After the coating is cured, use scissors to cut the PET film into 3x3cm samples for water contact angle and light transmittance haze test; cut the PET film into 10>x30cm samples for adhesion, coating film flexibility, wet abrasion resistance Performance testing .
Adhesion tests were performed on the samples using the cross-hatch standard in ASTM D3359. Cut the surface of the sample with a scribe with 11 blades and a distance between blades of 1 mm under sufficient lighting conditions. During the cutting process , all cutting angles should be consistent, the cutting pressure should be uniform, and it is necessary to ensure that the blade completely cuts the coating and touches the PET substrate. Carry out a second cut of the sample in a direction perpendicular to the direction of the first cut. After cutting, brush off the paint film , paste it on the cross grid on the paint film with 600-type 3M adhesive tape, and flatten it with your fingers to ensure good contact. After 30s, pull down the tape slowly at an angle of 180 degrees at a constant speed, and check the peeling of the paint film from the substrate in the grid area. The knife edge is smooth and has no falling off, which is grade 5B; the number of missing grids is less than 5 grids, which is grade 4B; the number of falling grids is 5-15 grids, which is grade 3B ; 35-65 grids are recorded as IB grade; the number of missing grids is more than 65 grids is recorded as 0B grade. The small cell with a fall-off area greater than 50% is calculated as l cell. Each sample was replicated at least in different regions.
