[alfa] Pastello

["John Hertzman" <johnhertzman@xxxxxxxxxxxxx>]

I want to thank Luca for adding immeasurably to the paint discussion, but I must question something he says about metallics ("The metalized color are typically mat, so the 2nd transparent layer is very imporant to give it the brightness") and to a lesser extent one of his comments on 'pastello': ("This leads to the conclusion that a 2nd layer for PASTEL COLOR must be there for a matter of quality and resistance. It doesn't need it, it look fine alone, but it could be too weak for a car (bugs, rain, sun, parking outside, salt, winters....").
 
The Alfa Body Shop Manual #1570, for Giulia and 1750 tintops (published in 1970) says:
"The cars manufactured by Alfa Romeo are finished either with synthetic enamel or with thermoplastic acrylic lacquer, specifically:
"a  PASTEL COLOUR FINISH
"Synthetic enamel (oven drying at 140 C)
"b  METALLIC FINISH
"Thermoplastic acrylic lacquer (oven drying at 140 C)"
 
It continues with the use of the same materials in repairs both dried at 80 C or the lacquer dried at ambient temperature for 24 hours. At that date neither was clear-coated, metallics were invariably lacquers, and all nonmetallics were synthetic enamels evidently called "Pastel" by Alfa with no reference to gloss or paleness.
 
Most of the handbooks published by paint manufacturers avoid discussion of the chronology of paint materials. DuPont is an exception; they developed enough of the materials to brag on the firm dates of some innovations and to speak more generally about evolving technology when they were not the innovators. They write of materials they developed and introduced in 1982 in response to "the ever increasing number of cars on the road with a Base/Clear finish either from Europe, Japan or the United States". It seems a fairly safe bet that production clear-coats were first used in the late seventies on premium European cars.
 
In my experience the acrylic lacquers used by Alfa in the seventies were relatively short lived, but the solid color synthetic enamels were extremely durable. The later clear coat systems were certainly more brilliant, and in the metallics more durable, but some find them as much of an anachronism on a vintage Alfa as any geewhizz radio head.
 
Enough. Enjoy yours,
 
John H.
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