Opus Resource Library
Solvent-Free in Nature: Cobra Oils
Opus Resource Library

Artists want to be creative without restrictions and are increasingly aware of their health and the health of our environment. Cobra’s vision is to offer a solution to reduce the use of harmful substances in our market as much as possible in the future.

Water-Mixable Artist Quality Paints

Developed with the idea of a solvent-free studio for artists, Cobra Artist Watermixable Oil Paints allow you the freedom to work anywhere: in the studio or on the mountain-top, without the worry of transporting or breathing harmful solvents, and with the ease of soap and water clean up.

Cobra Artist Oils are compatible with traditional oil paints, too, so you can use them with your current oils, and so long as you maintain a 4:1 ratio of Cobra to traditional oils, they will remain water-mixable. Available in 70 colours, these quality paints offer the highest level of lightfastness – at least 100 years in museum conditions – so you never have to compromise on quality or longevity.

Cobra Mediums

Whether you’re extending your paints or changing their working quality, Cobra offer 4 types of mediums that work in tandem with Cobra Oils.

What is Cobra?

Cobra is an oil paint and like every oil paint it consists of a colouring component (pigment) and a binder (a drying oil: linseed oil). So, Cobra does not contain water, but it can be mixed with water.


How is it possible that oil paint can be mixed with water?

To enable the mixing of oil and water, you need an additive.This is called an emulsifier and it creates a stable mixture of small oil droplets in water.



What are the differences between Cobra water mixable oil colours and other oil colours?

The only difference is that while white spirit or turpentine is needed with traditional oil paint, water can be used with Cobra. Diluting the paint and cleaning your brushes can all be done with water. Water replaces white spirit. This allows you to work without solvents, keeping your work space free of unpleasant solvent odours and harmful solvent vapours.This is healthier for you and for your environment.

Can Cobra be used in the same way as standard oil colours for all painting techniques?

Yes, Cobra water mixable oil colours can be used for all oil painting techniques: painting alla prima (wet-on-wet painting) – Layered painting – Glazing – Impasto painting.


What canvases are used for painting with Cobra?

Universally prepared canvases are the correct choice. These canvases are prepared with several layers of Gesso which makes for a good foundation for many types of paint, as oil colours adhere well to the Gesso layer. Cobra paints can also be used on Oil Papers – these are specially prepared papers with an external layer that prevents oil from penetrating the paper.

Does a painting made with Cobra water mixable oil colours have to be varnished?

Yes, the oxygen uptake and thus the ageing process is slowed down by a final varnish.

At the same time, the final gloss level is determined and the paint is protected from

atmospheric contamination. Varnishing is possible at normal layer thickness after around one year of drying. Cobra has low-odour varnishes in spray cans. Varnishes for traditional oil colours can also be used. Watch the video on the website about varnishing Cobra paintings.


Can I strongly dilute Cobra paint with water and use it to paint in a watercolour manner?

This is possible, provided the following is taken into account. By adding a small amount of paint to water you produce a very thin and transparent paint. If, however, a great deal of water is added, the strongly diluted oil will not provide sufficient protection for the pigments. For a first sketch that is later overpainted with thicker paint or paint thinned with a medium, this is no problem. If a work is painted using only highly diluted paint, it is advisable to add at least 20% Cobra painting medium to the water.

Can I mix traditional oil colours and Cobra water mixable oil colours?

Yes, Cobra water mixable oil colour is an oil paint and can also be thinned with solvents such as white spirit and turpentine. It is then no problem mixing with traditional oil paint. And if you would still like to mix with water, keep the 4:1 ratio for Cobra to traditional oil paint.


Can Cobra be mixed with acrylic colours?

In principle, this is technically possible. However, we strongly advise against it as the long-term effects are unknown.


What is the drying time of Cobra?

What is the drying time and how can I make Cobra colours dry more quickly? The drying time is similar to traditional oil paint. The drying time depends on the conditions under which work is carried out (temperature and light) and on the colour used. For thin layers, it takes 2 to 7 days until the paint is (hand) dry, for other colours it may take up to 1 month for a slightly thicker layer. Cobra Quick Drying Medium 093 is a medium that can be mixed through the paint to reduce the drying time of the Cobra colo