Quality inspection method of pharmaceutical aluminum foil gravure material
The quality requirements for printing on the surface of pharma aluminum foil are: the printed text and pattern are clear and firm, and after high temperature heat sealing, the text and pattern are still clear and do not change color. The bonding fastness of the printed text and the aluminum foil is generally identified by the adhesion fastness of the ink and the initial drying of the ink. The test method of adhesion fastness is: when the surface wetting ability of aluminum foil is 32-38x1O -5 N/cm, the general gravure method is used to print the ink, or the copper rod with a diameter of 9 mm is wrapped with a steel wire with a diameter of 0.12 mm. Scrape the ink on the aluminum foil with a scraper. After the printing sample is placed for 24 hours, stick an adhesive tape on the ink, and roll it back and forth on the adhesive tape rolling machine for 3 times. The speed of .Om/s peels off the adhesive tape.
At this time, the ink layer may be adhered to the adhesive tape and peeled off. Cover the tested part with translucent millimeter lattice paper with a width of 20 mm, count the number of lattices occupied by the area where the ink layer is intact, and then count the number of lattices occupied by the area where the ink has been removed, use A=A 1 / ( A 1 +A 2 ) x100% Calculate the adhesion fastness of the ink. In the formula: A is the area percentage of the adhesion fastness of the ink, A1 is the grid number of the intact ink layer after the test, and A2 is the grid number of the ink layer removed after the test. The adhesion fastness of qualified ink should be greater than 90%. Test method for the initial drying performance of ink: The initial drying performance of ink refers to the ink under certain temperature (25 ± l ℃), certain humidity (65 ± 5%) and certain time (30S) conditions, due to the volatilization of the solvent, The ink layers of different thicknesses initially achieve dryness from liquid to solid.
Test method: Prepare a clean squeegee fineness tester. Under the above temperature and humidity conditions, use a glass rod to pick up the ink and quickly drop it on the top 100um of the squeegee fineness tester. Fill the entire groove from 1OOum to zero of different thicknesses. Immediately press the stopwatch to time, when the time reaches 30S, press the 65g/m 2 drawing newspaper with a length of 160 mm and a width of 60 mm on the bottom end of the scraper fineness meter to cover all the grooves of the scraper. A 50-degree rubber roller rolls on the paper from bottom to top.
Uncover the paper, a certain amount of ink will stick to the paper at this time, the thin layer of ink may be dry and will not stick to the paper, and the thick layer will stick to the paper when it is dry. From zero, measure the length of the unstained ink in millimeters, and express the initial dryness of the ink in mm/30S.
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