Transparent plastics—Transmissivity and haze test methods
This method is applicable to determination of the transmissivity and haze of plate-like, sheet-like and thin-film transparent plastics.
I. Definitions
1. Transmissivity——ratio of the luminous flux of light through the specimen to that on the specimen, expressed as a percentage
2. Haze——ratio of the luminous flux of scattered light deviated from the direction of incident light through the specimen to that of transmitted light, expressed as a percentage (for this method, only the luminous flux of scattered light more than 2.5 degrees from the direction of the incident light is used to calculate haze)
II. Significance
3. The method can be used to control products and study some optical properties of products.
4. Transparent plastics can be compared in terms of transmissivity and haze only if they are in the same thickness.
III. Specimens
5. Specimen size: 50×50mm; original thickness.
6. Specimens shall be uniform, free of blister; two measuring surfaces shall be smooth and parallel, free of scratches, foreign matters, oil stains, etc. Unless there are special requirements, specimens may conform to the requirements of product standards.
7. There shall be at least 3 specimens of each group.
8. Generally, specimens are not subjected to preconditioning; in special cases, they are preconditioned before tests according to product standards or conditions agreed by the seller and the buyer.
IV. Test conditions
9. Temperature: 23±5°C; relative humidity: 50±20%.
I. Definitions
II. Significance
III. Specimens
IV. Test conditions
V. Test apparatus
VI. Test procedures
VII. Calculation and expression of test results
VIII. Test report
