With the end of World War II came a new era of optimism for America: soldiers were returning home, the economy was booming, and everyone was going to live in houses made of ticky tacky. At the forefront of all of this was an inexpensive miracle material with endless applications—not necessarily new, but improved and now more widely implemented than ever before: plastic. Taken for granted today, plastic was the material of the Jet Age: Inexpensive, durable, and colorful, plastic promised to usher Americans from the desperate, aesthetic sterility of the Depression into a bright new tomorrow. From appliance casings to toys, shopping bags to Tupperware, plastic was finding rapid implementation in everyday life as the building block of tomorrow. It's no wonder, then, that this fascination with plastic led to its' reimplementation in the eyewear industry.
Plastic staged its big comeback in eyewear in 1947, when Shuron Optical introduced Browline glasses. A bridge between eras, browlines were half metal, half plastic, and all American, with the frames' interchangeable parts permitting for complete customization of size and fit; the color dynamics of zyl further permitted customizing the color of the "brow" portion of the frame. The design became a hit, ultimately accounting for 50 percent of all eyeglass frame sales in the 1950s.
Plastic would not share its' fame with metal, though. As the 50s gave way to the 60s, advancements in plastic eyeglass design and construction allowed for manufacturers to offer bigger, bolder, more exciting zyl frames than ever before. The browline, meanwhile, had reached critical mass: it had become so omnipresent as to become oppressive, almost like a uniform for an entire generation. The optically challenged flocked away from browlines and towards zyls, which offered an even greater range of selection in size, shape, and even color: Although black horn-rimmed glasses remain the stereotype of 1950s-60s eyewear, this is largely a misconception created by later generations looking back on black-and-white films and photographs; the eyewear of the late 50s and 60s was every bit as colorful as today, with the selection ranging from tortoiseshell to patterns and colors meant to emulate wood and marble.
As the 60s progressed, America's love affair with plastic frames continued, helped in no small part by celebrity appeal. Buddy Holly's glasses quickly became enmeshed in the American subconscious as iconic of rock and roll, while the influx of Italian and French New Wave films featured sexy, brooding leading men and women who sported chunky, boxlike frames. For those who shied away from pop culture influence, the men and women of the US Armed Forces served as eyewear role models in their own right, as the United States switched from the metal frames which had been standard issue during WWII to zyl frames. (Far from the recently issued brown, square frames colloquially known as "birth control glasses" for their generally unflattering appearance, the military issued glasses of yesteryear were much more stylish and fell along the lines of contemporary fashion).
Taking a cue from the browline's downfall, manufacturers were sure to keep turning out unique new takes on plastic eyewear: Plastic browlines emulated the appearance of browline glasses by having dark brow and bridge portions and transparent lower rims; similarly, "Fades" started dark along the upper portion of the frame and became more translucent. "Crystal" glasses (completely clear frames), an oddity of yesteryear favored by Harry Truman, staged a small comeback in the avant-garde scene, as did their cousins, "smoke" glasses (translucent frames). There was even variability in the types of plastic being used: nylon, though not conducive to the coloration that made zyl frames distinctive, proved to be an exceptionally durable material, proving to be much more pliable and flexible (the Criss Optical company, a large manufacturer of nylon frames, even suggested that soaking one's frames in water would make them even more damage resistant)!
Like much of the US, the world of eyewear went a bit crazy in the 1970s. Massive frame styles that dominated the wearer's face became popular for both men and women; and while metal aviators took on a great deal of popularity, plastic frames still stuck around, albeit in much larger and unwieldy fashions.
However, their advent was not without benefits: the weight of the frames coupled with mostly glass prescription lenses made them extremely heavy, awkward, and uncomfortable to wear. This discomfort became a major selling point for plastic and polycarbonate lenses in the next decade, leading to its widespread adoption by consumers.
Though zyl frames had lost the mass appeal they once held, examples of their staying power could be seen through the course of the next two decades: P3 shaped zyls with keyhole bridges, a style often known as the "Preppy," were a large part of the 80s eyewear scene, in both tortoiseshell patterns (amongst yuppies and businesspeople— both men and women) and white (amongst the New Wave scene). Extremely thin, small-framed zyls were a large part of the late 1990s eyewear scene, but were largely the domain of intellectuals, college students, and artistic types: Similar to what had happened to browline glasses decades earlier, zyls had picked up negative associations—in this case, people's parents.
Plastic frames didn't stay down for long, though. The geek chic/hipster revolution of the 2000s brought big plastic frames back into the public consciousness, while the cultural phenomenon of Mad Men revitalized classic eyeglass styles as part of the still-ongoing retro craze. While the less conservative, chunkier styles will probably not survive another decade, this is not to say that zyls will return to the super-slim versions of the early 2000s or disappear all together; rather, a "middling" can be expected as more conservative yet still 60s inspired frames take a firm root in the market.
Though the future isn't entirely certain, one thing is: Plastic glasses have made their mark on the eyewear industry, and even if they fade away tomorrow, odds are, they'll be back around again.
Special thanks to John Tull, MD, for clarification on the chronology of the application of nylon in the optics industry.