Water-based paints use acrylic resins. But the resins are carried to the substrate using water -- unlike urethane auto paint which uses a solvent to carry the acrylic resin to the substrate. Water-based paint can be used for complete paint jobs, or to produce decorative graphics and highlights on pre-painted cars. Water-based paints have the same colour range as urethane paints.
Water-Based Paints Are Non-Toxic
Water-based paints only produce water vapour while they are curing, unlike urethane paints which release volatile organic compounds that are toxic to humans and the environment. Urethane-based paints and water-based paints are the same are the same in many ways, but they have different carrying agents and binders. This is what makes then react differently to similar conditions.
Water-Based Paints Are Easy to Use
Urethane paints have to be mixed in the right proportions and they have additives such as hardeners and reducers. Water-based paints are simpler because they are ready to use right out of the bottle. They are convenient because you can put the paint straight into the spray gun and use it immediately. There is no complicated mixing involved.
Quick and Convenient
Urethane paints bind chemically as the different constituent materials meld together and fuse. Water-based colours bind mechanically, so the process is much faster. In addition to the time saved from not mixing the paint, water-based colours are convenient and fast. Sometimes you need to apply several coats of paint to the same car. When using urethane paints, you have to follow a strict time schedule between layers because trapped solvent may be released into the upper layers, causing 'solvent pop.' This problem is eliminated when using water-based paints.
When you paint a car using urethane paint, you might use a whole gallon of colour. However, when using water-based paint, two quarts are enough for the same job. This cuts down on costs. You also lower costs because you don't need a primer for water-based paints. You can spray the colour directly onto car surfaces made of aluminium, urethane plastic, fibreglass or metal. Also, unlike urethane paints, water-based paint does not spoil or dry out. You can leave paint in the spray can and use it months, or even years, later to avoid waste and save costs.
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