It is best to clean your brushes before the paint dries, of course, but if your brushes have dried paint on them, you can still salvage them and put them to good use again.
To remove latex paint that has recently dried, use hot water and dish soap by first washing the brush thoroughly by filling a container with hot water and a couple drops of dish soap. Allow the brush to soak.
Swish the brush in the water and press the brush against the edge of the container to loosen the paint. Empty and refill the water if the water gets too dirty.
You can also use a comb or utensil to loosen the paint from the brush. Next, rinse well, and let the brush dry.
An alternative to this method and for tougher jobs, is to try using vinegar. With this method, you can heat the vinegar on the stove and soak the brushes in the hot vinegar. Then remove the brushes from the vinegar and allow the brushes to cool, You can use a comb or a wire brush to loosen the paint from the brush, then rinse with water and let dry.
Other Types of Paint
To remove almost any type of paint from a paint brush and when working with oil based paints, paint thinner will always do the job.
You may also use a number of other chemical products, such as “Brush Cleaner”, which is made particularly for the purpose of removing paint from paint brushes. You can soak a brush in a jar with paint thinner or chemical solution overnight.
Afterwards, you can use a comb or wire brush to remove any remaining paint from the brush. Then rinse the brush either with clean paint thinner if removing oil-based paint or water if removing water-based paint.