20. MASKING FLUID - WHAT IS IT AN HOW IS IT USED?
Masking fluid (sometimes called liquid frisket) is a resist material comprised of latex rubber in a water/ammonia mix. It is used to protect the
dry surface to prevent further washes from reaching the paper and can be used to protect white areas or previous washes. Popular makes are Winsor & Newton (yellow) and Pebeo (blue), and in the US Incredible White Mask and there is a range of special applicators called
Masque Pens which comprise a bottle of masking fluid with a fine metal applicator tube affixed to the cap, allowing direct application to the paper.
When exposed to air masking fluid dries to an impermeable rubber film which lies on the surface of the paper. When you have completed work in the area it is advisable to remove the masking as soon as possible.
On no account should masking fluid be applied to wet paper as it will soak in and be impossible to remove.
Masking fluid is best removed with a special rubber pick-up, but it can simply be rubbed off with your finger.
Due to the rubber content, it is advisable not to use a good brush to apply masking fluid, as it is almost impossible to remove dried masking fluid from the bristles. Any cheap brush or pointed implement can be used and it is best to protect the bristles by rubbing on a bar of soap before dipping into the fluid. Some people use a metal ruling pen as it can be used to draw fine lines or cover larger areas and is easy to clean.
Make sure you replace the cap immediately to prevent drying up in the bottle. masking fluid should be stirred and not shaken a bubbles are difficult to remove. For masking fine lines it can be diluted slightly with water. Masking fluid has a definite shelf life and should be replaced once it becomes thick by evaporation.
Alternative methods of masking larger areas include the use of adhesive frisket or masking film, often used by air brush artists or simply masking the edges the protecting larger areas with paper or Saran wrap. If there is no intention of painting over the masked areas, some people even use clear candle wax or white crayon as a resist for small areas or to apply texture.
Useful Threads:
Using Masking Fluid by juneto
Masking Fine Lines