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dbclemons
08-10-2009, 07:05 PM
Water and Oil Emulsions: Egg

This is a quick demonstration to show how I make a very nice oil medium using an egg. There are several other water and oil emulsifiers, but an egg is the easiest to come by and put together into a medium. For the benefit of this forum Iím using a water-miscible stand oil medium from Winsor & Newton. Any type of oil will work, including regular painting oils, but I find these water-miscibles tend to be more useful in emulsions due to their water compatibility.

The advantage of using an egg/oil medium is the egg will dry very quickly, and if you use this with regular oils (not water-miscible) you get a benefit of a medium that thins with water. Egg is not the fastest drying emulsifier Iíve used, but it will still be faster than if you used an oil medium by itself. As with egg tempera, the egg dries almost immediately, but overpainting with a new oil layer will probably need to wait for a few hours. Bear in mind that the oil will still need to completely dry at its own rate just as always. However, the dried egg will hold the paint and pigment in a sort of suspension (nailing it down, if you will) so that new oil layers will not move it or blend with the new paint you add, at least thatís how I would describe it. Fat over lean rules still apply also, but thereís so little oil in this mixture by volume that I donít see any problem using it in the initial layers as long as the covering layers are not more diluted. The egg also tends to give the paint a short stroke or pull as you work it, so it tends to work best in short brush applications rather than long broad strokes; however, it can be diluted and makes a nice undertone. It also works very well for adding thin details. Youíll need to test it out for yourself to get a proper feel, but itís very easy and fast to make.

http://www.wetcanvas.com/Community/images/10-Aug-2009/5224-egg_oil_medium.jpg

Ingredients and utensils:
1 egg
Oil medium of choice *
Distilled water
Two mixing jars
1 measuring spoon

The egg Iím using here is a ďlargeĒ chicken egg. Some recipes Iíve read for this recommend using the freshest egg possible. The reason being that any air reaching the yolk will start to break down the protein in it that will weaken the binding strength. Personally, Iíve not found the freshness to be all that to be significant. If the egg is good enough to eat, itís fine by me for painting. Your grocery store should have date stamps on the carton or even the egg itself to help judge how fresh it is

ďMedium of choiceĒ means you can use any sort of oil you prefer, linseed, stand oil, walnut, etc.; theyíre all compatible. You can also use a resin varnish as a complete substitute for the oil, or in combination with the oil.

A varnish and egg mixture will dry more quickly than one that includes oil. The varnish can be damar, venice turpentine, canadian balsam, copal, etc. Of course these varnishes use turpentine which some water-miscible painters may object to. Winsor & Newton has a new water soluble varnish on the market, but I donít know what itís made of or how/whether it would work in this fashion, so I wonít recommend it. Saponified (softened) wax is another possibility.

The stainless steel jars I found in the fish section of my supermarket. They were sold for dipping sauces. The glass jar is a baby food jar.

Recipe:
1 egg yolk
1 part oil (or varnish, or oil and varnish mixed)
2 parts water
This makes approximately 2 ounces of medium.

To break the yolk itself into a jar, separate the yolk from the whites and remove the white string membrane thatís attached. Place the yolk on a paper towel and gently dry it off. Carefully hold the yolk ball over the jar and poke it with a sharp knife. The yolk will empty into the jar and you can toss the outer skin. The yolk from this egg equals approximately one tablespoon in volume, but yours may vary.

I poured one tablespoon of oil into the egg. I filled the other jar (they donít have to be steel, by the way) with 2 tablespoons of water, and slowly drizzled the water into the egg and oil while stirring. Less water will make a thicker medium, so test the consistency as you pour it to get it how you want.

Thatís it. Ready to start painting. Youíll need to stir it occasionally to keep it all emulsified. I should add that this medium makes a very serviceable paint in its own right just by adding pigment. As with pure egg tempera, itís advised that you only paint on firm supports with this medium and not stretched canvas. This medium has a slight yellowish tone to it, but itís not very noticeable even on a white ground and mixed with white paint it doesnít change the hue.

How long this mixture will keep is hard to determine exactly. Some say to make it up every day as they would with egg tempera, others say no more than one or two weeks. The egg will still spoil, so at the least Iíd suggest keeping it under refrigeration and then use at room temperature. You could try adding a drop or two of clove oil or white vinegar as a preservative.

If I get some time tonight I'll try to start an oil sketch as an example. Later on I'll add information on using other emulsifiers too.

couturej
08-10-2009, 07:48 PM
Wow David thank you for doing this! I'm pulling up a chair... looking forward to your next post.

karenlee
08-10-2009, 07:53 PM
Very cool, Dave; I've fiddled with egg tempera, so your method looks really interesting!

dbclemons
08-10-2009, 08:29 PM
There's a nice forum here on WC for Casein, Gouache & Egg Tempera (http://www.wetcanvas.com/forums/forumdisplay.php?f=345)for those who don't about it. It's worth checking out.

Casein is another water & oil emulsion (gouache isn't) that I was planning on talking about later. I love using the medium itself for painting. I've not done much with e.t. paint but have often experimented with egg and oil mixtures.

brushstrokebliss
08-11-2009, 12:04 PM
What a fascinating chemistry lesson. I've never heard of using eggs in painting. Thanks for sharing.

