If your oil-primed canvas or panel appears yellow when it arrives, this is most likely due to a natural process called Dark Yellowing.
Dark yellowing occurs when oil-based materials, such as linseed oil used in traditional oil primers, are stored in low light or darkness. Without light, the oil oxidises differently, causing a temporary yellow or slightly dull appearance. This is most noticeable on white or pale surfaces.
This is a common characteristic of oil-primed surfaces and not a fault with the product. Many high-quality traditional oil primers will show this effect if kept in dark conditions during storage or transit.
The good news is that dark yellowing is reversible.
When the canvas or panel is exposed to natural or moderate light, the yellowing will gradually fade as the oil film rebalances.
How to reverse dark yellowing
Place the canvas or panel in a well-lit area (avoid direct, harsh sunlight)
Allow it to sit in consistent natural or ambient light
Over time, the surface will return to its intended colour
The time this takes can vary from a few days to a couple of weeks, depending on the level of yellowing and light conditions.
Dark yellowing is simply a characteristic of traditional oil-based primers, and once reversed, the surface will perform as expected.
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