Conversion Coatings
For Metal Substrates
● Patent No. U.S. 6,500,276
Polymetalate and heteropolymetalate
conversion coatings for metal substrates
have been patented by
Lynntech Coatings Ltd., College
Station, TX. The conversion coating
solution contains polymetalates
and/or heteropolymetalates to oxidize
the surface of various metal substrates.
The polymetalates have the
general formula M.sub.x
O.sub.y.sup.n-, where M is selected
from the group comprising Mo, V and
W. The heteropolymetalates have the
general formula BM.sub.x
O.sub.y.sup.n-, where B is a heteroatom
selected from P, Si, Ce, Mn or
Co, and M is again selected from Mo,
V, W or combinations thereof. The concentration
of polymetalates and/or
heteropolymetalates anions is preferably
between about one percent and
about five percent by weight. The
patent information includes examples
of typical anions used.