I have read a lot of information regarding when Vanity Fair made the switch from their light blue scripted woven tags to their printed block letter tags. (Photos later)
Many, MANY manufacturers of items (lingerie alike) realize that when advertising, it's a good trick to advertise with the same text your actual items contain. I found that sometime during 1955, Vanity Fair stopped using script advertisement, and started using block text.


I literally have spent hours looking for ads that have pre-1955 script used after 1955, and the block text before 1955. This doesn't necessarily mean that this is when they started using block text tags, but with any other manufacturer I find, this holds true, so why not vanity fair also? This also doesn't mean that they stopped using their woven light blue script tags. Evidence below telling about Du Pont's Antron nylon suggests that "Antron III" Nylon didn't come out until about 1970, and yet there are well documents light blue scripted tags that contain the text "Antron III"
In light of my research, I'm not sure an actual switch in tags was made until around 1970, and instead, the two may have been used together say, on different lines. I imagine it was sometime shortly after 1970 that Vanity Fair's lingerie tags stated including their "VF Corporation" logo, since the made the change to "VF Corporation" in 1969, and most of my post '70 items have it. Sometime between 1980 and 1986, the text in the ads switched back to script. I have also realized it's possible that Vanity Fair never stopped using light blue scripted tags, and merely changed from a woven tag to paper.
