I used to think that lead white dries quickly in oil and promotes drying when it is a component of mixtures. It’s true that lead white dries faster than titanium white, which is a slow drier, but it is really just normal in overall drying speed.
This has been illustrated for me this week. The background of the painting I’m working on is a gradation of mostly lead white to lead white with a fair bit of raw umber. Raw umber dries quickly and promotes drying when it is a component of any mixture. Over the course of several days, I’ve observed the painting dry progressively from one edge to the other—the more raw umber, the faster the drying. The lead white part of the painting has not dried quickly at all.
Modern lead whites are made with a pigment called “basic lead carbonate.” Historically, lead whites were less pure. They contained basic lead carbonate, as well as other lead compounds that do dry fairly quickly. So older lead whites, such as those made using the traditional stack process, would likely act as driers. It may be that if you bought some stack process lead white from Natural Pigments and mulled it with oil, you’d have a fast drying white.
Other than that, you can make lead white dry more quickly by adding a small amount of lead napthenate or other drier, just as with any other oil paint. Or you can mix in some umber.
Another variable, that you may have omitted, is the vehicle of lead white. Nearly all the commercial lead whites I’ve come across other than the Williamsburg lead white has poppy or safflower oil (slow driers) instead of linseed (fast drier). Even the Doak lead whites would have some walnut oil. If you mulled basic lead carbonate (stack process or modern) in linseed you’d notice a difference in the drying rate.
Brian,
That’s certainly a valid consideration. I’ve used Williamsburg flake (as well as Studio Products flake). They are both ground in linseed oil and appear to be average driers. If you mix a small amount of Doak raw umber with a small amount of Doak flake white, it dries much faster than plain Doak flake white. That suggests to me that flake does not have the siccative properties that umbers have.
This is hardly a controlled experiment on my part; simply an observation.
The reason why so many authors in the past considered lead white to have drying properties in oil is that lead white (basic lead carbonate) has one of the lowest oil absorption numbers of any pigment. Less oil for an equal volume of paint when compared to other pigments makes it a faster dryer than most. However, when you consider that most modern flake white oil colors contain stearates that increase the oil absorption rate of pigments, then lead white is certainly an average drying color.
The reason why so many authors in the past considered lead white to have drying properties in oil is that lead white (basic lead carbonate) has one of the lowest oil absorption numbers of any pigment. Less oil for an equal volume of paint when compared to other pigments makes it a faster dryer than most. However, when you consider that most modern flake white oil colors contain stearates that increase the oil absorption rate of pigments, then lead white is certainly an average drying color.
The reason why so many authors in the past considered lead white to have drying properties in oil is that lead white (basic lead carbonate) has one of the lowest oil absorption numbers of any pigment. Less oil for an equal volume of paint when compared to other pigments makes it a faster dryer than most. However, when you consider that most modern flake white oil colors contain stearates that increase the oil absorption rate of pigments, then lead white is certainly an average drying color.
The reason why so many authors in the past considered lead white to have drying properties in oil is that lead white (basic lead carbonate) has one of the lowest oil absorption numbers of any pigment. Less oil for an equal volume of paint when compared to other pigments makes it a faster dryer than most. However, when you consider that most modern flake white oil colors contain stearates that increase the oil absorption rate of pigments, then lead white is certainly an average drying color.
I appreciate your vast expertise, George. Next time I need more lead white, I’ll buy some from you.
*For readers not familiar with Mr. O’Hanlon, he is the proprietor of the excellent http://www.naturalpigments.com web site. Check it out if you haven’t already.
Hi, I am fairly new to oil painting. I am having a problem with my darks. I like to have really rich, deep darks, but they are drying considerably lighter than I want and a little chalky. Do you know of a way to fix this? Is there something I should be adding to my medium? I use a basic OMS/linseed oil medium.
Thanks,
MT
Matt,
It depends to some degree on which paints you’re using. I myself think it’s better to get fewer paint colors of higher quality than more paints of lower quality.
You may also be getting some “sinking in.” That means that different pigments, which have different amounts of oil, dry to different degrees of gloss. You can fix that when the painting is done using varnish.
old holland-scheveningen has a great lead white, very stiff and fast drier. Also Michael Hardings cremnitz white is great. Dry in two days, and more buttery than Old Holland. These two products are really fine. Rembrandt and Velazquez mixed some egg yolk with it to make it more stiff and structural. I prefer to use cobalt blue as a drier above umber, because it makes mixed tones softer/cooler.
Hey David, Nice painting blog, sure appreciate your little skits on canvas primers. Yah, I will admit that today people are sh-mucked with so called acrylic gessos. What i’ve been doing is taking a basic cotton canvas making sure it’s not to cheap..:).. and then applying some flake white with a little liquin. To my surprise it dries to a nice shiny surface and usually within 2 days. If people only knew the difference between painting on natural primer than acrylic rubber.
Albert,
I’m not a big fan of alkyd mediums myself. If it’s working for you, then great.
basic Lead Carbonate is, in fact, a fast drier. Lead is a siccative chemical, making the the oil dry faster and the lead also create a more flexible film, improving the long term qualities of the finished painting. All but a few paint manufacturers adulterate their paints in some manner to modify the paints they are creating. In the case of basic lead carbonate, manufacturer often add titanium (to brighten the white and increase opacity without increasing the pigment density of the lead) which dilutes the fast drying properties of the lead. Some add Zinc, which varies the particle size of the paint, making the mechanically ground lead “act” like flake white, the consistency of which should be accomplished by variable particle size of lead, which doesn’t happen in most mechanical grinding. Moreso, zinc is a well known anti-siccative pigment. Still others, in an effort to bring consistency to the drying times of their various paints, will add driers and retarders to their paints. And, as has been pointed out, still other companies use poppyseed, safflower, or walnut oils instead of, or added to the linseed to reduce linseed’s natural yellowing but which also slows the drying times of the oil. And lasting, with very very few exceptions, almost all of the paint manufacturers add a great deal more oil than the pigment OA rate. More oil means more drying time AND the less lead there is to impart its siccative qualities on.