PTc gloss meters are used to quantitatively assess surface luster or brightness often defined as specular reflection gloss.In addition to smoothness, variation in type and thickness of the coating greatly influences brightness.
The PG60 (60° single) and the PGM (20, 60 and 85° tri-gloss combination) gloss meters are our standard models. Additional single-degree models are also available on a special order basis: PG20, PG45, PG75 and PG85.
To measure gloss, a beam of light of fixed intensity is projected at a fixed angle onto the subject surface and measuring the amount of light reflected at an equal and opposite angle. Measurement angle refers to the angle formed between the beams of incident and reflected light. Angle selection is based upon the type of surface being measured. The choice of the measuring angle is critical in order to obtain a clear differentiation over the complete measurement range from high gloss to matte finish.
All levels of gloss may be measured at the universal measurement angle of 60°. If the result indicates low gloss or matte finish (≤ 10 GU), a subsequent measurement at 85°is called for. Similarly, if the result of the 60°test is high gloss (≥70GU), a 20° measurement should be undertaken.
Gloss meters and their operating procedures are internationally specified to allow comparison of measurement values. PortableTesters.com LLC offers the PG series gloss meters which are designed and manufactured according to international standards ASTMD523, ISO2813, and DIN67530.