Polyester powder coatings for indoor use MT-300

Surface Finish Options Overview

Product description

MT-300 is a series of polyester resin based thermo-setting powder coatings formulated using TGIC. The pigments used in the MT-300 series restrict the field of application of this powder coatings class to interior uses. MT-300 is designed for interior decoration such as, metal furniture, shop fittings, shelves, light fittings.

Powder properties

Pre-treatment

Galvanised steel requires surface preparation by either multi-stage pretreatment using either zinc phosphate or chromate conversion or controlled sweep blasting. Depending on the type of galvanizing, degassing or use of anti-bubbling additives may be required – follow the procedural advice of the pretreatment supplier. Iron phosphate and particularly Zinc phosphating of ferrous metals improves corrosion resistance. Aluminium substrates may require a chromate conversion coating.

Application

Powders can be applied by manual or automatic electrostatic spray equipment. A good protection is linked with the recommended film thickness. Bonded products have better application properties than blended products (more stable) but attention should still be paid to line settings in order to avoid “marble effect” and changes in aspect after recycling. Different substrates (aluminium, steel, galvanized steel…), use of primer, and big changes in film thickness may give a different aspect. Products with different codes should not be mixed even if same colour and gloss. It is recommended that for consistent application and appearance product be fluidized during application. MT-300 powder coatings can be applied by corona electrostatic or tribostatic equipment. However, the aspect obtained by tribo static equipment may vary when compared to electrostatic application and/or our color card.

Test conditions

Actual product performance will depend upon the circumstances under which the product is used. Testing has been determined under laboratory conditions using the following application properties and is for guidance only.

Mechanical tests

FAQ

1. What is Powder Coating?

Powder coating is a dry finishing process used to apply a protective and decorative coating on metal or other surfaces. Instead of using liquid paint, fine powder particles (usually made of polyester, epoxy, or hybrid resins) are electrostatically charged and sprayed onto a conductive surface. The coated object is then baked in an oven, where the powder melts, flows, and cures into a smooth, durable finish.

Key features:

Durable, hard finish

Resistant to scratches, corrosion, and UV

Environmentally friendly (no VOCs)

2. Benefits of Powder Coating

Powder coating offers several advantages over traditional liquid painting:

Durability: Resistant to chipping, scratching, fading, and wear.

Corrosion Protection: Provides excellent protection against rust and chemicals.

Environmentally Friendly: No volatile organic compounds (VOCs) and minimal waste.

Efficiency: Overspray can be collected and reused, up to 99% material utilization.

Uniform Finish: Smooth, even coating without runs or drips.

Cost-Effective: Single-coat systems can achieve high film thickness, reducing labor and energy.

Aesthetic Variety: Wide range of colors, textures, and effects.

3. What Temperature to Cure Powder Coating

The curing temperature depends on the type of powder used:

Epoxy powder: ~160–200°C (320–392°F)

Polyester powder: ~180–210°C (356–410°F)

Hybrid (Epoxy-Polyester) powder: ~180–200°C (356–392°F)

Typical curing time: 10–20 minutes depending on thickness and oven type.

Always follow the powder manufacturer’s specifications for best results.

4. Process for Powder Coating

The powder coating process usually follows these steps:

Surface Preparation:

Clean the surface thoroughly (remove oil, grease, rust, or dirt)

Methods: chemical cleaning, sandblasting, or phosphating

Pre-Treatment:

Apply a conversion coating or primer if needed to improve adhesion

Powder Application:

Spray the powder using an electrostatic spray gun or fluidized bed

Curing:

Bake the coated object in an oven at the recommended temperature for the powder type

The powder melts and forms a continuous, smooth film

Cooling & Inspection:

Let the coated item cool

Inspect for defects, uniform coverage, and desired thickness

5. How to Spray Powder Coat

Equipment Needed:

Electrostatic spray gun

Compressed air supply

Powder feed hopper or container

Grounding of the object

Steps:

Ground the object: Ensures the charged powder is attracted to the surface.

Spray evenly: Hold the gun 6–12 inches from the surface, moving in smooth, overlapping strokes.

Apply sufficient powder: Ensure full coverage without excessive buildup.

Cure immediately: Transfer the sprayed item to the curing oven to fuse the powder into a solid coating.

Tips:

Maintain consistent speed and distance while spraying.

Use proper ventilation to reduce airborne powder accumulation.

Test a small area to check film thickness and color before full application.