Casein & Milk Paint Recipe

Casein

With this type of paint, Casein glue acts as the binder for the pigments. Casein is one of the natural components of milk. It is made from precipitated milk, which is then reconverted into glutinous casein glue with the aid of alkali. Casein is one of the first binders ever used by mankind. Casein can be painted on a variety of surfaces, including wood and plaster. Which ever surface used, it must be a rigid one as casein is too brittle to paint on a flexible surface (such as canvas). Casein is also an emulsifier this allows you to "combine" oil and water. There are two methods of using casein in combination with pigments: Lime-casein and Borax Casein. Of the two, the Borax Casein is easier to use and suitable as an artist grade pigment binder. It is used to make such paints that are commonly known as Distemper colors, but can also be used to make larger quantities of paint for interior wall paint applications.

Casein is natural product and will spoil if kept in a wet state. Store unused casein solution in the refrigerator—this should preserve it for two weeks.

Borax Casein

Ingredients by weight:

2 1/2 oz. (80g) Casein Powder
9 fl. oz. (apr. 250ml) cold water
1 oz. (32g)Crystalline Borax
9 fl. oz. (apr. 250ml) hot water

...by volume

5 Parts of Casein w/ 9 Parts Cold Water
2 Parts Crystalline Borax w/ 9 Parts Hot Water

Directions

1. Soak Casein powder in cold water in a covered container overnight.
2. Dissolve Borax Powder in hot water.
3. Add Borax Solution to the Casein Solution and stir.
4. Hydrolysis will start right away and must be completed before the next step (wait approx. 2 hours until no more swelled casein particles can be seen and the yellowish mass is evenly translucent)
5. Heat the solution in a double boiler until it becomes liquid (140° F).
6. Once the solution has cooled, it will return to a syrupy consistency and is ready to be used as a pigment binder.

As with all water-based media, the chosen pigment has to be wetted first. This is achieved by adding small amounts of water to the dry pigment. Then using a palette knife or spatula, the water is worked into the pigment until it retains a paste consistency. The casein solution is then added TO the color paste sparingly. The casein to pigment ratio can not be described in exact proportions. The amount of pigment varies according to desired opacity. The amount of binder (casein solution) varies according to pigment. Before use, apply small amounts to a piece of cardboard to make sure that there is a sufficient amount of binder. If the pigment comes off after a gentle rubbing, add more casein solution. Once pigment and binder have been combined to desired consistency, the resulting paint can be thinned with water.

Casein Gesso

Ingredients

Casein Glue (see above) 9 Parts
Chalk (Champagne or Bologna) 4 Parts
Zinc White (or Titanium) Pigment 4 Parts

Directions

1. Combine Chalk and Pigment.
2. Slowly add mixture to Casein Glue.
3. Mix until smooth.
4. Strain gesso through cheese cloth to ensure that there are no lumps. (optional)
5. Apply in thin layers to a panel that has been sized with Casein Glue.

Applications

Casein Gesso makes an excellent ground to use for any type of paint; it is particularly good for Casein paints.

Lime Casein

Ingredients

40 Grams of Casein Powder
125cc. Cold Water
33 grams Slaked Lime Putty

Directions

1. Soak Casein Powder in cold water in a covered container overnight.
2. Remove excess water from casein by squeezing the soaked casein through a cloth.
3. Thoroughly mix Casein and Slaked Lime together in a mortar and pestle.
4. To prevent lumps, grind the soaked casein prior to being added to the lime. (optional)
5. Within a minute the hydrolyzation will be complete.
6. Immediately following hydrolyzation, dilute mixture with water to a brushable consistency. The volume of water should not exceed the volume of the casein-lime mixture. This binder is then ready to use with alkali fast (see fresco pigments) pigments.

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