Our display cases are meant to help you display and protect your cherished memorabilia. This means protecting them from damage that dust, fingerprints, spills or ultraviolet (UV) light can cause. From time to time customers ask us about the UV protection our display cases offer. So, we thought a short article on the subject might be helpful.
While a large portion of the sun's rays are visible light, ultraviolet light outside the visible spectrum shoots down alongside it, and these UV rays can have damaging effects on your memorabilia if they come in contact with it, unobstructed, at the right angle. This harmful UV light comes down in three different levels of strength, based on the wavelength, known as short wave, medium wave, and long wave.
Shortwave (UVC's) bands are very dangerous to humans, but thankfully most of these waves absorbed into the ozone as the sun's rays travel down through it to us. Medium wave (UVB) bands make their way down to us and fizzle out on the surface of our skin, but have a hand in sun burns and skin cancer. Longwave bands (UVA) pierce into our skin and cause premature again and wrinkling.
The main difference between these three types of UV light is the wavelength, or the distance between the peaks of each wave in the ray, measured in nanometers. UVC's have a wavelength of 100-280 nanometers; UVB's run from 280 nm to 315 nm; and, UVA's have a wavelength of 315 to 400 nm. The rays that are most damaging to your collectibles have a wavelength of 285 to 400 nanometers.
Many sellers of Acrylic display cases claim their acrylic blocks a certain percentage of ultraviolet (UV) light. You will see numbers like 95% or 98%. We don't give a percentage number since we think that's not the most accurate way to explain it.
Rather, the acrylic we use provides protection from some light waves but other (especially higher spectrum rays) not at all. That means certain light waves are blocked, but not all light waves.
Our cases are designed for indoor use and normal indoor lighting. The acrylic we use is bright and clear. It is great for display and protecting from dust, spills, handling, etc. But it may NOT be effective in blocking UV rays outdoors or direct sunlight through a window. Even indoors, it will not block all UV rays.
Still, our cases do provide significant filtering from some UV rays as you can see from the below images a customer was nice enough to send in.
The photos above show the UV sensitive rock outside the case glows under UV light (from a Convoy C8 UV flashlight). However when the rock is placed inside the case and the UV light shines through the case, the rock it doesn't glow. This is because the UV light from the flashlight gets reflected off the acrylic case and does not penetrate through the case due to our UV filtering acrylic.
The bottom line is the acrylic we use provides good UV protection but we can't guarantee any particular level of protection.
There is such a thing as "museum grade" UV protection acrylic (OP-3) which is much more expensive, and can make the acrylic slightly dimmer, but does provide more protection (though still not 100%). We do not offer display cases made of museum grade acrylic. Again, it is MUCH more expensive.
Please note that if you find another company claiming to offer acrylic display cases with extensive UV protection (98% etc) -- their prices should be at least double our prices. If their price is similar to ours, than it is unlikely their acrylic really offers the UV protection they are leading you to believe it offers.
If you want to do a little of your own reading on UV light's effect on collectibles, you can get started here, or check out some general info on ultraviolet light on Wikipedia. If you have any questions feel free to contact us.