A lot of cheap sunglasses brands and dropshipping companies use lenses made from TAC (Triacetate Cellulose). While they may seem like a good deal, here’s why you should avoid them.
What are TAC lenses, and Why are they a Problem?
Triacetate Cellulose is a chemical compound made from cellulose and acetate esters. It’s commonly used for fibers, films, and membranes—but as a lens material, it’s essentially a cheap, clear plastic base.
No inherent UV protection – A UV-blocking filter must be added.
Mediocre optical clarity – Around Abbe 38, which is better than polycarbonate but worse than any other lens material.
Poor durability – TAC is not particularly impact or scratch-resistant.
What TAC can do well is hold laminated coatings—which is why you’ll often see TAC lenses marketed as "multi-layered polarized composite." But this is misleading: it has to be multi-layered because, on its own, TAC is useless.
TAC lenses:
Can have polarized filters and scratch-resistant coatings added.
Are not inherently polarized—a polarized film must be laminated on.
Are not inherently UV protective—a UV filter must be applied.
Require a tint coating, scratch coating, and other layers just to function.
This kind of information is wrong and misleading:
Durability Issues
TAC lenses have major flaws that make them a poor choice for long-term use:
They delaminate over time, especially with exposure to heat, humidity, and sweat.
The polarization film can peel off, making them unreliable.
They are brittle compared to CR-39, Trivex, or polycarbonate, making them more prone to cracking.
Coating wear degrades optical clarity, leading to inconsistent glare reduction.
Some cheap TAC lenses don’t even provide real UV protection—just dark tinting, which is dangerous because it dilates pupils without actually blocking harmful UV rays. Are you going to get $20 sunglasses tested for UV protection?
Why Are They So Cheap?
TAC lenses are cheap because they’re easy to produce. The material is derived from cellulose (from wood pulp or cotton), which is abundant and inexpensive to process. Compared to polycarbonate or CR-39, TAC lenses require fewer production steps and less advanced technology.
That’s why no serious brand uses TAC when better materials like CR-39 or polycarbonate are available. If a brand is marketing TAC as a premium material, it’s a red flag. At best, TAC makes sense for sunglasses under $20—but even then, polycarbonate is preferable.
None of the brands we review at Sunglass Science use TAC lenses. Do yourself a favor and get a pair of sunglasses made from premium materials, with proper construction, that you will enjoy and will last you for many years.