What is Burnishing or Marring?

What is Burnishing or Marring?

“Marring” is the term commonly used to describe shiny patches or polished areas that become evident when painted surfaces have been subjected to abrasion, possibly caused by cleaning or scrubbing to remove dirt or stains.

Another term used to describe this same effect is “Burnishing“. The definitions provided by AS/NZS 2310 “Glossary of Paint and Painting Terms” are as follows:

1. Shiny or lustrous spots on a paint surface caused by rubbing the painted
2. The polished or glossy appearance on a surface produced by mechanical

The “Marring” effect is much more obvious with deeper, darker or more vibrant colours than it is with pastel shades and lighter colours, especially when the darker colours are selected for use on broad wall surfaces such as feature walls and accent areas.

The darker colours will tend to visually highlight any surface imperfections, especially when flat, matt or lower sheen level paints are selected.

Why does it occur?

When a conventional low sheen level paint surface is abraded (manual or mechanical) the microscopic roughness and jagged edges of the inert pigments that are present to impart the lower gloss become rounded. These rounded or worn pigment particles scatter light quite differently hence the abraded patch looks noticeably shiny or polished.

The darker the colour the lower the Light Reflectance Value (LRV). The combination of low LRV colours used in conjunction with low sheen level paint means less light is reflected (more is scattered) hence any surface abrasions & imperfections become more visible because they look shiny.

Changes in the appearance of dark coloured paint films can also occur after only mild rubbing with even a very soft non-abrasive cloth, tissue or even human skin contact. This change is not caused by any material being rubbed off the paint (not abrasive enough) but rather by material being rubbed onto the paint, thereby changing the way in which light interacts with the surface.

Flat sheen level paints will offer the greatest physical resistance (surface roughness) to mild rubbing thereby providing the greatest opportunity for any foreign materials to become lodged, retained or trapped in the hollows or low points in the microscopic surface texture, which in turn can be quite resistant to washing or rinsing away.

Deep colours are also more prone to “pigment transfer” (colour actually rubbing off) and subsequent surface marking, than lighter colours. This is an industry-wide issue relating to the very high level of coloured tinter being added to either clear base (no opacity) or extra bright base (very low opacity) in order to produce a paint that has adequate depth of colour and opacity or “hiding power”.

How does it occur?

The major factors that can lead to burnishing or marring on painted surfaces include;

• Use of deep, dark or vibrant colours in conjunction with flat or matt sheen level paints, especially in high traffic
• Use of low sheen level paints that are incapable of withstanding abrasion or abuse when applied to broadwall surfaces in high traffic
• Frequent washing and/or spot
• Using abrasive cleaning agents or tools (scourers) to wash or scrub painted
• Furniture or furnishings rubbing against the painted
• Use of lower quality paints that have poor scrub, stain and abrasion
• Use of low sheen level paints with very high tinter
• “Critical lighting” can also be a contributing factor as it will highlight any marring/burnishing that may be present.

The solution for burnishing

Whilst darker colours and low sheen level paints of average quality continue to be used in high traffic areas, the surface marking and cleaning difficulty will continue to be an ongoing problem.

Once the painted surface has experienced burnishing or marring it will be very difficult or almost impossible to remove the shiny patches by washing alone. These surface imperfections have become permanent ‘scars’ that will need to be eliminated by sectional repair and repainting of the affected areas.

Prevention  

To minimise or avoid burnishing or marring on existing painted surfaces, clean with a very soft damp cloth or sponge and non-abrasive cleansers, such as Ajax Spray ’n’ Wipe™; then rinse with clean water. The use of a stronger cleaning agent specifically designed for painted surfaces, such as Selleys® Original Sugar Soap, with a soft cloth will generally remove any stubborn grime and dirt build-up without the need for heavy surface abrasion.

This information has been sourced from Dulux Technical Advice on Burnishing or Marring