Overview
The QHY type Buchholz Clearance tester is a SHIBO brand product, which is suitable for the Clearance test of single-layer films or multi-layer films of Paints and varnishes. The instrument forms the Clearance length by pressing the film, and the inverse function of the Clearance length represents the indentation resistance. When the film anti-indentation performance improves, the anti-indentation value increases.
Features
1. The total weight of the Crowd instrument is 1000 +/- 5g, and the payload is 500 +/- 5g to ensure the test accuracy.
2. Equipped with 20 times reading Microscope, with Illuminant incident angle greater than 60 °, reading accuracy of 0.1mm.
3. The structure includes a rectangular metal block, a hard tool steel sharp blade metal wheel, and two pointed feet, which are designed to be stable and durable.
Principle
The Cedar instrument applies a load on the film through the Cedar device to form the Cedar length, and uses the reading Microscope to measure the Cedar image length. The indentation resistance is calculated by the reciprocal of the Cedar length, which reflects the compression performance of the film.
Applications
Paints, varnishes single layer film, multi layer film
Standards
GB3186、GB9275—88
Steps
Prepare the test plate: ensure that the substrate is hard, flat, no distortion, the film is uniform, smooth and clean, and the film thickness is at least 10um.
2. sampling: according to the provisions of GB3186.
3. Board making: make a test board according to the requirements of Article 5 in GB9275-88.
4 environmental conditions: at a temperature of 23 +/- 2 ° C, relative humidity 50 +/- 5% conditions for testing.
5. Cellular determination: Place the test plate film up, place the Cellular device lightly in the appropriate position, contact the Cellular device after the foot first, place it for 30 +/- 1s and then lift it, first Cellular device and then leave the foot.
6.Measurement: within 35 +/- 5s after removing the Crowder, measure the length of the Crowder image with a Microscope, accurate to 0.1mm.
7. Sexual repeability test: Perform 5 tests in different parts of the same test plate and calculate the arithmetic average.
8. Calculate indentation resistance: After revising the average value, look up the table or calculate it through the formula 100/L.
Notice
• The substrate should be hard, flat, no distortion, and not deformed under test load.
• The film should exhibit plastic deformation rather than resilience deformation.
• Film Film thickness must be at least 10um.
• The film should be uniform, smooth and clean.
The test environment needs to strictly control the temperature and humidity.
• The order of placement and lifting of the Crowder should be correct.
• The measurement time window needs to be completed within 35 +/- 5s.
• The same test board requires multiple tests to be averaged.
