Natural soils on collars have been used to evaluate detergency and this is known as the most reliable method. However, quantitative measurements has not been made because of randomness of natural soils.
Recently we developed a new quantitative detergency evaluation method using an image analyser to replace the visual judgement. There is a linear relationship between the actual amount of soils and the degree determined by our equation based on Kubelka-Munks'. This method has a good correlation with the traditional visual judgement.