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oil painting linseed oil
What type of linseed oil is used in oil paint?

What is the difference in the raw water and boiled linseed oil used in an oil painting? Is there an oil painter who could answer this for me? Can I use acrylic to get the same effect, and how can I do it?

First, acrylics and oils have very different properties. Each has its place. There are some effects of oil painting that you just can not get from any other means. The opening time (the time that the paint remains wet and workable), and the explosion of color enhanced by the quality of oil is a transparent integral part of the advantage over other media. I encourage everyone to learn to use oils. The center is rich and offers many possibilities, if you understand. Now, there is no rule that states that you must use a form of oil in the other mediums. Linseed oil is used in a variety of ways to achieve different effects. It is available in cold presses, cooked, alkali refined, sun bleached, sun thickened, just to name a few. Stand oil is a polymerised form of linseed oil. Raw or cold pressed oil dries more quickly than “refined” or “boiled” linseed oil. There are advantages in the oil blend to make certain properties in painting. Paint makers use these properties to achieve certain effects in painting. It would make you a better artist to gain a better understanding of these qualities. The main differences are the result of two important physical properties of drying oils: the degree of polymerization and the rate of acid oil. Both properties are affected by oil treatment – usually using heat – change in one or two of them. Heat treatment of oil means that the so-called “body” oil, which is the preferred term for what some call “maintenance oil.” Linseed oil has good brushing properties. Refined linseed oil has a short texture, buttery, which lends itself easily to be brushed. The flow of these pictures is poor, however, and leave brush marks. The raw linseed oil has an acid of 4-7, while alkali refined linseed oil less than 1. Exceptions to this, special refined oils are made with high acid values to give a better pigment wetting property. The remarkable property of linseed oil is its excellent durability. It is therefore most widely used in painting than any other drying oil. Bodied oil is a polymerized product by heating linseed oil refined at high temperature for a certain period of time when the color and the number of significant weak acids, heating, either in vacuum or under a layer of inert gas. Bodied linseed oil has an acid in a wide range, depending on how hot it is. Blown linseed oil is essentially oil that is partially oxidized by passing air through the high temperature. Partially oxidized oil is very viscous. The typical viscosity is Z-2 to Z-4 Gardner Holdt units. The acid number of blown linseed oil is generally high. A small amount of blown linseed oil can be added to very short paint. Heating an unbodied oil, adding driers and cooking it in an open or closed kettle is how boiled oil was made. Today, liquid driers are added to refined oil and heated briefly at lower temperatures to effect a complete solution. Bodied oil has better color retention than unbodied oil. This can be understood if one considers that we have an oil that was halfway to a dry film by polymerization. The bodied oil dries faster and absorbs less oxygen when dry. The polymerized dry film has oxidized less and therefore holds more color. Bodied oil has a better color retention than blown oil. It is also easier to understand why oil that has been partly oxidized by blowing will end up with a greater degree of oxidation when dry than one in which some of the oxidizable bonds have been removed by polymerization. Blown oil has poor initial color, due to oxidation during the blowing process and poor color retention due to the further oxidation while the film is drying.

Blown oil has the best flow and leveling properties. Due to the viscous nature of bodied and blown oils, they have a tendency to be more difficult to brushing, because they feel sticky. It is more difficult to separate large molecules in viscous oil than it is smaller molecules in thin, unbodied oil.

Bodied and blown oils have a much brighter sheen or gloss an unbodied oil. Blown oil has the best wetting properties due to the higher acidity value. Large molecules are much less likely to penetrate a porous surface which means bodied oils holdout better than the thinner oils. Blown oil can be used to make water-sensitive paint less sensitive as it tolerates large amounts of water. The increasing polarity caused by double bonds of blown oil gives it better properties of resistance to moisture, better flow and leveling properties.

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