PRODUCT INFORMATION SHEET

Cold pressed walnut oil

Product Description

Natural drying oil used as a traditional binder for grinding oil colours.
Alternative to Linseed Oil with similar drying rate.

Product Code: 039

Constituents: Walnut Oil. Extracted from walnut (Juglans regia) using cold pressing method.

Product Application

Made by crushing ripe walnuts under pressure, it has historically been used as an alternative to linseed oil for making oil paints. Low yield of oil from the seed using this extraction method. Walnut, like all artists’ drying oils, harden by absorbing oxygen. As it oxidises, it also polymerizes at a molecular level being changed into a non-reversable film.

Cold Pressed Walnut Oil has greater wetting power than refined linseed oils and is often recommended for hand milling of oil paints for this reason. In theory, a higher level of pigment can be mixed with cold pressed walnut oil than other oils although factors such as the limited amount of pressure applied in the hand milling process should be taken into consideration. The pressure applied using commercial triple-roll machine mills allows for far greater amounts of pigment to be introduced by an oil paint manufacturer if they so desire.

Used even in small quantities, adds a loose, slippery quality when added to oil colours. The paint film will stay open and is easily moved or reworked for up to 24 hours. Cold Pressed Walnut Oil when used to mill oil colours or even when mixed with prepared oil colours removes the pronounced stroke to the brushmark, so that strokes of different directions and application do not show a marked ‘suede’ effect as often seen with Refined Linseed Oils.

Cold pressed walnut oils have been found by analytical scientists to create a softer paint film than linseed oil. A disadvantage of oils is that they yellow or darken with time, some more dramatically than others. For this reason it is recommended that the use of walnut oil should be kept to a minimum as a medium to aid fluidity or transparency. If multiple layers of linseed oil are introduced, in the mediums added to oil colours, so the effects of future yellowing will be exaggerated.

Dries to a gloss finish.

ADDITIONAL PRODUCT INFORMATION

Apparent darkening of oil paintings kept in dark storage.

When a painting has been stored for a period of time in darkness the artwork will darken. This can be reversed by re-exposure to sunlight. Exposure to sunlight will not reverse the long term effects of oil paint films darkening. Any reversal of darkening will occur within 48 hours of light exposure. Do not over expose artwork to excessive light for long periods of time, The pigments used in the oil paints, especially non-lightfast colours may fade.

WORKING PROPERTIES

Thinning
For best results thin with Distilled Gum Turpentine. However, Artists White Spirit or Langridge Low Toxic Solvent may be substituted. The use of the latter solvents will tend to reduce the fatness of stroke and the oil film will dry with less richness due to the partial destruction of the paint film.

Appearance
Langridge Cold Pressed Walnut Oil is a golden colour liquid with characteristic linseed odour.
The colour of the oil will slightly effect the oil colours with which it is mixed.

Clean Up
Clean brushes with any artists’ solvent (eg Gum Turpentine, Low Toxic Solvent, etc.). For further washing apply a small quantity of Marseille or other pure olive oil soap and massage the bristles of the brush to release any remaining colour. Wash thoroughly in warm water. Leave to fully dry before using for oil colours.

Drying Times
12-24 hours to touch dry.
Full film drying 3-6 months

Available in:
100ml (0391), 500ml (0395), Litre (039L), 4 Litre (0394)