MITRA Forum Question Details

ApproveRejectUn-ApproveThanks Brian! Want to know if it's a good alternative to Titanium, Lead and Zinc and if it's a good pigment for painting best practices

ApproveRejectUn-ApproveZirconium Oxide (ZrO2)
 Colour Index: Pigment White 12 / 77990
 According to some sources (one I have cited below), zirconium dioxide or zircon white, has been completely substituted by titanium dioxide. It is used, with other substances, for the adulteration of titanium dioxide to improve the fastness properties of rutile. However, this was written about pigments used in plastics and may not be true for coatings. It has not found much use in coatings, but rather small use in plastics and greater application in ceramics. Albrecht Müller, Coloring of Plastics: Fundamentals, Colorants, Preparations. p. 68–77.

ApproveRejectUn-ApproveOne more comment about zircon white, it has a refractive index of 2.4, so it has nearly the same R.I. as anatase titanium dioxide (2.55), and greater R.I. than lead white (2.1). so it is a fairly "opaque" pigment. There is very little information about its properties in paint, but rather its use in industrial ceramics. There is one study that I know cites it use as a pigments for spacecraft coatings: "Study of zirconium dioxide white pigment for space environment." Journal of Spacecraft and Rockets, Vol. 9, No. 2 (1972), pp. 103-106.

ApproveRejectUn-ApproveI started using Kremer White two years ago, in egg tempera. At first, I found it a very transparent glazing white, even better than lead white. It is not as bright though. Glazes upon glazes, it built terrific opalescent effects. Originally, I bought 100g, and used it up in 2 years. This year, I bought the whole kilo of it (it's not expensive at all), and started using it. To my horror, every application of this pigment resulted in crackling. Even small additions of it make the paint crack as if it were a very strong siccative. Something is different in this batch; so I contacted Kremer. They said they will contact their manufacturers in Germany and will look into it. They were very surprised by this. They haven't yet given their assessment as to what is happening, but I trust they are looking into it. Too bad, I like the pigment very much. It is possible they have modified the manufacturing methods and this has affected the properties of this pigment.