The first step is to ensure that your aluminum powder is thoroughly wetted. If all the aluminum pigment particles are separate and well wetted, you will often achieve an excellent metallic effect. Tech-8892 is an acrylic aluminum silver powder passivator that can significantly improve the dispersibility and chemical resistance of aluminum silver pastes. The recommended initial addition rate is 0.1–3% of the formulation. Since different silver powder particle sizes require varying amounts of dispersant, we recommend conducting gradient tests. We recommend using Tech-58687 polyurethane superdispersant as the dispersant. The next step is to ensure the stability of the silver paste; we recommend adding Tech-9010L at a later stage. Tech-9010L is a rheological modifier that helps prevent the settling of silver powder.

We recommend Tech-5366 for the dispersion of titanium dioxide and inorganic pigments and fillers, and Tech-5041, Tech-5830, and Tech-6202 for the dispersion of organic pigments and carbon black. Ideally, a single wetting and dispersing agent should be able to stabilize all colors; however, in practical applications, it is often necessary to use a combination of two wetting and dispersing agents. Recommended for white and other pigment blends (e.g., white blended with carbon black, or blended with iron oxide red, phthalocyanine blue, etc.). Color stability must be evaluated through a finger-rub test, and stability under high-speed agitation must also be assessed. These blends of white and other colors must also undergo finger-rub and high-speed agitation stability tests after application. The storage stability of each color paste must be tested by storing it in an oven at 50°C for at least three days. After the storage stability test, the color paste must be re-evaluated according to the application criteria established prior to storage. A high-quality colored paint should exhibit a color difference value of less than (△E < 0.5) and demonstrate good leveling; the gloss and color must remain consistent before and after storage.

A common method is to add Tech-504 to the coating. Tech-504 is a controlled-flocculation wetting and dispersing agent that forms a network structure between pigment particles and its own particles; this network structure prevents pigment floating. Tech-504 can be added later in the process or during the grinding and slurry preparation stage. At higher concentrations, Tech-504 may increase the viscosity of the coating system and may affect gloss.

To overcome pinholes and improve the wetting properties of coatings, it is necessary to reduce the surface tension of the liquid coating; Tech-1399 is a specialized polymer-based leveling agent that can slightly reduce the surface tension of the coating. Compared to standard acrylic leveling agents, it offers greater surface tension reduction and superior resistance to pinholes, while providing excellent leveling performance without any adverse effects on surface gloss or DOI values. For use in clear coats, we recommend Tech-1068 polyester leveling agent, which offers excellent coating compatibility and film transparency.

We recommend adding an adhesion promoter to improve adhesion to metal substrates. Tech-7200 is a hyperbranched polyester-based adhesion promoter recommended for use in acid-catalyzed systems, such as solvent-based polyester/amine systems. It can be added later in the formulation, and a 1% addition can significantly improve adhesion to galvanized steel. The recommended starting addition level is 1%. We recommend conducting gradient tests.

Tceh-8225N is a product based on dodecylbenzenesulfonic acid (DDBSA) that has been blocked with an organic amine. It exists as an amine salt at room temperature, reducing the risk of self-crosslinking in storage tanks. When heated in an oven, it releases protonic acid. Compared to fully blocked sulfonates (such as pyridine-blocked p-toluenesulfonic acid), it undergoes more active decapitation and is particularly well-suited for polyester/amino systems in coil coatings in terms of catalytic performance and safety.