Free of silicone defoamers pressure

Recommendation: Polyether modified silicone

Surface coating and film covering adhesive

Recommendation: Polyethers, which can effectively prevent surface defects and have a small impact on gloss

wetting

Water in Water Colorful

high

Features: More surfactants, stable foam

North Korea Recommendation: Use polyethers or mineral oil to modify polyethers

Leveling agent is a commonly used coating additive that can promote the formation of a flat, smooth, and uniform coating film during the drying process. A class of substances that can effectively reduce the surface tension of finishing fluids and improve their leveling and uniformity. It can improve the permeability of the finishing liquid, reduce the possibility of spots and stains during brushing, increase coverage, and make the film formation uniform and natural. Mainly surface active agents, organic solvents, etc.

Precautions for use of paint Free of silicone defoamers:

Before use, stir thoroughly and mix evenly; Adding the paint while stirring; Before use, it is generally not diluted with water; The dosage should be appropriate. Excessive dosage can cause shrinkage, edge shrinkage, poor brushing performance, and other problems; Too little dosage leads to poor defoaming effect; Add it in two stages, namely, add it in the grinding stage and the paint mixing stage, generally accounting for half of the total amount each time. Use defoaming agents with good foam suppression effect in the grinding stage, and use defoaming agents with good foam breaking effect in the paint mixing stage