Can You Use Polyurethane Over Acrylic Paint?

Have you used acrylic paint on items around your house to help give them a fresh look or to add color? Have you found that over time the color wears or the paint chips? Are you looking for options to help preserve the look of your freshly painted item? Are you wondering, can you use polyurethane over acrylic paint?

You can use polyurethane over acrylic paint. It can be used to preserve the paint from discoloring or being chipped. As long as you prepare the acrylic paint and apply the polyurethane correctly, it will help preserve acrylic paint.

In this article, we explore how to use polyurethane over acrylic paint. We’ll look at what options there are, how best to apply polyurethane over acrylic paint, and some key considerations to keep in mind.

What Is Polyurethane?

Polyurethane is a finishing product that can be used to cover and protect numerous surfaces. It goes over other finishing materials such as acrylic paint to help protect the paint and keep the colors looking great for a long time. It is applied like a coat of liquid over the surface of the paint by brush or can be sprayed on. Polyurethane can be either oil-based or water-based.

Can You Use Polyurethane Over Acrylic Paint?

You can use polyurethane over acrylic paint. If you have something that you put a fresh coat of acrylic paint on, once it’s dry you can protect it with a coat of polyurethane. For the best results, there are some steps that we’ll explain below in detail.

Will Polyurethane Ruin Acrylic Paint?

Polyurethane will not ruin acrylic paint if it is used correctly. When finished painting, let the paint dry fully. The time for acrylic paint to dry can vary depending on what you are painting it on and how thick each coat of paint is. Once the acrylic paint is dry, choose the type of polyurethane that will work best.

What is the Best Polyurethane for Acrylic Paint?

When choosing what type of polyurethane to use, consider the size of the item. Polyurethane comes in both liquid and aerosol forms. You can buy both the liquid and spray polyurethane in different sizes, so choose whichever one is best for your project.

How Long for Paint to Dry Before Using Polyurethane?

Thin layers will dry in 30 minutes or less, but thicker layers of acrylic paint can take several hours or more. Make sure the paint is completely dry before applying polyurethane to avoid smearing the acrylic paint you want to protect.

What to Consider Before Using Polyurethane on Top of Acrylic Paint?

Before using polyurethane on top of acrylic paint, there are a few things to consider. First, look at what has been painted. Depending on the size of the item painted, use polyurethane that can be applied with a brush or from a spray can. Look at the size and amount that needs to be used and how hard it would be to fully cover it in polyurethane by using a brush.

Next, consider whether to use oil-based or water-based polyurethane. Oil-based polyurethane has a slightly amber tone to it which can be seen over your acrylic paint. It can affect your paint colors in ways you may not want.

Water-based polyurethane often looks milky white in the can but once it is applied and dry, it is completely clear. Depending on the type of finish you want, you can get polyurethane with either a gloss, semi-gloss, or satin finish.

Once you know what kind of polyurethane finish you want, you can look at how to best apply it.

How to Seal Acrylic Paint with Polyurethane.

Once you are finished painting and the acrylic paint is completely dry, it’s time to seal your handiwork by making sure the entire surface is coated in polyurethane. You’ll want to apply 2 -3 coats of polyurethane in order to make sure it is completely sealed and ready for use.

Prepare Surface

After the acrylic paint is completely dry, prepare to apply the polyurethane. Depending on the thickness of the layer of acrylic paint applied, the drying time could take anywhere from half an hour to four hours or more. Once it is dry, wipe it off with a cloth to ensure there is no dust remaining on the surface so it won’t be sealed in by the polyurethane.

Apply Polyurethane

There are 2 ways to apply polyurethane. Depending on what you have painted, its size, and what you wish to cover with polyurethane, it might be best to apply the polyurethane with either a brush or by spraying it on. Before applying polyurethane though, remember to make sure the acrylic paint is dry and clean and prepare the area where you are going to be applying the polyurethane.

It’s often best to lay something on the floor to catch polyurethane drips or settling spray. This can be as simple as tearing apart a box and laying it out on the floor or using a drop cloth if you have one available.

Next, make sure that the area is well ventilated before applying the polyurethane. Polyurethane contains VOCs – Volatile Organic Compounds – which are harmful gases emitted from polymers such as polyurethane which can have both short term and long term effects on your health. So, ensure the painting area is well ventilated. Check out this link for more info on VOCs.

Once you’re ready to apply the polyurethane, decide whether to use a brush to apply it in liquid form or to use a spray can to apply it. If applying it with a brush choose a good quality brush. Minwax, a supplier of quality polyurethane, suggests using  Polyurethane China Bristle Blend Brush. However, a good quality brush can be found at any local building supply store such..

Next, open the can of polyurethane and stir it well so that it doesn’t settle on the bottom of the can. Don’t shake the polyurethane as that will create air bubbles that can spoil the finish. Apply a thin coat of polyurethane evenly over the surface using the brush until the entire surface is covered. Let the first coat dry for up to 6 hours. Once the first coat is dry, sand the polyurethane surface lightly with sandpaper and then apply a second coat. Two coats should be enough but if you want it to be really durable, then, feel free to add the third coat. Again, make sure to wait 4-6 hours between coats and lightly sanding before applying the third coat.

If you decide to use polyurethane in a spray can, the process is similar to using a brush. Make sure that there is something on the floor to protect it. You may want a bigger surface area covered, possibly even the walls around the object, as the airborne spray will travel further than just drips of polyurethane off a brush.

Make sure the acrylic paint is dry and wiped down with a cloth, so it is dust-free. Then spray a thin layer onto the surface. Shake the can of spray polyurethane for a couple of minutes before use. Be sure to use a slow steady motion over the entire surface for an even coat. Keep the spray nozzle about a foot away from the surface as you apply it.

Let it dry for 4-6 hours and then lightly sand the first layer before applying a second coat of polyurethane. Again, to ensure greater durability, a third coat can be added. Just be sure to let the second layer dry and sand lightly before applying another coat. Once the polyurethane is applied, let it stand for at least 24 hours before use.

Clean Up

Once the polyurethane has been applied over the acrylic paint, it’s time to clean up. Use mineral spirits or paint thinner to remove splatters or anywhere that it may have been applied too thickly. Mineral spirits and paint thinner are very similar but mineral spirits are normally a little more expensive as they are more refined than paint thinner, and have a lower level of VOCs. Either one should do well for cleaning up, but be sure to use them in a well-ventilated area.

Can I Use Minwax Polyurethane Over Paint?

Minwax polyurethane is a common polyurethane that is easily found in most building supply stores. In addition to being easily accessible, Minwax is a high-quality polyurethane that when applied correctly, provides long-term protection.

It comes in both liquid form and spray can. Depending on what you are looking for, you can get it in gloss, semi-gloss, or satin finish.

Conclusion

After you have applied acrylic paint to a piece of furniture or other item, it’s a good idea to seal it with polyurethane. Depending on the size of the item painted, use either spray or brush-on polyurethane for the best result. Hopefully, we’ve provided you the information needed to seal and protect your acrylic paint project. Please feel free to share with your friends or co-workers if you found this article helpful, and be sure to let us know in the comments below how your project went.