Method for demonstrating cleansing efficacy

A method for displaying at least one of images or videos on visible display units for demonstrating cleansing efficacy of a personal care product or a component thereof, wherein the at least one of images or videos show the following process:

• (i) selecting a first portion of a porous article capable of allowing a gas to pass through its pores, wherein the porous article is connected to a source of said gas and immersed in a liquid while the source releases said gas which flows out of said pores to generate gas bubbles;
• (ii) treating the first portion of the porous article with contaminants;
• (iii) treating the first portion of the porous article with the personal care product or the component thereof;
• wherein a second portion of the porous article is selected in step (i);
• the second portion is also treated with contaminants in step (ii);
• and the second portion is treated with a comparative or placebo product in step (iii);
• and
• wherein following step (iii) the method comprises a step (iv) of assessing a change of the treated first portion relative to at least one of an untreated portion of the porous article or the treated second portion, the change is an amount of gas bubbles released from the porous article.