1. Printing quality:
See if there is an obvious third color at the splice of the two colors. The higher the level of realism in the physical image, the better. See if there are any phenomena such as brushing, fogging, blocking, and missing printing.
2. Materials for bags:
The packaging bag needs no odor. Smell bags generally make people feel that they do not meet the hygienic standards, and may affect the normal use of the bag. If there is no odor, you need to check the transparency of the bag, whether the clarity is uniform, whether there is a sense of impurities, etc.
3.坚定的包:
Bags made of bags are generally difficult to tear by hand. They can be used to hold heavier products such as stones and large particles. There are two main types of fastness, which are consistent with the firmness and hot air firmness. Wuxi aluminum foil bags have different levels of firmness due to different materials. The main distinguishing method is to align the edge of the bag and tear it by hand. Nylon and high-pressure film compound, etc., and the bags made of OPP heat sealing film are very easy to tear, and can only hold some light products; after the bag is torn, it depends on the shape and structure of the cross section. Even tearing in the middle indicates that the heat seal of the bag is very poor, and it is easy to break the bag during the production process; if it is torn from the edge, it means that the quality of the heat seal is better; it also depends on the composite firmness of the bag, the method is to first look at the crack There are several layers of structure at the place, and then see if you can separate it with your hands. If it is not easy to separate, it means that the composite has good firmness, and vice versa. In addition, the firmness of the bag should also be checked for bubbles or bubbles on the surface of the bag. Wrinkles, etc.
4. The uniformity of appearance:
First observe the stiffness of the bag. Generally, the higher the flatness, the better, except for different needs. For example, the bag made of nylon and high-pressure film will have a wave shape at the heat seal of the bag; you also need to observe whether the cut edge of the bag is neat, the more neat the better.