Overview
Leneta Form 3B Opacity Chart is a test paper specially designed for the paint, inks and other industries. Its size is 194 x 289 mm, and the Color style is white, medium black, and low white. The surface of the product is coated with sealed, which can effectively prevent the paint from penetrating into the interior of the cardboard and ensure the accuracy of the contrast ratio measurement and paint proofing results.
Features
1. The surface is coated with a seal to effectively prevent the penetration of the paint and ensure the accuracy of the test.
2. Specially designed for contrast ratio (hiding power) determination and paint proofing.
3. Standard Encasement, 250 sheets per box, easy to use and manage in the laboratory.
Principle
This Opacity Chart provides a contrast substrate for the determination of paint hiding power through its color block design of upper white, medium black, and lower white. The hiding power is calculated as: Y (reflection value in black area)/Y (reflection value in white area) * 100%. Spreader the paint evenly on the paper, and after drying, the hiding power of the paint can be objectively evaluated by measuring the difference in reflection value after film in black and white areas. 100% of the covering rate indicates complete covering, that is, there is no difference in black and white areas after film.
Applications
Paints, inks
Steps
1. Spreader the paint to be tested evenly on the Form 3B Opacity Chart according to the standard film steps.
2. Wait for the film to fully dry in the air.
3. Use professional instruments to measure the drying film, and the instrument will automatically calculate and display the hiding power value.
Notice
* Spreader coating should be uniform to obtain accurate test results.
Stir the paint evenly before testing and adjust it to a suitable temperature (e.g. 23 ° C).
* After filming, it needs to be placed horizontally until through drying.
* When performing dedicated tests such as levelling and sag, refer to the corresponding ASTM standard methods (such as ASTM D 4062, D4400) and match with special tools (such as levelling device, anti-sag device).
* Choose the appropriate scratch paper according to the color of the paint (e.g. Form WB for light Paints, Form 7B for dark paints).
The test paper can also be used for covering rate detection of transparent films and plastic products.