Bliss

dbclemons
08-12-2009, 06:34 PM
Here are a few stages of a quick oil sketch based on a recent drawing of mine. These each use an egg/oil mixture as described in the recipe above. The surface is an 8x10" piece of Multimedia Artboard.

http://www.wetcanvas.com/Community/images/12-Aug-2009/5224-eggoil1.jpg
http://www.wetcanvas.com/Community/images/12-Aug-2009/5224-eggoil2.jpg
http://www.wetcanvas.com/Community/images/12-Aug-2009/5224-eggoil3.jpg

I wanted to use a range of brands for the demo, so I started with a layer of Duo Raw Sienna, followed by a drawing made with Max Raw Umber, and lastly an overall rub of Artisan Burnt Sienna. Teh first two stages only need about 30-45 minutes to set, so it was all done in a little over an hour. The final rub of burnt sienna never moved any paint below it. The amount of egg/oil medium added to the paint was about 20% or so by volume.

http://www.wetcanvas.com/Community/images/12-Aug-2009/5224-eggoil4.jpg

After looking at that third stage above I wasn't too fond of the saturated red of the burnt sienna, so I decided to go back over it with more raw sienna. Since the burnt sienna had only partially set, with this last layer I was able to rub through it in some places like the lit areas of the face and brush down into the first raw sienna layer I started with. This was lighter in tone and gave me a nicer neutral soft highlight. I don't think it even needs color at this point. (Note: this last photo is of wet paint that's causing some reflections.)

couturej
08-12-2009, 09:59 PM
This just keeps getting better and better. Still watching and learning. :)

couturej
08-15-2009, 08:31 AM
Hi David! I just realized that you stated it doesn't need color. I agree! Thanks again for taking the time to post this wonderful thread! :)

Ruthie57
08-15-2009, 03:55 PM
Fascinating! Thank you.

dbclemons
08-15-2009, 06:05 PM
Thank you. Here's a more accurate scan of the last stage. I may get back to painting it more later, but for now this shows the process well enough.

http://www.wetcanvas.com/Community/images/15-Aug-2009/5224-eggoil4.jpg

dbclemons
08-16-2009, 09:38 PM
By the way, I thought I'd best quote the source of my information on this, or at least where it started from, so no one thinks I'm making this stuff up. It stems from "The Practice of Tempera Painting" by Daniel Thompson. This is generally regarded as the primier book on the subject and can be read in it's entirety here:
http://www.noteaccess.com/Texts/Thompson/index.htm

The final chapter (8) talks about water and oil emulsions.

dbclemons
08-16-2009, 11:05 PM
Another water and oil emulsion is casein. It's also mentioned in the Daniel Thompson book I linked to above. Like egg yolk, casein is a paint binder that has an ancient history, older than oils. It's the name for milk protein which can be made into a glue.

WetCanvas has a forum devoted to Casein, Gouache, and Egg Tempera (http://www.wetcanvas.com/forums/forumdisplay.php?f=345)where I have posted some articles about how to make your own casein binder (http://www.wetcanvas.com/forums/showthread.php?t=391186). I also have articles about it on my website (http://www.dbclemons.com/articles.htm) that may be more up to date. The simplest way is to buy dry casein powder which is available at several online stores that cater to pigment supply, such as Natural Pigments (http://naturalpigments.com/) or Sinopia (http://www.sinopia.com/). In order to make this into a glue you'll need an alkali catalyst such as ammonia carbonate, or my preference, borax. I've found that the borax I can get at a local grocery store works just fine.

I would recommend using the casein binder in the same proportion as the yolk recipe at the top of this thread, 1 part casein to 1 part oil (and/or varnish) to whatever amount of water you want up to 2 parts.

There are a few differences between the two. Eggs are easy to come by. Casein CAN be extracted fairly easily from milk but it's not as easy as cracking an egg. Casein takes a few hours to gel properly, whereas yolks can be used right away. However, eggs spoil but the casein powder will last indefinetly, and is more economical by volume. Casein is clearer than yolk. The drying times are about the same. Casein can also be used to make a very good gesso ground. All in all, casein or yolks are more or less equal in terms of how they mix with oil. Many of the oils on my website have a casein and oil underpainting.

autolisp
08-26-2009, 06:02 AM
A very interesting post.

David. Have you tried any emulsions using only the 'egg white'?

autolisp

dbclemons
08-26-2009, 10:14 AM
Some recipes include the whole egg instead of just the yolk, but I've only used the yolk. The white contains mostly water and when used by itself needs to be beaten and drained ("glair.") I suspect its use would make a cloudy and more brittle binder.

I have read that egg white glair can be used over a partially dry and sticky oil surface as a sort of varnish that will help keep the surface clean but not harm the painting. Never tried it. It might also discolor but shouldn't be too difficult to remove.

juneandf
10-10-2010, 01:16 AM
David, Thank you so much for your information on Tempera, wow, I am only a beginner but I will certainly try it. What fun!

DaveGhmn
10-11-2010, 04:23 AM
As long as we're at the intersection of artistry and cuisine, has anyone experimented with mustard? The chemistry might mitigate against it, though the emulsification effect can be higher than egg yolk.