Vacuum Metallizing
"Elvacite" acrylic resins are useful as base
coats and topcoats for vacuum metallized plastics. Low viscosity grades such
as "Elvacite" 2008 and 2013 are effective as smooth, adherent base
coats. They can be applied at high solids, release solvent rapidly, and have
good flow properties to insure hiding of minor surface flaws and scratches.
As in other plastic-coating applications, proper choice of a solvent system
is important in order to avoid crazing of the substrate. "Elvacite"
2008 methyl methacrylate resin requires a stronger solvent system for application
than "Elvacite" 2013 but is more resistant to solvent attack during
topcoating of the metallic deposit.
"Elvacite" 2045 and 2046 butyl methacrylate
resins are suggested for use as clear, high-gloss, scuff-resistant topcoatings
since they can be applied from weak solvents such as VM & p naphtha to minimize
attack on the base coat. Harder coatings can be obtained using "Elvacite"
2043 and 2028 which can be applied
from alcohol-rich solvent systems.
Formula 17 Barrier Coating for Polystyrene Based on "Elvacite" 2013 |
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Ingredients |
% by Wt |
Binder, % by Wt |
"Elvacite" 2013 or 2614 |
18.46 |
100.00 |
Spray solvent for "Elvacite" 2013
(see page 25) |
73.85 |
|
"Ti-Pure" R-900 titanium dioxide1* |
6.59 |
- |
Yellow iron oxide, LL, YLO-178826 |
1.10 |
- |
Total |
100.00 |
100.00 |
Pigment volume concentration, % |
10.5 |
|
Nonvolatiles (solids), % by weight |
26.2 |
|
% by volume |
16.0 |
|
Preparation -Dissolve "Elvacite" 2013 in solvent
blend. Add pigments and disperse in pebble mill or sand mill. |
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Formula 18 Barrier Coating for Polystyrene Based on "Elvacite" 2008 |
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Ingredients |
% by Wt |
Binder , % by Wt |
"Elvacite" 2008 |
9.23 |
50.00 |
Alcohol soluble butyrate5 |
9.23 |
50.00 |
Spray solvent for "Elvacite" 2008
(page 26) |
73.85 |
- |
"Ti-Pure" R-900 titanium dioxide1 |
6.59 |
- |
Yellow iron oxide, LL, YLO-178826 |
1.10 |
- |
Total |
100.00 |
100.00 |
Pigment volume concentration, % |
10.7 |
|
Nonvolatiles (solids), % by weight |
26.2 |
|
% by volume |
16.1 |
|
Preparation -Dissolve "Elvacite" 2008 in half
of the prescribed solvent blend; dissolve alcohol-soluble butyrate
in remaining |
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Formula 19 Abrasion-Resistant Spray Lacquer for Plastics |
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Ingredients |
% by Wt |
Binder , % by Wt |
"Elvacite" 2041 |
1.25 |
25.07 |
Methyl ethyl ketone |
11.84 |
- |
Diisobutyl ketone |
5.90 |
- |
Methyl isobutyl ketone |
11.78 |
- |
"Bakelite" VYHH vinyl chloride-acetate
resin2* |
3.73 |
74.93 |
Acetone |
11.82 |
- |
Xylene |
17.73 |
- |
Toluene |
35.46 |
- |
"Syloid" 378 silica hydrogel24 |
0.49 |
- |
Total |
100.00 |
100.00 |
Pigment volume concentration, % |
5.6 |
|
Nonvolatiles (solids), % by weight |
5.5 |
|
% by volume |
3.4 |
|
Volatiles, |
|
|
resultant solubility parameter, d |
8.9 |
|
resultant hydrogen bonding index, ? |
4.5 |
|
Typical viscosity, Brookfield, mPa?s (cP) |
7.5 |
|
#4 Ford cup, sec |
10 |
|
Abrasion resistance, weight loss, mga |
|
|
50 cycles |
3.4 |
|
200 cycles |
7.5 |
|
Preparation -Dissolve "Elvacite" 2041 and vinyl
resin in ketone solvents, Disperse silica and dilute with remaining
solvents. |
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a) Tested as 0.8-0.9 mil coating on ABS plastic,
using Taber Abraser with CS-10 wheel and 1000-9 load. |
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