How to Clean Dried Polyurethane from Paint brush?

How to Clean Dried Polyurethane from Paint brush

Your paintbrush is now covered in dry polyurethane paint. You’re ready to use it again but the paint isn’t going anywhere.

So just how to clean dried polyurethane from paint brush without affecting the brush bristle?

Dried polyurethane from a paintbrush is a common problem that many amateur painters encounter. Cleaning dried polyurethane from a paintbrush can be quite a difficult task especially if you do not know the steps.

You can get the information about how to clean your paintbrush here in this article!

Types of Polyurethane

Polyurethane is a great material that can be used for numerous things, from creating furniture to protecting your home’s floors to making the surface of your car shine. It is a hard, flexible resin and a waterproof polymer that provides resistance to chemicals.

Before we get into the specifics of Polyurethane removal, we should look at the different types of polyurethane and how they react differently to the different cleaning methods.

Generally, polyurethanes can be categorized into two types:

  • Water-Based Polyurethane
  • Oil-Based Polyurethane

1. Water-Based Polyurethane

There are a few different types of polyurethanes, each of which is useful for different applications. One of these is water-based polyurethane.

The attributes of this type of polyurethane include low odor, no toxicity, environmental friendliness, and ease of use. Just by using only tap water, you can take off the polyurethane.

2. Oil-Based Polyurethane

Oil-based polyurethane is cheaper and more complex than water-based ones. If you have a chemical, you can clean the oil-based polyurethane smoothly.

You need to keep your doors and windows open for a few days. It may cause odors to settle into curtains, cover sheets, and clothing.

Things You Should Know Before Cleaning Dried Polyurethane from Paintbrush

Brushes are one of the most important pieces of equipment used in painting and drawing. It’s a good idea to take the time to properly care for them since it will ensure that they’re in good shape for years to come.

Brush bristles are one of the most important parts of your brush! They do all the hard work for you and interact with the paint that you’re using. Some of the chemicals that are used in paints aren’t the best for your brush, though.

Regardless of whether or not they are natural and real hair, or synthetic hair, they still need to be maintained to retain their quality year after year, and how often they are used.

Having a good clean-up technique that will assist you to clean your brushes or at least as quickly as you can so that the paint does not have the chance to turn hard and stuck to your brush bristle which can ruin the brush.

If you have dried polyurethane stuck on your paintbrush then do not worry, with a few simple steps it’s possible to store them easily.

Supplies You will Need to Get Rid of from Dried Polyurethane

When cleaning brushes, it is very important to remember that there are some key things that you will need to get the paint off, especially if it is dried. Natural bristles are not the same as dried paint, so not all cleaners work in the same way. It is always best to use proper supplies for a successful result.

You might already have a few of these at home already, and then you will only need the rest if the dried-up paint is too stubborn and simply refuses to come off with just the basic cleaning methods and supplies.

So, what do you need?

  • A brush comb.
  • Paper towels.
  • plastic containers or glasses.
  • plastic bag.
  • Some mineral spirits.

How to Clean Dried Polyurethane from Paint brush: Step by Step Guideline

Step 1: A Paper Towel can be Used to Remove the Polyurethane

First things first, saturate a small section of a paper towel with some mineral spirits. If you only have paint thinner or lacquer thinner on hand, you can stick with mineral spirits because sometimes they can damage the brush and strip it.

You’re going to use this to get rid of the polyurethane from brush bristles before soaking. This is to start the process and lower the amount of polyurethane that needs to be removed overnight.

After just one soak, this will leave you with less work in the long run. Make sure you use gloves so you don’t get mineral spirits on your hands, and make sure the area you’re working in is well ventilated.

Step 2: Put Mineral Spirits in the Container

If you fill your first container with mineral spirits you will be able to place the bristles in it and have them saturated.

Measure this to make sure you only soak the part of the brush bristles that have the polyurethane on them. The metal part of the brush should not be touching the mineral spirits.

Step 3: Place Brush in the Container

It’s time to put the brush in the container with the mineral spirits. If you swirl the brush around to get the solvent into the bristles, you’ll get the most cleaning power. It is possible to leave the brush in the container for several hours.

You may need to allow it to sit a bit longer depending on how much has dried. An all-night soak is generally the way to go.

Step 4: Transfer Spirits that are Dirty

After you have completed your brush cleaning, you will need to dispose of the used solvent. If your brush cleaner is a concentrated form of alcohol, you should dispose of it in an appropriate manner. Otherwise, you can use any type of waste container to store it for later disposal.

Because mineral spirits, paint thinner, and oil paints are caustic and hazardous, you have to dispose of them at a hazardous recycling plant near you. These things need to be dealt with with care.

Step 5: As Required, Repeat the Process

Place the same amount of mineral spirits into another container and swirl the brush around again. You won’t need to let the solvent soak again because you’ll probably see some promising results just from agitating it.

If you want to see the results you want, you can allow the brush to soak for a few hours and repeat the process.

Step 6: The Brush Should be Rinsed with Hot Water

Once you have removed the majority of the paint from the paintbrush, you can use some hot water to soak the brush.

If you feel like you need more help, you can use some dish soap to create a soapy water mixture. You can use a brush comb at this point to get through the bristles and get rid of leftover paint.

Step 7: Paper Towels can be Used to Dry

To dry the brush bristles, use some paper towels and pat them dry. If you pull too hard, you can loosen the bristles and shorten the life span of the brush.

When you’re ready to store your brush for its next use, I would recommend wrapping it in plastic wrap and putting it in an old newspaper. The bristles will be perfectly straight and clean when you need to use them again.


Q.1 How to stop polyurethane from drying on a brush?

Ans: If you only need to stop overnight or for a few hours, there are a number of tips to keep your brush ready for use the next day. If you keep your brushes in water or wrap them tightly with food wrap, you can keep the air out of the brush and keep it moist.

Q.2 What is the best way to clean a dried polyurethane?

Ans: The best way to clean a dried polyurethane brush is to use a mixture of water and isopropyl alcohol. You’ll find that this mixture will remove the polyurethane residue without damaging the brush. You’ll also want to make sure that your brush isn’t full of solvent or paint because you don’t want the paint to dissolve in the alcohol.


It’s important to remove the dried paint and to do so with the right tool for the job. A brush can leave behind a sticky and dried residue that is hard to remove without scratching the finish of your workpiece.

There are a number of methods that can be used to remove dried residue like polyurethane. You can use a mixture of acetone and water to remove the dried polyurethane from your paintbrush. All you need to do is to mix equal parts of acetone and water. A damp rag can be used to apply the solution to the surface, and then it can be wiped clean with a dry rag. So try the method and then see the results!

How to Clean Dried Polyurethane from Paint brush?

Leave a Reply

Your email address will not be published. Required fields are marked *

Scroll to top