EMS has been marketing Primid as a cross linker for powder coatings since 1990. Free from isocyanates, Primid has a clean toxicological profile in respect to occupational exposure, the environment and regulatory compliance.
EMS has been marketing Primid as a cross linker for powder coatings since 1990. Free from isocyanates, Primid has a clean toxicological profile in respect to occupational exposure, the environment and regulatory compliance.
Primid has gained an excellent reputation as a cross linker in polyester powder coatings, in particular for weathering resistant coatings. The cross linking ability of Primid in powder coatings is related to the reaction of Primid's hydroxyl-functionality with the carboxyl-functionality of the polyester resin. However, Primid is readily soluble in water making it an ideal candidate for waterborne systems. It has been positively tested, showing excellent cross linking ability with carboxyl-functionality in waterborne binders such as acrylics and polyesters.
In addition to its use for powder coatings, Primid is now considered as a cross linker in waterborne coatings, for example, in industrial stoving enamels and metal packaging coatings. Typical curing conditions are in the range of 10 minutes at 170°C. However, at temperatures above 200°C curing times can be reduced to just a few minutes. The benefits of Primid in waterborne coatings are VOC reduction, no formaldehyde release and BPA/BADGE-free coatings.
