Why do Whites eventually yellow?
If you’ve been painting furniture regularly, it’s inevitable that at some point you would have run, or going to, run into this problem.
Did you know that all bright white paint will yellow a little over time?
I recently had a lady tell me that a piece she’d painted in bright white, quite quickly turned yellow after applying a coat of polycrylic over it. Another lady said to me that she’d applied tung oil over her bright white painted pallet board, and that yellowed over the course of about a month.
My own our white end table after about a year, has turned decidedly yellowish.
So what’s the deal here? Should we be prepping better? Sealing better? Or just not use bright white paint?
Here is what you should know to protect your self from the dreaded "yellowing effect".
First of all, there is no way to reliably predict whether or not a piece painted in bright white will yellow over a period of time.
Sometimes it would. Other times it wouldn’t. Sometimes you will see the effects immediately, other times, it may take months, or until a change in weather/temperature/humidity, may cause tannins in the wood to bleed through, yellowing the paint and thus the top coat.
Sometimes, the top coat activates the tannins in in wood, and causes them to bleed through to stain the piece. Other time, when the top coat pools up in the sculpted details, cracks and crevices of your piece of furniture; any where where the top coat can collect; the yellowing may intensify to a much higher degree.
The reason we don’t see as much of this happening with other colours is because a pure, bright white is actually more transparent than most colours (with lesser pigmentation; hence the need for additional coats most of the time).
How would you protect yourself.
1) Your best bet is to use a self sealing paint (such as from either the Frenchic Lazy Range with a built in wax; or the Frenchic Al Fresco Range, with a built in top coat). Bear in mind though that a piece with a built in wax isn’t ideal for high frequency usage areas.
2) You could try adding a little of the paint you are using to the first and second application of the top coat, to build a non-yellowing durability in layers. The final layer of top coat though should be as is, with no paint added to it.
3) Before painting on your first layer of white, always apply a stain blocker, a shellac-based primer, or the all-natural, chemical-free Frenchic Finishing Coat, to help prevent bleed through.
4) If you plan to paint over either teak wood or mahogany, do so knowing that there is a large chance of your white paint showing bleed through and yellowing. The oils and tannins in teak are prone to start showing through over time, causing a fair bit of yellow stain. Many mahogany and other mid-century modern pieces (from the 1930s to 1950s) contain, or are finished with, aniline dyes. You know that’s the case when you see that famous pinkish bleed through seeping through your whites.
5) Not every brand of paint is compatible with another brand’s top coat and therefore may react with a colour change or yellowing. Always, always test your finish on an area that won’t be seen, such as the back of a piece (if it will be up against a wall) or the inside of a door, before you go full steam ahead.
And when all else fails, embrace the flaws. Turn it into a unique design feature. No one will know, if you don't tell...