Jackson's :Apprêt Plâtre Acrylique : 1 litre:

A primer of high opacity and an intense white with a good 'tooth'. Suitable for most surfaces including canvas, wood, board, etc. Very flexible and ready for use undiluted. Dries quickly with a matt, slightly textured surface. Suitable for acrylic and oil paintings. No sizing required.

Instructions:
1. Stir contents before use. Thin with water up to 10% when applying to absorbent surfaces.
2. Surface to be primed should be clean and free of loose particles.
3. Do not size ground before application. When final coat is thoroughly dry, a second may be applied. Ready for use after 24 hours.
4. Glossy or smooth surfaces should be slightly roughed to improve adhesion before applying primer.
Avoid exposure to frost and do not apply at temperatures below 5C.