This week I continued my experiments in ink making with India ink. India ink is an extension of the carbon black inks that I have made in previous experiments. It is traditionally made using soot or lampblack as a pigment and shellac as a binder. Because shellac is more challenging to work with than gum arabic, there were several steps that needed to be taken prior to making the actual ink.
Washing Soda
Shellac is a resin excreted by the lac insect in India and southeast Asia. Whereas gum arabic is naturally soluble in water, shellac is not. Starting from its solid form – yellowish, translucent flakes – it must be dissolved in either alcohol or a water-based alkaline solution. I decided to experiment with both.
In order to make my solution alkaline enough to dissolve the shellac, I opted to use washing soda. Washing soda (sodium carbonate) can be prepared from regular baking soda (sodium bicarbonate) which is easy to obtain. This baking soda was spread in a thin layer in a glass dish, and baked at 400° F (204° C) for two hours. It was stirred periodically, to ensure even heating and to expose the resulting product to air.
After two hours in the oven, the white powder in the dish had taken on a somewhat grainy appearance and strong bitter taste, indicative of the transformation from sodium bicarbonate to the much more alkaline sodium carbonate.
Shellac Solutions
I prepared two different solutions of shellac.
The first combined five grams of shellac flakes with 100 ml of denatured alcohol.1 The shellac flakes readily dissolved, resulting in a clear, yellow-tinged solution which smelled strongly of alcohol.
The second solution combined five grams of shellac flakes, three grams of washing soda, and 100 ml of hot water. This mixture never fully dissolved. It resulted in a dark amber liquid – which smelled strongly resinous, like pine pitch – with pale, gummy clumps sitting on the bottom. It is possible that if left for longer, more of the shellac resin would have dissolved.
After struggling with too much binder in previous Type I ink formulations, I conducted a set of experiments in water to determine which binder worked better and what amount was appropriate.
The alcohol solution was pretty useless. While the alcohol dissolved the shellac readily, as soon as it was combined with water the shellac came back out of solution and formed a milky looking suspension. These tiny droplets of mostly solid shellac didn’t have the desired binding effect for ink.
The water-based solution, on the other hand, worked admirably. It readily dispersed into the rest of the water in the ink, and helped ensure a slow, even flow when writing. After some trial and error, I decided ten drops of this shellac solution to a half ounce of water was about the right consistency to flow smoothly on a glass dip pen – allowing three or four lines to be written before the pen needed to be re-dipped.
India Ink
Now that I had my binder prepared, I was able to start making ink. I used the following formula:
- 10 drops of the solution of shellac and washing soda
- 2 tsp coarsely crushed vine charcoal
- ½ oz water
The charcoal, the shellac, and about 2 ml of water were combined in a mortar and pestle, and brayed continuously for 20 minutes. Towards the end of this time, the remainder of the water was added, bringing to total to a half ounce of finished ink.
As homemade inks go, this was my favorite so far. It flowed smoothly off a glass dip pen, able to write several lines before needing another dip of ink. The concentration of pigment was strong enough that the ink was definitively black, rather than gray. This was the first ink I have made that I could see myself using for writing on a regular basis.
There were only a couple of drawbacks. Because there was so little binder used for the ink, it was neither smudge nor water resistant. I think this could have been counteracted by using more shellac – the primary advantage of shellac over gum arabic is that it dries waterproof – but this would likely have resulted in the same challenges with flow seen in previous experiments.
Learnings
On the whole, I like this as a writing or calligraphy ink, so long as it is not used for things that will see a lot of wear and tear. Its likelihood of smudging makes it somewhat impractical for everyday use. Measuring my binder in drops rather than milliliters results in much better flow on glass pens.
- Primarily ethanol, with some methanol added to prevent consumption. ↩︎
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