Guide to Masking Fluid

By Winsor and Newton

When you want the freedom to apply broad colour washes across your painting surface but do not want the colour wash to cover key details within a composition then Masking Fluid can help.

Unlike Permanent Masking Medium, which is intermixable with water colours, you apply Art Masking Fluid directly on the paper. It can be applied to white paper or previously coloured areas, and it acts like skin over those areas you want to protect from the colour wash. Once you have finished applying the colour wash you can simply remove the Art Masking Fluid.

There are two types: Art Masking Fluid and Colourless Art Masking Fluid.

Art Masking Fluid has a slight yellow tint making it easier to see where it has been used.
If a softer sized paper is used or there is any risk of yellow staining the paper, Colourless Art Masking Fluid should be used.

Here are some helpful tips to get the best results from using both types.

1. Shake the bottle before use.
2. Do not use on wet or damp paper.
3. Use gelatin surface sized paper, this helps to prevent the fluid from adhering too strongly to the paper.
4. Use old brushes or dip pens to avoid damaging valuable brushes.
5. Wash brushes in soapy water immediately after use.
6. Ensure fluid is dry before applying colour wash.
7. Do not leave fluid on paper for long periods of time.
8. If spilt by accident, wash item immediately in soapy water. Once dry, the latex can only be removed by picking at it or rubbing with an eraser. Unfortunately there are no solvents available.
9. Use Colourless Art Masking Fluid if there is any risk of staining from the pigmented Art Masking Fluid.