In solvent-based systems
Micronized wax can be added to the coating ink by dispersion or grinding, or the wax powder can be made into a wax slurry with 20-30% content, and then added in the required proportion.
1. Temperature control: Except for micronized PTFE wax, other micronized wax products will be dissolved by the solvent at higher temperature, resulting in coarse crystallization, and some of the coarse particles will reach several hundred microns, which cannot be dispersed again. Therefore, the stirring or grinding temperature is best controlled below 45 degrees Celsius. Toluene-based solvent system using wax powder try not to use the grinding process, to avoid the summer production temperature is too high.
2. Solvent selection: polyethylene wax is easily soluble in aromatic, aliphatic and chlorinated solvents; it has smaller solubility in alcohol ether, ester, ethanol and acetone solvents. If you want to make solvent-based wax paste, choose a solvent with lower solubility for micronized wax, such as ethyl acetate.
3. Dispersion method: first stir at a low speed until a vortex is generated, then add the wax powder to the center of the vortex in small batches, and after all the wax powder is added, then increase the stirring speed to 1200rpm and stir fully until it is completely dispersed.
In the aqueous system
It is difficult to disperse the wax powder, so it is generally recommended to make water-based wax paste first, and then add the water-based wax paste into the water-based coating ink. To produce resin-free liquid water-based wax paste, the following steps can be followed.
1. Dissolve 1-2 parts of surfactant or wetting agent in 10-20 parts of water, using warm water will be easier to dissolve, stirring if necessary. After dissolving, continue to add water to 80-90 parts. During this period, you can add a small amount of ammonia to adjust the pH value to 8-9.
2. Turn on the disperser, stir at 300-400 rpm at low speed, and gradually add water-based micronized wax to the water with wetting agent dissolved, the amount of water-based micronized wax added is 20-30 parts, and after all of them are added, turn the mixer to 1200-1500 rpm and stir at high speed for 20-30 minutes. If you use high shear dispersion equipment such as homogenizer, the dispersion effect will be better. At the same time, you can add appropriate amount of defoamer to defoam or wait for the foam to defoam naturally.
3. Turn on the disperser with low speed stirring, add appropriate amount of thickener to the wax slurry and adjust the slurry to the proper viscosity.
Micronized wax added to paints and coatings will have the following characteristics
1. Excellent slip and anti-adhesive properties.
2. Highly resistant to scratching and metal scratches.
3. Acts as a matting agent in wood finishes, soft and smooth to the touch.
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