If you’re wondering what the difference is between Solvent-based vs. water-based coatings, this post is for you. Often times coatings will take their name from the resin or binder from which they are made from. Urethanes, alkyds, and epoxies are examples of resins that will give a coating their name. These are the only parts that make up the coatings. Additionally, besides additives, which could have led a coating a certain property, and the pigments that give color, coatings also have an element that will dissolve it into a liquid to make it easy to apply.
This liquefying agent normally is a chemical solvent or water. Which is where solvent based and water based names come from. Which product is right for the job will depend on what circumstance it is being used for. Normally, one isn’t so much better than the other type, but in truth they actually perform much differently based on their situations. Both options will exist within the coating arsenal.
Water based coatings
Water based paints are about 80% of the paints sold today. There isn’t a doubt that this is because of the attraction to water based products, whether it is heavy duty protective coatings or interior house paint it has fewer odors.
When you are working in a poorly ventilated or confined area, the evaporation of solvents can be uncomfortable for anyone and hazardous to anyone’s health. It is for this reason that many projects have fuel storage tanks and railroad cars use water based coatings. This reduces the concentration of flammable vapors and materials that often build up in confined spaces.This doesn’t mean that using them will replace OSHA approved confined space safety measures.
Compliance for environmental areas is also important reason for selecting a water based coating. Most solvents will eventually evaporate into what is known as volatile organic compounds (VOCs). State, national and regional governments regulate VOCs by limiting how must businesses are allowed to emit during a certain timeframe. The EPA sets national rules for the VOCs, but there are some states that have made restrictions tighter which shows the needs to limit emissions.
Water based coatings don’t actually contain 0% solvents. Many will contain co-solvents, which are just solvents that are in lower concentrations and are meant to push the water out of the coating while it dries. Because water based coatings have little to no solvents, they are a great way to lower the VOC output. For some companies, this means spending less on environmental compliance advising or keeps them from having to pay large fines for meeting or exceeding VOC quotas that have been placed for that area.
Solvent based Coatings
These particular coatings are made up of liquifying agents that evaporate through a chemical reaction with oxygen. Normally moving air around solvent based coatings will actually begin to speed up reaction with the air which reduces the drying time.
These particular coatings have a really big advantage over water based paints. They can handle various environmental conditions like humidity and temperature during curing. Humidity can prevent the water in water based coatings from evaporating which makes them impractical in certain areas.
Water based paints are also a challenge for surface prep during any coating projects. Water, even though it is a great substitute for harsh solvents in certain situations, is also a key component for corrosion, the entire reason for industrial coatings to start with. If water makes contact with the substrate before the coating is ever applied, spot rusting may start to happen. To make sure this doesn’t happen, water based coatings have to be formulated so that all the water is drawn out of the surface film before corrosion happens. This isn’t a consideration for solvent based coatings.
In conclusion, although water based coatings are good option for jobs in confined spaces and continuous coating use, they do have weaknesses. Jobs that are in humid, open conditions like those in recoating projects, may benefit still from having the right type of coating. If you want to find which product would be best for your project, we would love to have you contact us for more information.
Phoenix Valley Coatings by All Kote Lining Inc.
If you have structures such as cooling towers, chillers, water basins, water fountains, or other structures that need to be lined with coatings in the Phoenix Valley, All Kote Lining Inc. has the team, skills, and tools to get the job done right. Quality coatings will extend the life of your HVAC and Industrial Equipment and improve the performance by avoiding fouling, scaling, and other energy robbing problems. To learn more about the coatings we offer and the types of applications we use them for, please get in touch with our friendly team.
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