Dr Voytek Gutowski, leader of the CSIRO team, with Mr Bill Matthews, Technical Manager of Dulux Powder Coatings.

Zero-waste coating process a real winner

CSIRO and Dulux Powder Coatings developed a coating system that's emission free and environmentally sustainable and it’s won a 2008 Premier’s Sustainability Award.

• 18 April 2008 | Updated 14 October 2011

• An industry problem
• A science problem
• Our solution
• Outcomes
• The award

The goal was to overcome a long term sustainability issue for the automotive, plastics and furniture industries by replacing wet paint finishes on heat-sensitive substances, such as plastic components, with zero-waste powder coating technology.

CSIRO joined with Dulux Powder Coatings and Sustainability Victoria to develop this technology which has won the 2008 Premier's Sustainability Award for products or services.

An industry problem

The Australian automotive industry uses about 10 million litres of liquid paint a year to coat the surfaces of new vehicles, including putting decorative finishes on plastic components such as:

• interior elements like door trim panels
• engine covers
• body parts
• bumper bars.

Traditional wet paints have disadvantages such as they:

• don’t have a high rate of spray transfer onto plastic parts (up to 70 per cent is lost as waste)
• contain solvents which release volatile organic chemicals (VOCs) to the atmosphere
• leave about 2.5 million litres of solid waste a year.

In Europe, emissions of VOCs from industry are strictly regulated. It is only a matter of time before similar restrictions are put in place here in Australia.

A science problem

Powder coating has many advantages, including:

• almost all the powder ends up on coated plastic components
• easy recycling of residual powder
• containing no solvents (therefore releasing no VOCs)
• no flash-off time after spray application (essential for removing residual solvent from wet paint)
• low reject rates (parts with imperfect coatings can be spotted before curing, the powder blown off and the part re-coated)
• easy clean-up.

Powder coating particles are attracted to and stick very well to the material being coated, providing it conducts electricity, like metal componenets.

Powder coating relies on the powder carrying one type of electrical charge and the material being coated having the other: opposite charges attract so the powder sticks and is then cured to form a smooth finish.

The plastics used to make the automotive components in questions are not conductive.

Our solution

Together with our partners, Dulux Powder Coatings/Orica, CSIRO developed the technology plaatform that enabled the replacement of wet paints with environmentally-friendly powder coatings when coating heat-sensitive substances such as plastics.

CSIRO achieved surface conductivity by coating the plastic components with a nanometre-thin layer of specialty multifunctional molecules that provide surface conductivity and promote the ability of the powder coating to stick well to plastic components.

Within this partnership, Dulux Powder Coatings developed new generation powder coatings that could be cured at much lower temperatures and for much shorter times than traditional powders.

Outcomes

This partnership resulted the development of technology that will:

• generate minimal waste
• minimise the release of harmful chemicals to the environment
• deliver significant savings in cost, electricity and greenhouse gas emissions.

The new powder coating system has been successfully trialled in the Australian state of Victoria and is now being customised for coating automotive plastics and is in demand by customers interstate and overseas.

The award

The Premier’s Sustainability Awards recognise businesses, communities and individuals in the Australian state of Victoria that demonstrate outstanding leadership and contribute to a more sustainable future.

Read about CSIRO's Hard coatings for automotive applications.