What Is The Difference Between Enamel And Polyurethane?

Last Updated on August 13, 2023 By Emma W. Thomas

Enamel is a hard, glossy paint finish, while polyurethane is a clear, protective coating. Enamel provides color and durability, commonly used for surfaces like metal and wood. Polyurethane offers a transparent, tough layer for wood, floors, and more.

Difference Between Enamel And Polyurethane

EnamelPolyurethane
DefinitionEnamel is a type of paint that forms a smooth, hard, and glossy finish when it dries.Polyurethane is a type of protective coating that is applied over a surface to provide a durable and resistant finish.
CompositionEnamel paints are oil-based or water-based, containing pigments, resins, and solvents.Polyurethane coatings are typically made from polymers formed through the reaction of isocyanates with polyols.
AppearanceEnamel paints create a glossy or semi-glossy finish with a smooth and reflective surface.Polyurethane coatings can be glossy, semi-glossy, or matte, depending on the desired effect. It can provide a clear or lightly tinted finish.
ApplicationEnamels are commonly used for decorative purposes, including furniture, trim work, cabinets, and walls.Polyurethane coatings are primarily used for protection and durability on surfaces such as wood, metal, concrete, and plastic. They are often applied on floors, tabletops, cabinets, and outdoor furniture.
DurabilityEnamel paints are generally durable, but they can be more prone to chipping and peeling over time.Polyurethane coatings offer excellent durability and resistance to abrasion, chemicals, UV rays, and moisture. They are known for their long-lasting protection.
Drying TimeEnamel paints have a longer drying time compared to polyurethane coatings.Polyurethane coatings dry relatively quickly, allowing for faster project completion.
Application ProcessEnamel paints can be applied with brushes, rollers, or sprayers and may require multiple coats for optimal coverage.Polyurethane coatings are typically applied with brushes, sprayers, or foam rollers. They often require fewer coats for adequate coverage.
OdorEnamel paints can emit strong odors, especially oil-based variants.Polyurethane coatings may have a mild odor during application, but it typically dissipates quickly.
CleanupEnamel paints are generally cleaned up with solvents like mineral spirits or paint thinners.Polyurethane coatings can be cleaned up with soap and water or specific cleaning products designed for polyurethane.
Environmental ImpactTraditional enamel paints contain volatile organic compounds (VOCs) that can contribute to air pollution. Low VOC enamel paints are now available as an eco-friendly option.Polyurethane coatings can also contain VOCs, but low VOC or water-based options are increasingly popular for reducing environmental impact.

About Polyurethane 

Polyurethane is available in water-based and oil-based varnishes, which contains more plasticity than any older paints or varnishes found. It is basically a cross-linked polymer. 

Water-based Polyurethane is popular because it is low in odor and toxicity. It is used in anything that does not get exposed to extreme climate conditions.

Oil-based Polyurethane is more durable than water-based ones, mainly when it comes to resisting heat. It takes more time to dry than water-based Polyurethane. You can also find water-based oil-modified Polyurethane. This is comparatively new in the market. It is better in the sense that it consists of the durability of oil-based Polyurethane and the cleanup of water-based ones.

Also, polyurethanes are not necessarily smooth, high gloss, and decorative. Generally, they are only referred to as the topcoat. This paint is used primarily as a shock absorber and also in shoe soles.

Polyurethane may come with a single or dual coating. In the latter coating, the former components consist of colored pigments and many other ingredients. Here resin is usually found as polyester or acrylic. And the final component mostly comprises a clear polyisocyanate. When these two components are mixed, it results in the formation of Polyurethane.

Where To Use Enamel Paint?

Enamel paint is widely used to paint woodwork. They easily get glued to old wood because of their smooth and dry coating texture. You can use it outdoors, in house trims, in hardware, stairs, or in patio furniture as it can handle temperature variations. It is better to use a primer coating to get the painted texture to last for a long time.

Can We Use Enamel Coating On Cars?

Enamel car paints are available in the market to paint cars, buses, trucks, and other vehicles to provide a very smooth and clean look of the vehicle. It is mainly designed to use in vehicles for its ability to withstand any facet. Along with this piece of information, you must know its pros and cons. So let’s see them.

Pros:

1. Changing The Color Of The Car: Whenever you want to change the color of your car, choose Enamel paint. It is always better to choose a paint which has a hardener in it to cover.

2. Clear Coating Finish: Generally, enamel car paint can be applied as a clear coating without any problem. But if there is an issue to adhere to, then wet sand the surface and apply a clear coat.

3. Acrylic Lacquer: Enamel car paint with acrylic lacquer is a suitable choice for those who do not want to undergo a car painting hassle.

Cons:

1. Enamel Car Paints With A Clear Coat: All the brands of Enamel car paint are not created in the same way. As a result, some brands will not adopt a clear coat. So it is better to check the enamel car paint manufacturing you plan to use. It will help to get an idea of whether the paint will accept a clear coat or not.

2. Time-Taking Process: Enamel car paints are required to bake onto the car. Unlike other car paints, it cannot dry well on its own.

3. Costing Charge: Although enamel car paints are originally cheaper yet the additional cost of hardener and other amenities is higher the price. You can find multiple paint alternatives to the Enamel car paint. And yes, they are cheaper in price.

