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E-Coating Powder Coating

E-Coating vs. Powder Coating

Among the many types of industrial coatings are electrocoating and powder coating. These two processes are similar, as they both involve applying a coating to a metal product for purposes such as enhancing corrosion protection and wear resistance. But which is superior – electrocoating (e-coating) or powder coating?

Minnesota Industrial Coatings (MIC) provides consistently high-quality industrial coatings, including powder coating and electrocoating (e-coating). MIC professionals carefully guide each project through design to delivery, using our eco-sensitive, quality-driven processes. Contact MIC about your project today!

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Different Types Of Industrial Coatings

Industrial coatings are fundamentally paint applied to various metals like steel or aluminum. They are “caked on” in a way designed to be both aesthetic and protective. There are different industrial coatings to choose from for industrial applications. Some examples of these include epoxies, film lubricants, fluoropolymer, plating, polymers, polyurethane, resins, urethane, and xylene. 

The list of uses for different types of industrial coatings is nearly endless. The main reason for applying virtually any coating is to protect the parts underneath it in some way. 

Specifically, industrial coatings’ most common use is to prevent aluminum, concrete, steel, or other metals from corroding. A common secondary use is to make these materials more resistant to fire or other problems. 

You may think that e-coating and powder coating are similar finishing processes with similar results, but that isn’t entirely true. Both have a uniform, baked-on completed finish. How the finishes are applied, however, differ. The application of both e-coating and powder coating involves an electrical charge, but how the charge is employed also differs, leading to specific results. 

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E-Coating

Also known as electrophoretic deposition or electrocoating, e-coating is a type of industrial coating, considered a “wet process.” It’s more similar to electroplating than powder coating.

The metal is immersed in a bath consisting of paint, epoxy, or other water-based solution. 

The colored particles suspended in the solution are then attached to the substrate with an electrostatic charge, attracting the particles in the solution to the metal surface. 

The electrodeposition process continues until the desired level of coating thickness is achieved. The different thicknesses can be regulated by increasing or decreasing the voltage level of the electrical charge. Once reaching the desired coating thickness, the substrate is removed from the solution. 

The coated substrate is then oven-cured to promote cross-linking and finish “baking” the finish.

E-coating is a popular metal finishing method in the automotive industry. It is often used as a primer coat before paint application to provide better corrosion resistance. 

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Powder Coating

Unlike e-coating, powder coating is a type of industrial coating known as a “dry” process. 

The powder coating process uses an exact, precise combination of curing agents and epoxy resins. 

A coating shop uses a specially-designed spray gun to apply the dry powder particles onto the substrate’s surface. The fact that the powder particles are electrostatically charged is what allows the adhesion to the substrate. 

Just as with e-coating, curing is the finishing step in the powder coating process. Curing causes the particles to melt and catalyzes a chemical reaction that produces the desired finish.

Powder coatings are among the most extensively used finishing methods for materials and products that will directly contact the outdoor environment. They offer excellent weather-resistance, color-retention, and humidity resistance. 

When Does E-Coating Make the Most Sense?

Because of how e-coating is applied, it is typically the better option when coating any pieces that contain hard-to-reach areas. Immersing an object into a liquid solution promotes a more thorough and even distribution of the coating than can usually be achieved with a powder coating spray gun. The application process for powder coating also tends to produce a thicker coating than e-coating.

In contrast, the e-coating process provides exceptional regulation of the thickness level. It’s much easier to produce a thin coating with e-coating than with powder coating. 

The benefits of these two types of industrial coatings are significant in many industries, including the auto industry, where an e-coating is typically applied as a primer before painting for increased corrosion protection.

The Best Of Both Worlds – Combining E-Coat & Powder Coat

A powder coating topcoat placed over an e-coating layer is not a new development. This collaborative process has been employed successfully in many industrial applications. The powder coat and e-coat have no problem adhering to each other as long as adequately cured for the correct amount of time.

Powder coating combined with e-coating provides exceptional protective advantages to your industrial metal products. These advantages include:

Durability: When you add an e-coating to your powder-coated products, you’ll ensure they last longer and stand up better to harsh, outdoor environmental conditions. E-coating is renowned for its exceptional resistance and durability. 

It stands up to both the outdoor elements and indoor factors such as household chemicals. This outstanding performance factor makes it an increasingly popular choice to add a layer of protection in powder-coated manufacturing applications.

Coverage: As we already touched on, e-coating is the better choice of the two for accessing hard-to-reach parts. That said, you might still desire to add the decorative touch that powder coating offers. 

For a combination of great looks and all-encompassing coverage, you can have your manufactured product e-coated, oven-cured, and then powder coated for a stylish finish.

Corrosion & UV Protection: Electrocoating is known for its superior corrosion resistance, which is one reason why so many companies choose this process for their industrial applications. They are often used only as primers or finishes, however, since most aren’t considered UV-stable. Pairing your e-coat with a finishing layer of UV-resistant powder coating ensures both the superior corrosion protection of e-coating and the UV protection of powder coating.

You must check with a qualified industrial coating professional for your manufacturing applications. Certain types of industrial coatings may be better for your industrial project than another. Contact MIC about your industrial coating applications today!

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E-Coating

An Introduction To E-Coating

From automobiles to everyday hardware, customers today demand higher quality and durability from the products they buy. They expect these products to perform well. They also want the finish to look good and resist corrosion for much longer.

