I'd love to know what this campaign was like. Since it was a newspaper ad, the copies are long gone. Did they include a piece of aluminum foil? What was the "rainbow" of which they speak? What are the properties of a rainbow that contribute to an association with freshness?

Did it work? Did sales shoot through the roof, and was the company's prosperity so great it made these cards for distribution to employees as a way of saying "here! have some free stuff."