I'm using thermal labels as contact information and descriptions on the backs of wood products that I sell. I was thinking, that if I could cover the label, with a clear permanent coating, that it may be legible for several years. For instance, a thermal label on wood, covered with shellac, epoxy or clear spray paint..... Has anyone ever tried anything like this? If so, does it work?
Thermal images fade. They are not archival. Treating them for permanence is an exercise in futility.
Rather than all that ridiculous amount of effort to save a thermal image, my HACK is to make a photocopy (with carbon-based toner) that does not fade.
Better, make the original image using a black/white laser printer so that you have a choice of stable base material to print on. Your choices are paper, card-stock, and plastic. In addition, some materials have adhesive-backing for peel-stick application.
Paper Label HACK: Have you considered using an electric (or manual) Branding Iron for your wood products?
For use on wood or leather, electric branding irons have solid brass heads that can be set with up to 20 characters per line (including spaces and punctuation).
These irons reach over 720°F (382°C) after about 15 minutes. One supplier (search online) offers one model with “HANDCRAFTED BY” as the first line, another with “FABRIQUÉ PAR” as the first line, and a custom model with two lines of your choice. Letters are upper case, 3/16" high. For names such as “MACDONALD”, the “A” and “C” will be upper case, but in a reduced size.
Looks great. Fits your product line appropriately.
I'd use an engraving pen (rotary abrasive kind) and just write your name in for now. You can perhaps create hardwood plinths later that you will 3D router, or look at a low-powered laser engraver that will burn some wording into the wood; it's much more permanent.
If you're after something lifehacky you might find some success with a number and letter punch set (or even bending a design out of metal wire), heating it up and burning a design in by resting wood on the hot object...