Printing solvent for food packing bag
Look at the appearance of the solvent. Should be clear and transparent, if there are cloudy and floating objects, the batch of solvents should be used with caution.
Smell the smell of solvents. Contact with commonly used solvents, smell, after a long time, the odor of a particular solvent has a rough impression. If the odor of the batch solvent is not pure, it is certain that the purity of the batch solvent is not high or the impurities are more. In addition, the solvent is applied to a clean plastic film to compare its basic odor before and after volatilization, and the tendency of residual solvents can be roughly judged.
Use a moisture indicator to determine the content in the solvent. The water indicator is put into the solvent, and the water content varies with different colors. Depending on the color change, the amount of water in the solvent can be roughly determined.
Determine the amount of water in the solvent by means of the principle of a different dissolution effect. Take the most transparent glass cylinder tube with 100ml toluene solution, take a small amount of analyte ester solvent such as toluene, evenly pour. When you just pour in toluene, carefully observe whether there is turbidity (milk white) phenomenon. If there is this phenomenon, the water content of the solvent is seriously exceeded, and the experience shows that when the moisture content exceeds 0.5%, the phenomenon is obvious. The water content test of benzene solvent can be carried out by extracting solvent from the long glass tube to observe whether there is delamination.
