Excellent scratch resistance is a highly desirable property of Automotive topcoats. As clearcoat appearance of premium car brands in particular become better and better, the difference between a brand new car and a car that has been on the road for a couple of months becomes bigger. As a result, customer complaints about premature appearance loss are increasing.
Wet scratch resistance (car wash resistance) can be improved by adapting the design of the car wash brushes and replacing them more frequently, but this is not sufficient. The polymer design of the clearcoat resins needs to be optimized. Very good results are obtained with clearcoats having increased flexibility. This allows for reflow when the car is standing in the sun, thus “automatically” repairing small scratches. Unfortunately, this does not work for all types of scratches. Specifically, scratches with sharp edges formed due to brittle fracture of the polymer matrix will not easily reflow. The best solution is to prevent these scratches from being formed. This can be done by fortifying the polymer matrix with very hard particles. Of course, the particles should be small enough to make them invisible in a clearcoat. Clearcoats containing hard nano particles have been on the market for quite some time. Allnex now introduces Modaflow NSR 100, a novel very versatile nano silica additive that can be used to improve wet and dry scratch resistance of many different coating types. It also helps to improve chemical resistance and provides easy-to-clean properties to a coating system. In contrast to some of the nano additives available already on the market Modaflow NSR 100 does not negatively affect clearcoat appearance. Although this new nano additive improves scratch resistance of many different coating types, it proved to work exceptionally well in the SETALUX® FC product range of fast drying acrylic polyols.
Hans Schellekens started his career in the coating industry in 1987 when he joined Akzo Nobel Resins in Bergen op Zoom, the Netherlands. He became responsible for the development of acrylic resins for application in the automotive OEM and Vehicle Refinish market. Later on he was appointed Product Development Manager for Automotive OEM. In this role he contributed to the development of new products for waterborne and solventborne primers, basecoats and clearcoats. Since 2005 he also provided technical support to customers, first in South-America and later to customers in Japan, Korea and China. In 2017, upon the merger of Allnex and Nuplex Resins, Hans was appointed Global Marketing Manager for Automotive OEM and Vehicle Refinishes for the Liquid Resins and Additives business unit (LRA).