ASTM D523 is a standard test method for specular gloss. It is a direct measurement taken with a “gloss meter”.  Typically measurements will be taken on a flat, homogeneous and clean surface.  The measurement can be taken on a small surface, i.e. 1 cm2 but it is preferable to use a larger surface and have more than one data point taken to ensure the sample’s surface is homogeneous and a representative result is reported.

Micom offers ASTM D523 Gloss testing services as part of its Surface Coatings testing offering.

Use and Factors to Be Considered

Specular gloss is used to measure the capacity of a surface to reflect more or less light.  This test method allows for 3 gloss meter geometries of 60, 20, and 85°, 60° being the most common one. 20° is a geometry used to measure high gloss value samples, i.e. above 70 units, whereas the 85° geometry is used to measure low gloss value samples i.e. values lower than 10 units.

Specular gloss measured per ASTM D523 is also impacted by specimen surface refractive index, the measured gloss ratings change as the surface refractive index changes. When evaluating products against a product specification, it is therefore important to consider that parameter as well.

Typical Experimental Parameters for ASTM D523 Gloss Testing

Number of specimens/product: 1 specimen, 10 readings
Specimen dimensions: 3” X 6”
Conditioning and testing Temperature: 23 ± 2 °C
Conditioning and testing relative humidity: 50 ± 5%

If you have any other questions about the ASTM D523 test or if you would like to speak to a testing professional at Micom Laboratories to discuss a custom test for your specific product, we invite you to contact us today. It will be our pleasure to talk to you and help you with the ASTM D523 test.

Other Related Test Methods

For additional test methods related to ASTM D523, we invite you to read more about Plastics testing, Material testing and ASTM testing.

Learn about the UV testing measurements before, during and after the test.

True Color Measurement

We also invite you to download our PDF on the true color measurement:

What is the difference between the “true” color of an item and its “perceived” color (by the human eye)?

Paint, Coating and Polymer Testing Services

We also invite you to download our brochure to learn more about our Paint, Coating and Polymer testing services.