www.paintshow.com.br
18
Agosto 2010
PAINT & PINTURA
light-fastness, and resistance to chemical subs-
tances (such as ethanol, gasoline and cleaning
products), scratch and weathering. “In addition
to the benefits that they provide for end users,
polyisocyanates and polyols are materials which
enable formulators to produce robust paints
with a variety of different properties, from
the most flexible to the hardest coating films,
from matte to high-gloss finishes, with multi-
ple layers, and which
meet the most de-
manding application
and dry coating film
requirements. Thanks
to those properties,
combined with the
ability to be cured
at room tempera-
ture or as much as
140ºC, polyurethane
coatings are present
virtually everywhere:
wood coatings (floo-
ring and furniture);
automobiles, inclu-
ding OEM finish, refi-
nish and auto parts;
consumer electronics;
anticorrosive coatin-
gs; home appliances;
and even shoe soles,”
says Alberto Hasses-
sian, head of Bayer
MaterialScience’s
Latin American busi-
ness unit.
Rafael de Moraes Santos, of Quiminutri’s techni-
cal sales support, explains that polyurethane re-
sins are divided into two groups: low-functiona-
lity resins, which provide greater adhesion and
resilience; and high-functionality resins, which
impart high reactivity and enhanced strength.
Among aliphatic resins, there is a family which
provides higher yellowing resistance, which are
particularly well-suited for applications where
the natural yellowing of resins is unacceptable.
“Such resins have a strong presence in coating
for furniture, which require the very high scra-
tch and abrasion resistance, chemical strength,
high reactivity and good curing performance
that are typical of high-functionality polyure-
thane resins. Printing inks for both plastic and
paper surfaces that tend to be more exposed to
friction contain polyurethane resins for good
adhesion and, espe-
cially, outstanding
flexibility. On subs-
trates of complicated
adhesion characteris-
tics, such as glass and
metals, low-functio-
nality polyurethane
resins are a critical
requirement for
improved adhesion,
and naturally provi-
de good flexibility as
well,” says Santos.
Morais de Castro
- A half century of
quality, safety and
efficiency
Now celebrating
its 50 years of ex-
istence, Morais de
Castro started oper-
ating from a small
office space in the
port region of Salvador, Bahia (Brazil). At that
time, the company was primarily an importer.
As Brazil’s chemical industry was expanded and
gained strength in the course of the 1970’s and
80’s, Morais de Castro diversified its business by
becoming an authorized chemical distributor for
Cia. Nacional de Álcalis, Dow Química, Rhodia,
Oxiteno-Ultraquímica and Peróxidos do Brasil,
among other companies.
Today, Morais de Castro is headquartered in