BINDERS FOR AQUEOUS PIGMENT PASTES - A NEW WAY FOR THE ECONOMIC MANUFACTURING OF PIGMENT CONCENTRATES

摘要

The first development of a universal grinding resin for aqueous pigment pastes opens up new opportunities for the economic and efficient use of waterborne industrial coatings. The advantages of solventborne pigment concentrates can be fully transformed into the waterborne systems giving all the typical application properties. The low content of butyl glycol is not a drawback for this segment. Butyl glycol is used in most aqueous formulations to achieve better compatibility of the ingredients, to assist the film forming mechanism and to reach the surface flow and gloss of the paint. During the storage of pigment concentrates butyl glycol decreases the tendency to dry out and reflocculate. However, for certain applications the use of solvents like butyl glycol is prohibitive. If other solvents are introduced e.g. via the binder, the overall content of organic solvents may be higher than tolerable. The butyl glycol content also restricts the freedom for the formulator to chose whatever solvent he wants to achieve other properties. Further more, a true Zero VOC paint is not possible. Current R&D work therefore is targeting to develop a solvent-free modification of Laropal LR 8991. This would give more variation possibilities to the formulator and for the application of aqueous pastes. Also the market for architectural coatings would be accessible, a market of high volume, which opens up additional potential for the use of grinding resins in aqueous paints. The first lab examples of a solvent-free modification have been synthesized and have shown the feasability to achieve this goal; the technical availability is expected within the next months.