Vinyl top

Vinyl roof refers to a vinyl covering for an automobile's top.

This covering was originally designed to give the appearance of a convertible to models with a fixed roof, but eventually it evolved into a styling statement in its own right. Vinyl roofs were most popular in the American market, and they are considered one of the period hallmarks of 1970s Detroit cars. Vinyl roofs were also very popular on European- (especially UK-) and Japanese-built cars during the 1970s, and tended to be applied to sporting or luxury trim versions of standard saloon (sedan) models

The first use of this technique goes back to the 1920s, when leather, canvas and vinyl were sometimes used along with landau bars, to give a fairly accurate reproduction of a horse-drawn carriage's movable top. An early example of this was the 1928 - 1929 Ford Model "A" Special Coupe, that featured a roof completely covered with a vinyl-like material. This Model "A" Special Coupe's vinyl roof had two exposed seams on the back corners, with a lateral seam on the top covered with a narrow trim strip; landau bars were not provided on this model. The technique fell out of favor in the 1930s and 1940s, when smoother, "envelope" bodies began to be fashionable; for these designs, the look of the modern, integrated metal roof was important.

Lincoln used the convertible look on some of its Cosmopolitan coupes in the 1950s, as did the Kaiser firm on its Manhattan sedans, although the material was still canvas. In the very late-1950s, Chrysler's Imperial made a limited use of true vinyl on some models. Probably the first modern vinyl roof as it would later be accepted, though, was the 1956 Cadillac Eldorado Seville that came standard with a roof covered in an early vinyl material called "Vicodec" with two parallel seams running the length of the roof. Ford followed a few years later with a vinyl roof option on the 1962 Ford Thunderbird, a car which also re-introduced landau bars as a styling touch. The vinyl covering proved popular, and some form of vinyl trim would be seen on Thunderbird roofs for the next two decades.

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Wikipedia