Grounds offer a white, non-yellowing layer that will afford the painting maximum luminosity. Furthermore, oil paints become more transparent as they age and will show an increasing amount of what is underneath the paint film. Since some sizes and supports can yellow or darken with age, and thus affect the color of the aging painting, priming will help preserve the brightness of the paint.
The application of a ground is also a structural element. This will give sufficient "tooth" for all subsequent layers of paint to adhere to. This foundation will ensure that a good mechanical bond occurs between the support and the paint. Also, if the support deteriorates over time, an isolated paint film can be stabilized more easily. Paintings done directly on the support are much more difficult to repair.
Types of Grounds for Pigment Sticks®
Grounds can be separated into two different categories, absorbent and non-absorbent.
Some grounds are suitable for rigid supports only, because they are too brittle for use on flexible supports. These grounds will be denoted with an (R).
Properties of Absorbent Grounds:
- The paint film will be more matte and softer in tone.
- There will be less undertone and luminosity, making smooth opaque layers easier to achieve.
- The drying process will be expedited.
- WATCH OUT: If too absorbent, “chalking” may occur.
Examples of Absorbent Grounds:
- Acrylic gesso
- Traditional rabbit-skin glue gesso
- Clayboard (support & ground)
Properties of Non-Absorbent Grounds:
- The paint film will be more glossy.
- There will be more undertone and luminosity.
- The drying process will extended.
- WATCH OUT: If too non-absorbent, the paint film may not adhere well and may flake off.
Examples of Non-Absorbent Grounds:
- Oil ground
- Wax ground
- Clay-coated paper (support & ground)