Do We Need To Use A Primer Before Applying Enamel Paint?

It is better to apply a primer before the application of Enamel paint, especially if you are thinking of painting cabinets, furniture, or any interior surfaces. Choose the primer that is best suitable for your surface. Note that some brands manufacture inbuilt primers in enamel paints. So you need not have to buy a primer separately.

How To Apply Enamel Paint?

Learn where and how to apply enamel paints here. We have divided the process into 3 steps for an easy guide.

1. Select The Correct Material For Your Work

● Enamel paints are available in both oil-based and water-based forms. The oil-based paint can be mixed and applied to get a smooth finish. However, with the recent craze for non-toxic alternative paints, water-based paint came into popularity. It is very easy to use and also dries faster than the oil-based Enamel paint.

● There are many Enamel paint manufacturing companies available in the market. Take a look at these paints and choose the suitable one for your job.

● Always choose a high-quality brush that has the exact stiffness and filament type for the paint you have chosen. Brushes with an angled bristle edge are ideal for painting an even finish coating.

2. Apply Enamel Paint

● It is nicer, to begin with, a primer in order to prepare the surface for a topcoat paint. 

● Use a second-to-tip-off technique after brushing the top layer of paint. Make the strokes look fluid as possible. You can also use a spray bottle to evenly distribute the paint. Otherwise, it is very easy to make the imperfections noticeable.

● Try to apply two coats instead of one coating. This will not only help to make the paint durable but also give a smooth and seamless finish.

3. Dry And Clean The Paint:

● Generally, oil-based Enamel paint takes around 8 to 24 hours in normal conditions to dry because of its thickness. But if you are using water-based Enamel paint, then it will not take more than 1 to 2 hours or can even dry up faster.

● During touch-up, apply a thin layer of paint at a time to keep the surface uniform.

● Primers are not generally required during touch-ups unless you are stripping off the paint.

● For cleaning, you can simply wet a piece of cloth or a towel and mix it with lukewarm water and mild liquid detergent and wipe off the dirt and debris away.

Are Clear Enamel And Lacquer Similar?

Yes, there is typically one similarity between clear Enamel and lacquer. Both of them come with an acrylic formulation. Apart from this, there are a few dissimilarities between them.

Clear EnamelLacquer
Clear enamel dries out and gets cured on the top of a painted surface. Lacquer basically dries out but cannot cure the painted surface.
It has chemical substances that cause a reaction to the surface.There is no scope of any chemical reaction with the surface.
You cannot mix it with paint.You can mix it into the paint.

Can We Apply Polyurethane Over Enamel Paint?

In most cases, you can apply Polyurethane over enamel paint. But if the Enamel is super glossy, you will have to scrape the surface before you start applying the first coat of Polyurethane. Just make sure the Enamel paint has completely cured before you begin to apply Polyurethane. It takes one week on average, but if it is latex-based, Enamel can take a minimum of 20 days to cure fully. Wait for the time being; otherwise, you won’t be able to apply Polyurethane over enamel paint.

Are PU And Polyurethane Similar?

Yes, PU means Polyurethane. PU paint helps to provide a fine and smooth texture to the wooden, metal, glass, and plastic surfaces.

What Are The Pros And Cons Of PU?

Almost everything comes with both pros and cons. PU paint is no exception.

Pros: 

  • Protects from fluctuating temperature.
  • You can get a matte finish to a super glossy finish.
  • Prevents the surface from getting any scratches or stains.
  • Low in odor.
  • Environment-friendly.

Cons: 

  • It tends to get darker over a period of time.
  • It requires extra attention during implementation.

Is Polyurethane Safe?

The versatility and durability of Polyurethane make it easier to use in almost everything. But is it safe? The concerned consumers and organizations are raising this question to research the potential risk polyurethane carries.

Unfortunately, the researchers have found Polyurethane contains isocyanate. Isocyanate is a harmful compound that can cause lung irritation and asthma attacks if exposed for a long time. Also, it can cause skin irritation, severe headache, and several other health problems.

How To Protect Ourselves While Applying Polyurethane?

It is recommended to apply polyurethane foam in a well-ventilated area. You should always wear an eye protector and face mask while applying it. You can also turn on the fans in that area to dry up faster. Also, do not smoke in that area.

Is There Any Alternative Available For Polyurethane?

Yes, there are many non-toxic alternatives available for Polyurethane. They are Green Polyurethane, Hard Varnish, Tung oil, Candelilla Wax, and AFM-safe coat.

Final Verdict

Enamel paints dry up hard and cannot be rewet. It can be used in cars, buses, trucks, and other vehicles. It is also very easy to clean. 

PU or Polyurethane is suitable for application in metals, glass, wooden surfaces, and more. Although it is low in odor, still research studies have shown the potential harm it can do to human health. It is advisable to take necessary protections to minimize its danger. Likewise, there are few non-toxic alternatives that have arrived on the market. So choose the right paint according to your job.

References:

https://www.diygeeks.com/polyurethane-vs-enamel-paint/
https://www.ehow.com/info_7931658_urethane-vs-enamel-paint.html