METHODS OF TEST FOR PAINTS AND VARNISHES : PART D4 : COMPARISON OF CONTRAST RATIO (HIDING POWER) OF PAINTS OF THE SAME TYPE AND COLOUR (FIRST REVISION) [ISO 2814 : 1973, MOD]
This Malaysian Standard specifies the standard method to be used in comparing the contrastratios given by paint films of white or light colours, of reflectance factor greater than 40 %,dried at normal air temperatures and applied at approximately equal wet film thickness to black and white substrates.
The method, comparison of contrast ratio of films drawn down on a black and white substrateat equal wet film thickness, is the simplest of those investigated and has been found to give are producible comparison for paints of similar type. Because different operators using the same film coating device obtain films differing significantly in thickness, probably due tovariation in pressure on the applicator, the method is not satisfactory as an absolute method for the determination of hiding power. Alternative techniques for test film preparation and measurement are specified; MS 133 : Part D6 deals with application to black and white charts, while MS 133 : Part D7 deals with application to
