Pigment dispersions

I would like information on some products that the technical
department of Ciba recommended for tinting/coloring epoxies and
other coatings. My question to Ciba was: what would they recommend
to tint two-part epoxies for use as a fill for stain glass losses? I
had tried Ciba's Microlith pigments with limited success--it was
very difficult to dissolve the pigments into the epoxy, in this case
HXTAL. The pigment clumped together. Ciba told me that Microlith was
not a good choice and recommended pigment dispersions called
Tint-Ayd from Daniel Products.

The Daniel catalog describes 10 different dispersion systems which
can be used for coloring aqueous emulsions including acrylics, vinyl
acrylic, vinyl acetate, styrene butadiene, epoxy, polyurethane and
for use with solvent-borne coatings of which there is a very long
list but which includes two component epoxy, polyester, acrylic,
nitrocellulose and oil alkyds. One system looked particularly
interesting from a health standpoint called "NV" for use in no VOC
water-borne systems which uses water as the solvent and based on a
high efficiency acrylic dispersion resin.

Has anyone had experience with these dispersion systems? I would
appreciate generally any comments or suggestions. I am in the
process of requesting samples and will try them out in different
coatings.

Another product that is described in the catalog is called Dapro
Ultraviolet Stabilizers which is described as ultra fine titanium
dioxide dispersions which offer protection to the film and substrate
in clear coatings. The titanium dioxide used is 1/10 the particle
size of pigmentary TiO2 and therefore smaller than the wavelength of
visible light, hence no color. The particles absorb, scatter, and
reflect UV light. According to the catalog, the primary uses for
these products are clear wood coatings, colored transparent wood
finishes and clear coatings from which organic UV absorbers have a
tendency to migrate and sublime. Does anyone know about or have
experience with this product? It looks interesting.

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                  Conservation DistList Instance 12:47
               Distributed: Wednesday, November 25, 1998
                       Message Id: cdl-12-47-009
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