What’s the answer to these demands? E-Coating from Minnesota Industrial Coatings.

What is E-Coating?

E-Coating goes by many names, such as:

E-coating is a high-tech process that was only recently developed in the past fifty years or so. 

Electrocoating is an organic finishing method that uses electrical current to deposit paint onto a single component or assembled product. Electrocoating is used across many industries.

When industry professionals discuss electrocoating, they talk about the complete process of surface preparation, coating application, and paint curing. The electrocoating material is a coating applied to the surface with the aid of an electric current. This current will cause the layer to cover recessed areas and edges completely. It is then baked or heat-cured to convert the material to a hard and durable film. This hard and durable film protects the equipment from the elements. The electrocoating forms a physical and chemical barrier, protecting the covered material.

What Materials Can Be Electrocoated?

  • Aluminum extrusions and castings
  • Brass
  • Chrome plate
  • Cold rolled / hot rolled steel
  • Conductive composites
  • Copper
  • Galvanized steel
  • Iron castings
  • Stainless steel
  • Zinc castings

The Industrial E-Coating Process

The industrial electrocoating process is comprised of four distinct steps:

1.) Pretreatment

The material is cleaned, and phosphate is applied to prepare the surface for the application of the e-coat. This process is essential to achieving the performance requirements desired by the customer. 

2.) Electrocoat Bath

Coatings are then applied to the pretreated metal in an electrocoat bath using precisely calibrated equipment. The e-coat bath consists of 80-90% deionized water and 10-20% paint solids. 

3.) Post-Rinsing

Post-rinsing, which occurs next, enhances the coating’s quality and enables the recovery of excess paint. During the e-coat process, paint is applied to a part using a fixed amount of voltage to achieve the desired film thickness. Once the coating reaches the prescribed thickness, the coating process slows down. As the part exits the bath, paint solids that cling to the surface are rinsed off to maintain application efficiency and aesthetics. This residue material, called “drag out” or “cream coat,” is returned to the tank, enabling the e-coat process to achieve application efficiency rates above 95%.

4.) Heat Curing

After the coated part exits the post-rinse phase, it is placed in a bake oven that cures the paint film to maximize its performance. The minimum bake time is 20 minutes at a temperature of 375°F for most e-coat technologies.

What makes electrocoating unique from other finishing methods is the heat curing in the final step. 

Benefits of E-Coating

1.) Superior Corrosion Resistance

E-coating makes products last longer, protecting the metal underneath the coating. Because of this corrosion resistance, e-coating is good on its own or as a base coat for other finishes.

2.) Better Coverage In Tight Or Hard-To-Reach Areas

Because of how the electrocoating is applied, it’s typically the better option when coating any parts that contain hard-to-reach areas. 

3.) Uniform, Even Coat

When the part being finished is immersed into the liquid, the coating is more evenly and thoroughly distributed than, say, a spray gun application. You can count on no dripping, no pooling, and no gaps.

4.) Better Control of Paint Thickness

This dipping process can also result in a thinner coating than powder coating.

5.) Efficiency

Virtually all unused paint is recovered, leaving almost no waste. Also, most e-coating systems are automated. This automation means that the amount of paint applied to a product can be precisely controlled. This precision results in minimal waste, unlike powder or paint overspray.

6.) Environmentally Friendly

Electrocoating is environmentally friendly. Many manufacturers choose electrocoating because it produces virtually no HAPs (hazardous air pollutants) or VOCs (volatile organic compounds). The process is also RoHS, OSHA, and EPA compliant.

Minnesota Industrial Coatings is unique because it makes extra efforts to ensure environmental friendliness. The waste systems we use for the waste products from the pretreatment process can keep the release of hazardous materials well below the regulatory requirements.

Does Electrocoat Need To Be Top-Coated?

No, not always. In many applications, electrocoat can be considered the “final finish” on a product.

However, electrocoat does not hold up well with UV rays. Thus, using a top coat on any parts that will have UV exposure is an excellent idea. When you pair electrocoating with a topcoat, such as powder coating, it’s an outstanding anti-corrosion primer. These topcoats also allow for a variety of color and gloss options that aren’t easy to create with only electrocoating.

Electrocoated Products

Electrocoated products first made their debut in most homes as parts of cars. Other industries quickly caught on to the revolution and how easy it was to make things last longer with electrocoating. 

Now, you are surrounded by electro-coated products in your home and business, and you may not even know it. Some of the most popular products surrounding you every day are:

  • Eyewear frames
  • Giftware 
  • Hardware 
  • Home Appliances
  • Household or business appliances
  • Jewelry 
  • Sporting equipment

Where Are E-Coated Products Used?

The process of e-coating is used for a wide variety of metallic products. Wherever there is a need for exceptional coating performance over a metal substrate, you may find electrocoating used as a primer or as a finished coating. 

But some industries that regularly use electrocoating include:

  • Aerospace manufacturers
  • Agriculture & agricultural equipment
  • Appliance manufacturers
  • Automobile and automotive parts
  • Fasteners 
  • Fixtures 
  • Lawn & garden equipment & furniture
  • Marine & marine components
  • Metal office furniture
  • Transformers 
  • Trim appliances
  • …& many more industries

Do you have a finishing project, and you are interested in learning more about e-coating? Contact Minnesota Industrial Coatings to submit an RFQ.