Difference between revisions of "Lime casein"
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== Description == | == Description == | ||
| − | A paint binder or adhesive prepared by hydrolyzing [http://cameo.mfa.org/materials/fullrecord.asp?name=casein casein] powder in water with [http://cameo.mfa.org/materials/fullrecord.asp?name=lime lime] ([http://cameo.mfa.org/materials/fullrecord.asp?name=calcium | + | A paint binder or adhesive prepared by hydrolyzing [http://cameo.mfa.org/materials/fullrecord.asp?name=casein casein] powder in water with [http://cameo.mfa.org/materials/fullrecord.asp?name=lime lime] ([http://cameo.mfa.org/materials/fullrecord.asp?name=calcium%20oxide calcium oxide]). Lime casein is a clear, viscous solution that dries to form a water-insoluble film. Lime casein has a high pH (9.0-9.9) compared to [http://cameo.mfa.org/materials/fullrecord.asp?name=ammonium%20casein ammonium casein] (8.0-9.0), and [http://cameo.mfa.org/materials/fullrecord.asp?name=borax%20casein borax casein] (7.0-7.8). Lime casein is often used as a ground or size for wall paintings on lime plaster, gypsum plaster and stone. It dries to a brittle, insoluble, matte film. Occasionally a plasticizer, such as [http://cameo.mfa.org/materials/fullrecord.asp?name=glycerol glycerol] or [http://cameo.mfa.org/materials/fullrecord.asp?name=sorbitol sorbitol] and a preservative, such as phenol, are added to the solution. Lime casein is also used as a paint binder. Because of its alkalinity, however, its pigment palette is limited (see fresco pigments). Earlier conservation uses have included lime casein as a consolidant for wall paintings and wall plaster. |
== Synonyms and Related Terms == | == Synonyms and Related Terms == | ||
Revision as of 11:03, 13 June 2013
Description
A paint binder or adhesive prepared by hydrolyzing casein powder in water with lime (calcium oxide). Lime casein is a clear, viscous solution that dries to form a water-insoluble film. Lime casein has a high pH (9.0-9.9) compared to ammonium casein (8.0-9.0), and borax casein (7.0-7.8). Lime casein is often used as a ground or size for wall paintings on lime plaster, gypsum plaster and stone. It dries to a brittle, insoluble, matte film. Occasionally a plasticizer, such as glycerol or sorbitol and a preservative, such as phenol, are added to the solution. Lime casein is also used as a paint binder. Because of its alkalinity, however, its pigment palette is limited (see fresco pigments). Earlier conservation uses have included lime casein as a consolidant for wall paintings and wall plaster.
Synonyms and Related Terms
caseinato de calcio (Esp.); lime-casein; casein adhesive; casein glue; calcium caesinate
Hazards and Safety
Casein is susceptible to biodeterioration, especially in humid environments.
Additional Information
H.K.Salzberg, "Casein Glues and Adhesives" in Handbook of Adhesives, I.Skeist (ed.), Van Nostrand Reinhold, New York, 1977, p.158-171. K.Wehlte, The Materials and Techniques of Painting, Van Nostrand Reinhold Co., New York, 1975.
Authority
- Kurt Wehlte, Kurt Wehlte, The Materials and Techniques of Painting, Van Nostrand Reinhold Co., New York, 1975
- Irving Skeist, Irving Skeist, Handbook of Adhesives, Van Nostrand Reinhold Company, New York, 1977
- Website address 1, Website address 1 Comment: http://www.jcms.ucl.ac.uk/issue5/cons98.html#farmakalidis