In automotive coatings, highly chromatic paint finishes are desired which appeal to consumer tastes. Transparency is also important to highlight effect pigments which contribute to the glamour of the coating. The use of high color carbon black and transparent organic pigments is required to achieve these highly chromatic paint finishes.
These types of pigments are typically difficult to disperse and often characterized by high dispersion viscosity, problematic viscosity stability, and typically require extensive, high energy milling to achieve the desired coloristics. All of this makes for high production costs, resulting in reduced margins.
Some factors which make the dispersion of these pigments difficult include: surface chemistry, and high surface area / small particle size. To address this challenge, a novel dispersing agent has been developed by BASF, incorporating proprietary pigment affinic chemistry, which enables successful dispersion of these difficult to disperse pigments, resulting in less dispersant demand to achieve excellent pigment stabilization and lower resulting dispersion viscosities as well as improved color performance.
In performance tests with high color carbon black, and a variety of transparent organic pigments, this novel dispersant has demonstrated high efficiency for stabilizing the pigments in solvent based dispersions. Significantly less dispersant is required to achieve low dispersion viscosities than with industry benchmarks. This also translates to improved coloristics-e.g., improved jetness and undertone in black colorants made with this new dispersant vs. industry benchmark performance.
In addition to enhanced pigment affinic chemistry which enables best in class dispersion performance with said pigment types, the new dispersant incorporates functionality which enables it to cross link into the resin matrix with polyurethane and melamine chemistries. This capability enables the dispersant to truly become part of the coating as opposed to a free floatingconstituent in the formulation that is not truly bound to the whole. This eliminates the possibility of migration of the dispersant after coating application and more importantly, it offers significant improvement to film / coating durability over non-crosslinkable dispersant technology.
Lastly, the product has been designed to be 100% active solids, which offers formulators flexibility in terms of VOC constraints of their coating formulation. In addition, the product can be cut in a variety of solvents to suit the formulation system.
In summary, this new, novel dispersing agent offers improved pigment stabilization of difficult pigments yielding more efficient dispersion processing and improved coloristics of the resulting dispersion; ability to crosslink into specific chemistries common to automotive coatings which enables significantly improved coating durability; and low VOC footprint.
Tony is responsible for Transportation, Industrial, Furniture, and Flooring market segments and is the primary expert for dispersing agents within the BASF Formulation Additives team. He has been in the coatings industry for 31 years, with the last 9 years at BASF. Prior to BASF, Tony was an engineer with DuPont, working in diverse areas such as fluoropolymers, refrigerants, inkjet and automotive coatings. He has degrees in Chemical Engineering and an MBA.