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This report describes the second phase of a full technological
evaluation of a novel drier based on manganese and 2,2-dipyridyl.
The objective was to see if this drier could be used as a
replacement for drier system based on cobalt and lead.
The drier was evaluated in over 30 coatings (primers,
undercoats and topcoats) which were representative of commercial
production in the early 1980's. The initial phase of the
evaluation (described in TR/4/85) showed that the initial
whiteness and yellowness of the paints was in general a little
inferior to that of control paints containing conventional
driers.
The extended testing reported here has shown that the
difference in whiteness and yellowing largely disappear on
exposure and that in cracking, flaking, chalking and gloss
retention, the novel paints were as good as or better than the
controls. Flexibility after ageing of the novel drier-containing
paints was in most cases significantly better than the
conventional. Drier-containing paints. Viscosity stability on
long term storage was similar to the control.
The manganese dipyridyl complex is therefore a promising
single drier for the replacement of cobalt and lead.
Further Information
If you are interested in this, or any other project, please contact Richard Holman.
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