Types of Powder Coat

Linetec is a fully approved and licensed applicator of the leading manufacturers of high-performance powder coatings as well as polyesters, epoxys and acrylics.

There are two different types of powder coat - thermoplastic and thermoset. Thermoplastic powders melt and flow when heat is applied but they continue to have the same chemical composition once they cool and solidify.

They are generally applied to a surface that has been preheated to a temperature significantly higher than the melting point of the powder. As a thermoplastic powder material is applied to the hot surface it will melt and "fusion bond" to the surface and then "flow out" into a strong, continuous film. As the film cools it develops its physical properties. Nylon powder coating materials are the most commonly used thermoplastic powders.

Thermoset powder coatings also melt when exposed to heat, but they then chemically cross-link within themselves or with other reactive components. The cured coating then has a different chemical structure than the basic resin. Thermosetting coatings are heat-stable and, unlike thermoplastic powders, will not soften back to liquid phase when re-heated.

Thermosetting powders are derived from four generic types of resins: epoxy, acrylic, polyester and fluoropolymer. From these resin types, several coating systems are derived. Resins used in thermosetting powders can be ground into fine particles necessary for spray application and a thin film finish. Most of the technological advancements in recent years have been with thermosetting powders.

Thermosetting Powder Coatings

EPOXY resin is a hard, impact resistant interior only formulation. For the most part, epoxy coatings are used as functional coatings for substrate protection where corrosion resistance, impact resistance, and adhesion are essential. The primary limitation of epoxy-based coatings is poor weatherability. Typical applications include industrial equipments, automotive underbody components, metal furniture and appliances.

ACRYLIC resins are typically used in the automotive industry as a clear coat on materials. Acrylic creates a smooth clear coat with very good clarity and provides a hard surface that is highly chip-resistant. Acrylic resins are used as additives to promote improved flow and leveling as well as enhanced stain and chemical resistance in polyester hybrid, polyester TGIC, and polyurethane powder coatings.

POLYESTER powder coats are the most used of all powder coatings in the U.S. market. Polyester's offer a broad application field and many different chemistries including: Polyester/TGIC (triglycidyl isocyanurate); Polyester/TGIC-free; Super-durable Polyester and Polyester Hybrids. Some Super-durable and Hybrid Polyester resin systems meet the AAMA 2604 specification.

FLUOROPOLYMER resins are top of line for exterior weatherability and UV stability in both powder and liquid coatings. Fluoropolymer powder coatings are purposely tailored for the architectural market and offer a long-life durable finish. Fluoropolymer powder coat resin systems can be formulated to meet the requirements of the high performance AAMA 2605 specification.

Characteristics including color and gloss are utilized to determine how well a coating will withstand harsh environmental conditions. Coatings are tested by exposing test samples to the heat and humidity conditions of South Florida. The following paint types have been been proven to meet the corresponding architectural AAMA specification.

Paint Manufacturer AAMA 2603 AAMA 2604 AAMA 2605
Akzo Nobel Interpon D1000 and D1010 Interpon D2000 Interpon D3000
PPG     Duranar
Sherwin Williams   Powdura Super Durable TGIC & TGIC Free Sher-Nar
Spraylat   ARC 2001 Newlar
TCI   10000 Series 11000 Series
Tiger Drylac Series 29/17 Series 58/68 Series 75

Architectural Powder Coatings

2603 Powder Coat example

AAMA 2603

To meet the AAMA 2603 specification, powder coatings are most often formulated with standard durable polyester binder. AAMA 2603 is typically an interior specification, such as ceiling panels and supports and interior windows. 2603 powders offer good resistance to abrasion, scratching and scuffing, but should be applied where color retention is not required.

2604 Powder Coat example

AAMA 2604

AAMA 2604 is an "intermediate" specification. 2604 powder coatings are formulated with super durable or modified polyester resins. An ideal application for this paint would be balconies and railings where its toughness gives good resistance to wear. This finish will provide good color and gloss retention for approximately five years of exposure.

Two-tone painted extrusion

AAMA 2605

AAMA 2605 is the high-performance exterior specification. Depending on the manufacturer, a 2605 powder coat may or may not utilize a fluoropolymer resin (PVDF). These finishes are resistant to moisture, weathering, ozone and UV radiation. An application for this finish would include architectural projects that require long term cosmetic and functional protection.