Calcium casein

Lime casein is a very durable wall technique.
Once dry, it is indelible and resistant to moisture.
However, it is sensitive to low temperatures (-20oC). It then forms a fine network of cracks on the surface of the painting.
In mild climates it can be used outdoors (more durable than fresco).
We prime the plaster under the lime casein with skimmed milk diluted with water in a ratio of 1 : 1.
To prepare the binder, we take skimmed and very fresh curd and add lime cake to it in a ratio of 1 : 2 or 1 : 3.
The lime dissolves the curd, a slightly cream-colored glue solution is produced on the surface.
This binder is diluted with water. It can be used within six hours.
Lime casein should be prepared daily from fresh curd.Curd is an excellent medium for microorganisms. Wanting to store it until the next day, it should be sprinkled with spirit. However, it is best to use fresh every day.
Anti-rot agents, such as formalin or phenol, must not be used.
After drying, lime casein does not have the ability to rot.
To be sure and make it more resistant to moisture, you can spray a 5% formalin solution on the surface of the painting.