Powder Coated Aluminum Profiles for Window, Door and Curtain Wall Systems

We extrude, pretreat and powder coat aluminum architectural profiles in-house for high-performance window, door and curtain wall systems. The range covers outer frame and sash extrusions, mullions and transoms, thermal break sections with a PA66-GF25 polyamide barrier, glazing beads, sub-frames and coupling profiles. One supplier, one process chain, one color reference across every container shipped.

Send architectural CAD drawings and we manage the rest: custom die cutting, precision extrusion, multi-stage chemical pretreatment, automated electrostatic powder application, oven curing and laboratory testing. You choose the target RAL color, the texture finish and the durability grade, and we deliver profiles matched to your physical sample and consistent from the first container to the last.

The Reality of Architectural Coatings

Two suppliers can quote you powder coated aluminum windows. One uses a standard polyester resin that chalks and fades within three years facing direct sunlight. The other uses a super-durable resin that holds its gloss and color for fifteen years. Both look identical on day one. You find out which one you bought when the sun and the salt air have done their work.

The Resin Chemistry Drives UV Longevity

Powder coating is a dry plastic powder sprayed electrostatically onto aluminum and then baked at 180 to 200 °C. The powder melts, flows out into a continuous film and crosslinks into a hard coating that provides color, seals the metal from moisture and oxygen, and resists sunlight. How well it resists sunlight depends on the resin, because resin is the backbone of the formulation. If the resin breaks down under UV, the coating chalks, fades and eventually stops protecting the aluminum underneath.

We publish these as durability tiers rather than as a single number for all powder, because the coating on an interior partition door and the coating on a coastal curtain wall have nothing in common except the color. Matching the grade to the exposure is the difference between a frame that still looks new at year twelve and one that is being repainted at year four.

Pretreatment and Application

Coating adhesion depends more on pretreatment than on the powder. Profiles pass through a multi-stage chemical pretreatment that removes extrusion oils, etches the surface and builds a conversion layer for the powder to bond to. The powder is then applied electrostatically so it wraps the profile including the return flanges and the inside of the glazing groove, and the section is cured in an oven at 180 to 200 °C until the film is fully crosslinked. Coating thickness is typically 60 to 120 µm depending on the grade and the specification agreed, and the Qualicoat framework is used as the reference for coating quality on facade-grade work.

Thermal Break and System Profiles

Where the frame separates a conditioned interior from the weather outside, the metal path is interrupted by a PA66-GF25 polyamide strip that is crimped into knurled channels on both halves of the profile. Glass-fiber reinforcement gives the barrier the mechanical strength to carry shear between the inner and outer sections, while the polyamide itself conducts far less heat than aluminum does. That is what keeps the inner face warm enough to avoid condensation and stops the frame from acting as a radiator in winter.

Choosing a Grade for Your Project

• Interior partition and decorative trim: standard polyester, color and cost matter more than UV stability
• Residential windows and doors in temperate climates: weather-resistant polyester with UV stabilisers
• Exterior frames and curtain wall components: super-durable polyester for facade exposure
• Coastal, desert and high-altitude sites: PVDF powder where color retention over two decades is required

Standard length is 6.0 meters, minimum order quantity is 500 kg per profile, and profiles are packed in shrink film for protection during shipping. Tell us the exposure the frame will see, the color reference and the durability tier you are working to, and we will confirm the profile, the pretreatment sequence and the coating specification before production begins.