Product Information Sheet

GOLDEN Phosphorescent Green (previously known as Phosphorescent Medium) is a non-hazardous, waterborne acrylic polymer medium that is formulated to emit a yellow-green glow after being properly charged with a light source.


Golden Artist Colors, Inc.
188 Bell Road
New Berlin, NY 13411-9527 USA
Toll Free: 800-959-6543
Fax: 607-847-6767

GOLDEN Phosphorescent Green is a water-based acrylic medium that can be applied to various surfaces. The unique pigment used in its formulation is characterized by its ability to absorb and store natural and artificial light. When the light source is removed (i.e.: when the lights are turned off or the painted object is taken into a dark area), a bright, greenish glow is emitted for up to 15 minutes. The glow steadily diminishes as the stored light energy is released.


GOLDEN Phosphorescent Green can be brush-applied in the same manner as other acrylic paints. However, there are certain guidelines the artist must follow to maximize the intensity and duration of the glow. The glow time is directly related to the thickness of the applied medium, as well as the intensity, quality and time of exposure to the light source.

Film Thickness
Thin coats of Phosphorescent Medium will not produce a long-lasting, glowing effect. In order to maximize the effect, apply several layers of the medium until maximum opacity1 is achieved.

To test the effectiveness of each coating, and to later test which available light source works best, make a test panel where layers of the medium are built up.


  1. Begin by applying an even coating to a piece of illustration board or other suitable substrate. Allow to dry.
  2. Leave a section (1/10th of overall board) with just one coat, and apply the next coat. Allow to dry.
  3. Repeat this step until several coats of at least 5 different thicknesses are built up to produce an opaque coating. Allow each layer to fully dry before proceeding. The end result should look like "steps" being built up as each layer is applied.

This test panel will show how many coats are needed to give the maximum glow. The light source is equally important for maximum glow.

Light Source
Natural and artificial light sources can be used to "charge" GOLDEN Phosphorescent Green. Light sources rich in Ultraviolet (UV) are most effective. Tungsten and Fluorescent lights will work, but some sources can take longer than others depending on their intensity (wattage). The fastest charge can result from a good Ultraviolet Light, commonly referred to as a "black light". The black light will also allow a bright glow to remain constant if left on during viewing. Infrared lights will not charge this product.

Use the test board with the different layers of medium to check which source will work the best for each use. Experiment with different types of light and their proximity to the Phosphorescent Green.

Blending with Other Acrylic Paints
GOLDEN Phosphorescent Green is not a true blending medium like GOLDEN Polymer Medium. Mixing with acrylic paints will substantially diminish the glowing capability of the product. If color is absolutely essential, the Fluorescent Paints diminish the glow the least. They must still be added very sparingly.

Any paints applied over the medium will also inhibit the glow. Even a transparent glaze will interrupt the charging capability of the medium.

Phosphorescent Green can be blended with any of the GOLDEN Gloss Gels or Mediums. Experimenting with different ratios of gel and Phosphorescent Green will produce different appearances. Blending the medium with GOLDEN Gels that are thick, such as Heavy Gel or High Solid Gel, will allow a much thicker, one-coat application.


  • GOLDEN Phosphorescent Green is not Lightfast2, meaning that the more exposure to light it receives, the faster it fades. If an object begins to lose the ability to charge, additional coats may be applied at a later date.
  • Black lights put near the object can keep the glow appearance more constant. Experiment with intensity of light and distance of UV light to the object.
  • An opaque, even coating can be used as a glowing "chalkboard" with the aid of a flashlight. Messages can be "drawn" and the duration depends on how fast or slow the flashlight is moved across the film.
  • To hide the Phosphorescent Green during normal viewing, apply the medium over a base color that is similar in hue and value. This will allow even heavy coatings to be undetectable during normal lighting. Using this technique will allow for "hidden" messages or graphics to be put into an artwork


1Opacity - the degree to which a material obscures a substrate or underlying paint layers.
2Lightfast - ability to withstand color change due to exposure to light.

The above information is based on research and testing done by Golden Artist Colors, Inc., and is provided as a basis for understanding the potential uses of the products mentioned. Due to the numerous variables in methods, materials and conditions of producing art, Golden Artist Colors, Inc. cannot be sure the product will be right for you. Therefore, we urge product users to test each application to ensure all individual project requirements are met. While we believe the above information is accurate, WE MAKE NO EXPRESS OR IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, and we shall in no event be liable for any damages (indirect, consequential, or otherwise) that may occur as a result of a product application.