Determination method for gloss of paint film

This standard is applicable to the determination method of paint film gloss

This standard refers to GB1749-79 Determination of Gloss of Paint Films

Experimental term: Gloss, an optical property on the surface of a paint film, expressed by its ability to reflect light.

Experimental principle: Using a fixed angle gloss meter, the results are expressed as a percentage of the ratio of the amount of specular reflection from the paint film surface to the amount of specular reflection from the standard surface under the same conditions.

Experimental instrument: Glossmeter (WGG601) glass plate.

Experimental steps:

1. Use a film maker to prepare a paint film on a glass plate, and apply the clear varnish surface onto a pre prepared black matte glass plate. Thin coating uses 100 μ m, and self leveling uses 500 μ m. The paint film can be tested after 8 hours of film formation (or complete curing).

2. Connect the power supply and preheat for 10 minutes during the measurement. When detecting glossy paint films, place the measuring window of the instrument on a black standard plate. When detecting matte paint films, place the instrument on a white standard plate. The numerical display value is the standard plate value, indicating that the calibration function has been completed.

3. Place the instrument on the tested sample and read accurately to 0.1 °. Test three times at different locations.

Experimental results:

The difference between the count of each measurement point and the average value shall not exceed 5% of the average value, and the arithmetic mean of the readings from the three points shall be taken as the result.

After measuring five boards, calibrate them once with a standard board. The standard board should be wiped with mirror paper or velvet cloth to avoid damaging the mirror surface.