Leneta Test Charts

Metopac™ (Metal) Panels

Request Info		Painted Steel Panels for Measuring the Hiding Power of Powder Coatings and Industrial Enamels Black Surface: Solvent resistant, Non-bleeding, Reflectance - 1% maximum* White Surface: Solvent Resistant, Colour Retentive, Reflectance - 80% minimum* * Measured using ASTM Method E 1347
T12M T22M	Form No.  Colour  Area** Size T12G   Black & White 100 cm2 3 x 5-3/16 inch 76 x 132 mm T22G   Black 100 cm2 3 x 5-3/16 inch 76 x 132 mm T12M   Black & White 368 cm2 5-3/16 x 11 inch 132 x 279 mm T22M   Black 368 cm2 5-3/16 x 11 inch 132 x 279 mm **Allowing for 1/4" inch (6mm) hole.
T12G T22G

Major uses include:
ASTM Method D 6441 -- Measuring the Hiding Power of Powder Coatings -- A wedge shape film is applied on a T12G or T12M panel. Points of specified film thickness are located over the black and white areas, reflectances are measured and the mean contrast ratio at that film thickness is calculated. Alternatively, several black/white pairs of equal-thickness points at various film thicknesses are located, and the calculated contrast ratio plotted graphically against the film thickness to obtain the film thickness at a contrast ratio of 0.98. In this method the reflectance is measured with a small diameter aperture (e.g. 4 mm), and the film thickness with an electronic film thickness gage.

Powder Coatings Institute Method -- In this method the film thickness is determined directly on a T12G panel at 0.98 Contrast Ratio. Alternatively, the Contrast Ratio is determined at a specified film thickness. Reflectance and film thickness instrumentation are as in ASTM D 6441.

ASTM Method D 2805 -- Hiding Power of Paints by Reflectometry -- The film is applied uniformly over a T22G all black and a T12G black and white panel. The filmweight and reflectance R0 are determined on the all black panel, and the reflectivity Rof the coating determined on the black and white panel. The gravimetric spreading rate at 0.98 Contrast Ratio is then calculated using Kubelka-Munk equations. Conversion to volumetric spreading rate or to film thickness is readily accomplished.