Over the years, automotive coatings have evolved from primarily low-solids solvent borne thermoplastic lacquers to thermosetting, waterbome and high-solids systems. The key drivers have been environmental regulations and cost. Conventional lacquer formulations were generally based on resins with a higher molecular weight. They required a significant amount of solvent to achieve the desired application viscosity. However with most countries in the European Union (EU) adopting the volatile organic compound (VOC) paint directive as of January 2007, there is an need to match the performance of traditional coatings with novel, higher solids, VOC compliant formulations. The automotive refinish clearcoat sector is preparing itself for the transition from conventional, low-solid formulations to coating systems that are much lower in volatile organic compounds (VOC). In that, the key challenge is to achieve comparable properties to those of the conventional systems. A new cellulose-based additive can improve the overall performance of VOC-compliant refinish clearcoats. It has been demonstrated that a new additive can serve as a useful performance additive in VOC compliant refinish clearcoats. Incorporation of the additive in the clearcoat resulted in a much faster increase in the complex viscosity when compared to other commercial VOC compliant systems and thus improves anti-sag behaviour. The high T(g) of the material enables it to provide quick dry-to-touch time along with the initial hardness deyelopment and thereby increase the throughput i.e. reduce the time required to process each job at the auto refinish body shops. Polishability studies indicated that addition of the new product to a clearcoat system resulted in rapid improvements in the 200 gloss after polishing. This can result in fewer steps during the polishing operation.
Easier repair. A cellulose-based rheology additive enables high performance VOC compliant car refinish clearcoats
Einfache Reparatur. Ein Cellulose-basierter rheologischer Zusatz erlaubt die Herstellung eines leistungsfähigen, VOC-reduzierten, transparenten Reparaturlacks für Autos
European Coatings Journal ; 12 ; 30-35
2007
6 Seiten, 6 Bilder, 2 Tabellen, 5 Quellen
Article (Journal)
English
Automobilbau , Beschichten , Compliance-Richtlinie , flüchtige organische Verbindung , EU-Richtlinie , Additiv , Cellulose , Reparaturmaterial , Karosserieinstandsetzungssystem , Glanz , Polieren , Glasübergangstemperatur , Viskosität , Trockenzeit , organisches Lösungsmittel , MAK-Wert , transparentes Material
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