Review on Elmer&#39 Novelty & Gag Toys by Marcus Freeman

Glue that changes color in the sun. I tested the yellow-red variety. The adhesive is yellow at first and dries to a yellowish transparency when applied, but will quickly turn red when wet or dry and exposed to sunlight. Remove it from sunlight and it will gradually turn yellow again. Of course, if you used it to glue, you won't see any color at all and it doesn't matter, so the color changing feature is only useful for slime or drawing/drawing/writing with glue. Aside from the color change, the glue works the same as the standard Elmer washable white glue. The color change appears to occur in response to long-wavelength UV radiation, so some light sources other than the sun also cause a yellow-to-red transition.