Have you ever experienced when the binder and the pigment did not mix well while making your own paints? 

This kind of situation is caused by surface tension, it is often seen with organic pigments such as phthalocyanine and lake pigments, as well as with effect pigments.

Here is what happened when I mixed Gum Arabic and Astroflake 12/Royal Blue #20 on a paper palette.

 

When making water-based paints with pigments that have high surface tension, you can prevent this to happen by adding anhydrous ethanol while gradually applying water to the mixture. 

Although this is one way to do it, we have another easier way.

Adding the Pigment Dispersant for Aqueous Paint released by Kusakabe Corporation lowers the surface tension and pigments that float in water become easily mixable with binders.

 

Pigment Dispersant for Aqueous Paint

 

The following picture shows what the same mixture looks like but it’s mixed with a Pigment Dispersant this time.

As you can see, the pigment now can be mixed a lot easier with the binder after adding just a drop or two of dispersant. And of course, you don’t have to worry that the dispersant will change the color of your mixture. 

Just a few drops of this dispersant will have a powerful effect which is good when you want to make paints efficiently. However, if you want the paint to be blended better on paper that tends to repel or if you want to increase the adherence to the substrates, adding a weaker dispersant would be better. If that’s the case, Ox Gall is what you need.

Z/OX GALL

OX GALL

As the name implies, Ox Gall is extracted from the bile of oxen and cows. Ox bile contains a surfactant that is important for making paints bleed well. Although the term of using surfactant may sound new to some of you, the most common examples you can find in our daily life are dishwashing and laundry detergents, they contain surfactants too.

The surfactant has three main effects: a penetrating effect to soak into fibers, an emulsifying effect that makes oil and water uniform by connecting them, and a dispersing effect that spreads particles throughout the liquid.

Adding the Ox Gall is not only effective for applying paint evenly on a surface, but it can also improve the fixation of sizing (Dosa) to the paper.  

In such cases, we can achieve the same result by applying water-diluted Ox Gall on paper before painting. The appropriate amount is 2 to 5 drops per 250 ml of water. More than 2 to 5 drops may result in poor color saturation and coloring failure.

Here's the result of a comparison of different applications.

【Art Materials Used】

Substrate： Ganpishi Sarashi / Bamboo Washi for Watercolor Art Pad

Color Material： ZECCHI Watercolor

As you can see above, the same paint appears differently on the same substrates simply by adding Ox Gall.

The upper row is painted on Bamboo Washi for Watercolor Art Pad, which some of you may be familiar with since we use it a lot to create samples in our articles. This type of paper is suitable for watercolor painting, so the watercolor can blend in on the paper reasonably well even with just water.

Mixing with Ox Gall, allows the color to be soaked deep into the paper, therefore, the color tone appears darker.

For samples in the lower row, I colored on thin papers called Gampi. It has a glossy and smooth surface, and is more resistant to water than Kozo paper. I could draw strong strokes with only little blotting because I did not add much water to the paint.

And then, when Ox Gall was added to the color, the paint spread out instead of soaking into the paper, so the result came out as a lighter tone. Therefore, adding Ox Gall can control how much paint bleeds on paper.

In addition to these techniques, Ox Gall is very useful when you want to apply water-based colors to paper that easily repels water.

For example, Metal Leaf Paper manufactured by Rekiseisha Co., Ltd. has a coating over metal leaves that may repel watery paints such as transparent watercolor.

Here are the samples from when I tried applying color to the gold and silver scraps of handmade Metal Leaf Paper.

【Art Materials Used】

Substrate： Metal Leaf Paper

Color Material： ZECCHI Watercolor

As you can see in the sample on the right, adding Ox Gall helps the paint to stay on the slippery surface. It also makes the paint not soak into the substrates, so the thicker paint coat remains on the painting surface which can be quite interesting as well.

 

Of course, this technique can also be applied to the case when you want to paint Sumi ink on metal leaves.

Moreover, it makes it possible to paint on substrates that have not been tried before, such as Colored Titanium.

Last but not least, for those who want to make paints using the effect pigments but cannot mix well with binders, or for those who have substrates or materials that the paints just won’t fix on it, I suggest you try using the Pigment Dispersant for Aqueous Paint or Ox Gall.

Translated by Atsumi Okano and Nelson Hor Ee Herng
PIGMENT TOKYO Art Materials Experts