UV/LED lamps for nails

[Fresas con Nata]

Hi!

I was browsing mollonpro dot com and I noticed they have an "UV lamp" and a "LED lamp" (hover on "Products" and look at the end of the list). Now, that looks like apples and oranges, no? UV is a property of the light, while LED is a technology that can be used to emit light. There can be a LED lamp that emits UV light, correct?

For new year's eve I had my nails painted with one of mollonpro's monophase varnishes (no base, no top coat, just a single application) and I totally loved it for its glossy finish and their resistance to the minor daily accidents that usually destroy regular varnishes in a couple of days. However I don't want to fry my fingers by exposing them to UV light too often, so I'm interested in getting a LED lamp... unless it emits UV light after all!

Can anyone shed some (visible) light on this? I'm quite a newb when it comes to these varnishes that require a lamp.

[sarah1972]

You are correct - LED refers to the thing creating the light while UV refers to the color (or technically the wavelength) of the light.

And yes, LED's can produce UV light.

Where is dies get complicated is that UV light is divided in three categories: UV-A, UV-B and UV-C. Common assumption is that B and C could be potentially harmful.

The biggest question now is what kind of UV the LED creates. LED's usually create a very narrow band of light on the spectrum. Unfortunately they don't play pride that information.

The other thing to consider is that hardening time for LED is one minute versus 3 minutes for traditional UV lights.

Overall I would go with LED light.

I would guess that doing nails once is likely to be less harmful than a stroll on the beach in bright sunlight...

[Fresas con Nata]

Well I made the research I should have made in the first place

LED lamps are, indeed, UV, mostly UV-A. It's UV light that cures the gel varnish so it becomes solid. The varnish contains some molecules called photo initiators that do the magic. The fastest photo initiators have a orange-ish tint, which is an issue for the clearer, lighter pigmented colours. For these, different photo initiators have to be used, but these are hardly activated by light frequencies within UV-A.

As you said, LEDs emit a narrower band, totally contained within the UV-A range. It causes smaller times for the varnishes that cure at that frequency range but takes longer for others, especially the lighter colours. The bulbs can live for up to 50k hours and need not be replaced. It makes most sense to get the lamp from the same brand as the varnishes because that reduces the curing time to the minimum.

Non-LED lamps (CFL—compact fluorescent lamp) have a broader frequency range with a less pronounced peak. Takes longer for the gel to cure, but lighter colours are an easier target. The bulbs last for ~10k hours and need replacement after 2-4 months depending on how heavily they are used.