It is not uncommon to shop for more paint than we actually need. It is always better to have excess than insufficient, right? Plus, it could be useful in the future. Nonetheless, sometimes this future is 1, 5, even 10 years later, which can be worrying if you have a significant amount of new or leftover paint to store.
So, how long do acrylic paints last? Acrylic paints may last up to 5 years if opened and over a decade if brand new. However, they must be stored under the right conditions in order to be usable within this timeframe. Keep them sealed airtight and in a cool place away from sunlight.
So if you have a paint stockpile kind of situation, this is the article for you. We’ll discuss the shelf life of acrylic paint, conditions that make acrylic paint go bad, and how to store them appropriately so that they are usable in the future, saving you money.
Do Acrylic Paints Go Bad?
Acrylic paints are far different from something like food items or medicine which you are always conscious of expiring. People go through their entire life without experiencing or even thinking about paint going bad.
It is one of those things that are presumably always in good shape. It is not surprising to find a ton of artists who do not know whether acrylic paints go bad or not.
Therefore, do acrylic paints go bad? Yes, acrylic paints do go bad if not kept correctly. This is usually indicated by the manufacturer, expressly or otherwise.
You can quickly scan through the label on the package, attached leaflets, or websites. You’ll be sure to find some info on how long your acrylic paints can last. They’ll likely survive several years, but are often attached with a warning statement regarding proper storage as a prerequisite to keep it fresh that long.
If you notice anything that is off about acrylic paint, like an unusual smell or consistency; it could be a sign that it has gone bad. Avid painters have probably encountered bad paint before, and are always sure about what they are looking at. But for new painters without much experience with acrylics, it can be difficult to tell.
So, what are the signs that your acrylic paint has gone bad? Separation, gloopy texture, dryness, and a foul smell are all primary indicators of acrylic paint gone bad.
But what makes acrylic paint go bad? Extreme temperatures (too hot or too cold) and contamination are the two common things that make acrylic paint go bad.
1. Extremely Low Temperatures
Nobody intentionally puts their acrylic paints in the freezer. Notwithstanding, sometimes temperatures take a nosedive to freezing and below, particularly during winter. If you store your paints in the garage, an outdoor storage unit, shed, or unheated studio, it will be negatively affected by the extreme cold.
When exposed to extreme cold, acrylic paints react by separating. The water, pigment, and polymer binder have varying freezing points. As a result, the molecules vibrate at different rates, the fast ones pushing the slow ones out of the way, causing separation.
You’ll notice a clear fluid at the top of the bottle, or squirting out first from a tube and the pigment at the bottom. Sometimes the separated paint can be remedied by stirring or shaking the bottle if it didn’t happen too long ago or is not entirely disintegrated.
For paint contained in a tube, you might have to squirt it all out in a new container, then stir and cover tightly. Alternatively, you can knead the tube while closed, but it could get messy real quick if there are any punctures in the tube.
It is worth noting that since the ingredients of the emulsion were not combined manually but through a more complex process, salvaging acrylic paint that has completely separated for too long may be impossible.
However, note that you can refrigerate acrylic paint in an airtight container if you’re going to use it the next day.
2. Extremely High Temperatures
Acrylic paint is a water-based paint. What this means is that the polymer and pigments are suspended in water. Acrylic paint dries up rapidly into a plastic polymer when water evaporates from the emulsion, which is one of its greatest highlights as paint.
On the flip side, when exposed to excessive heat, acrylic paint will lose water even faster through evaporation. The paint starts curing inside the bottle and hardens.
Knowing how tough and water-resistant a coat of acrylic paint is, it is impossible to revive hardened acrylic paint in a bottle or tube. However, if it is in the earlier stages and not yet rock hard, there’s hope. The acrylic paint will be thickened or chunky from losing some water.
You can add a little distilled water and stir to improve fluidity while trying to crush the lumps against the walls of the container.
3. Contamination
Mold is the biggest culprit for making acrylic paint go bad. It will grow quietly in contaminated paints and the wetness and darkness provide the best conditions for growth. Paint can be contaminated by unfiltered water, air, foreign matter, or dirty tools such as brushes or palette knives.
This happens when the acrylic paint is diluted with tap water then stored, while stirring the paint directly in the tin or can, and from the spores the air. If there’s mold already growing somewhere else but around the paint storage area, the air is filled with spores released by the mold.
Moldy paint is evident, especially in light colors. It appears like tiny floating leaves or hairy stuff that is black, brown, green, or whitish. It may be harder to spot mold in dark-colored paints. However, moldy acrylic paint normally emits a foul smell. The fumes are kind of musty, sometimes pungent.
You won’t have to get your nose closer to the paint and smell it (it is not advisable). The smell of bad acrylic paint from mold is really bad. It will get to you and you’ll just know it.
Moldy paint cannot be salvaged and should be disposed of. But you can minimize chances of contamination by always using distilled water to mix your acrylic paint. Ensure brushes and anything that goes in the paint are clean.
How To Store Acrylic Paint
Now that it’s pretty clear what makes acrylic paint go bad while in storage, you ought to rethink your current storage space and make necessary adjustments. Your acrylic paint will last longer stored in one place than another.
The garage, trunks of cars, the floor of your studio, and even backyard sheds are all favorite paint storage spaces for many artists. However, they do not provide the most ideal conditions to keep your acrylic paints usable for many years.
These are areas whose temperatures rise and drop with the weather conditions. Take for example the outdoor shed or garage. These places get extremely cold during winter and can lead to paint separating and freezing.
The trunk of your car or any outdoor shed is even worse during summer because the temperatures inside a car get extremely high and the trunk gets just as hot. We are talking temperatures exceeding 150°F.
Consequently, your paints will begin drying up fast if left there for a reasonably long time. Indoor storage space is the most ideal place to store your acrylic paints.
Of course, there’s the fear of kids, safety, and all that. But there are places in the house less accessible by kids, like the basement or the attic if you have one.
If you don’t, you can store them in your studio on a high shelf or a lockable cupboard. Whichever place you choose, ensure it is clean, dry, and has a stable temperature not below 60°F and not exceeding 80°F, and definitely not on the floor.
Other tips to keep your acrylic paint from going bad while in storage:
- Ensure the paint is tightly capped. Side drips lead to dried paint on the can gutters and tube opening. These usually prevent the cap from screwing all the way down or closing completely. Make sure you wipe clean the opening and lip of the tin or tube before replacing the lid. One trick to prevent such a mess is to install duct tape where you’ll be pouring the paint. This way you can just strip it off when done and close the lid on a clean edge.
- Do not dip anything into the acrylic paint jar or can unless you’re going to use up all the paint in it. If you have to thin the acrylic paint with water or stir the contents to improve consistency, do it in a separate vessel. Any leftover paint that is thinned should be used within a few weeks.
- Replace the lid as soon as possible to avoid contamination from the air. If you can invest in an ozone generator or air purifier to filter the air while preparing your acrylic paints, do it. A heat and cooling fan is also something you might want to consider for regulating temperatures if that is a problem in the storage area.
- Lastly, labeling your acrylic paints is an ingenious way of keeping track of what should be used first. You can put a small sticker indicating the date when you opened each bottle so you can know the most recent and the ones that have been stored for a long time.
And that is how you keep your stored acrylic paint from going bad. Avoid these three things: excess heat, extreme cold, and contamination.
You don’t have to worry about all this if you buy your acrylic paint in small packages or squeeze bottles that you use up in one go or over a few days. However, if you are a paint hoarder and have gallons of acrylic paint stored somewhere, then these guidelines will be of great help.
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