Home Industrial Paint & Coatings 101: Liquid Coating Basics
Liquid paints and coatings have two uses in industry: beautify and protect. When applied over a substrate, these materials enhance appearance and provide protection from harsh weather, severe environments, and daily use. There are countless formulations for coatings that allow customers to tailor their paint to meet their needs.
WHAT’S IN A LIQUID INDUSTRIAL COATING?
Understanding the key ingredients can help industrial coating buyers and users identify the best product for their project.
Paints and coatings have four primary ingredients:
• Resin/binder – the film-forming materials, also referred to as the vehicle of the coating. These ingredients hold the paint together and help it adhere to the substrate. The resin used is the key in all paint formulations when determining the level of protection offered by the coating.
• Water and solvents – the liquifying agents that can help disperse or dissolve other coating components. They thin the paint to required viscosities determined by the individual customer’s application requirements and equipment, while also assisting in the flow and leveling process. Although all liquid coatings contain water, solvent, or both, newer formulations are approaching (or have reached) zero VOCs (volatile organic compounds).
• Pigments – fine particles that add color, texture and protection properties.
• Additives – necessary to assist in the production process, they also provide specific performance enhancers, from corrosion resistance to drying agents, and can be tailored to the user’s needs.
When formulating paint and coating products, the primary ingredients are carefully manipulated and formulated to meet a customer’s specifications for cost, performance, application properties, protection, substrate, color, and environmental requirements.
WHAT ARE THE MOST COMMON TYPES OF INDUSTRIAL COATINGS?
There are many different types of coatings, each formulated to meet different needs. Coatings are broadly categorized as water- or solvent-based. (We’ll address more on the differences between water- and solvent-based coatings in a future article.)
The most common coatings include:
• Acrylics – known for their good adhesion, moderate corrosion resistance, and exceptional fade resistance.
• Alkyds – popular for their glossy finish, good-to-exceptional adhesion, high corrosion resistance, and general durability.
• Epoxies – used for their exceptional adhesion and durability against the weather, heat, and various chemicals, but typically not suited for protection from sun exposure without incorporating unique resins when formulating.
• Lacquers – popular for fast-drying, low-maintenance wood protection.
• Zinc-rich coatings – popular for application on steel to provide the highest level of corrosion protection.
• Urethanes – often used for their smooth and glossy finish, good abrasion resistance, and highest level of U.V. protection.
HOW ARE INDUSTRIAL COATINGS APPLIED?
The intended application method will depend on the size, complexity and type of substrate being covered. Application method is a critical consideration when determining the coating formulation.
The most common application methods for liquid coatings are:
• Spray – an air sprayer creates a mist of fine spray for a professional, smooth finish. Airless sprayers, which dispense the coating with greater pressure and efficiency, are used to cover large areas quickly with minimal waste.
• Dip – immersing a product directly into paint is an effective application method for products that need complete coverage.
• Flow – consists of several different application methods. In the automated spray method, evaporation control is used to ensure uniform application. It is ideal for coating items with complex detail and allows for a thinner application than dip coating. In curtain coating, streams of paint flow down through pipes or tubes in a “curtain” of paint that coats parts as they move through the flowing paint. In this method, the unused paint is collected and pumped back through to form a continuous curtain of paint as the process continues.
• Brush – commonly used for detail work.
• Roller – can be used efficiently on flat surfaces.
• Trowel – typically used for textured surfaces and to apply very viscous products such as coatings used on industrial smokestacks.
• Spin – uses centrifugal force to apply uniform coating coverage.
SHEBOYGAN PAINT COMPANY FORMULATIONS
At Sheboygan Paint Company, our scientists and technical experts work with each of our customers to formulate liquid coatings that precisely meet their needs. We carefully analyze application methods, desired protection properties, VOC and other requirements, performance characteristics, substrates, and operational conditions to create a coating that is just right. To learn more about how we can help with your industrial coating needs, please contact us at 800.773.7801.