The contents of conventional physical and chemical tests are as following:
(1) Appearance tests are mainly performed with the naked eye. That is, the front and back of printed tinplate products require no obvious dirt and wrinkles. There are no obvious scratches on the main parts of the printing surface. Minor scratches are allowed on minor areas. The text lines are clear and complete without distortion, and the dots are clear, complete, layered, and the ink color is uniform and accurate.
(II) Physical and chemical indicators.Physical and chemical indicators include: impact resistance, adhesion, gloss, whiteness, ink layer surface hardness, cooking resistance, overprint, etc. In addition, there are special requirements such as sulfur resistance test, acid resistance test, etc. Additional inspections in addition to the above-mentioned routine inspections. Mainly according to the special needs of the product. Add some necessary testing items. For example, when printing ham cans. For printed tinplate products, items of anti-sulfur test and high temperature sterilization test shall be added. for printed board products, additional writing inspection items shall be added.