[alfa] Re: Alfa paint AR 119

[Sonny <maxid@xxxxxxxxxxxxxx>]

Matching a historical paint shade could be done by mixing the pigments used in the original paint in the same proportions as John H. suggests, but I don't believe one can find a shop able to do this. 

My painter (who, incidentally, uses the AKZO Nobel/Sikkens system), told me that the base colors are changed by the paint manufacturers on a regular basis due to advances in chemical sciences and tightened regulations. About my 164, he told me that I had been painted with a lacquer based paint, which is no longer used (due to VOC [volatile organic compounds] rules). Also, pigments are now 100% synthetic as opposed to lamp black and what else was used in the old days. I guess I should explain at this point to those who may have missed it that the painter uses only a few base colors to make all the colors of the rainbow.

With the ever changing stock of base pigments, the painters who use a given system (Sikkens, PPG, Dupont, etc.) get new formulas on a regular basis. My painter has his system electronically updated every few months. As far as my 164, the formula was changed recently, probably due to the discontinuation of some base color.

If the painter does not have a given color, then he will use a spectrophotometer to "read" the color and download the information into his computer which will prescribe the right blend of the base colors of the day.

Although the color can be matched, the use of entirely different components than the original paint may produce subtle differences in sheen, "flopping" (i.e. changes in hue depending on viewing angle), how quickly the color fades, and what color it gets as it fades.

A few months ago, I found an interesting tutorial about automotive paint on the net. I believe it was written by one of the big three (Sikkens, PPG, Dupont).

Sonny
164 S
Baltimore
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