Food packaging bags are sometimes rejected by users because of peculiar smell, and the food inside is contaminated with bad odor and suffers compensation incidents. Many manufacturers feel a headache. What is the reason for the smell of food? Plastic bags Reasons for odor: 1. From printing ink and ink solvent or compound adhesive and compound adhesive. 2. Inner film from composite packaging. Processing methods of food packaging bags: 1. The design of the printing pattern should be selected from few colors and monochromatic elements, and try to avoid full-page printing patterns. 2. When selecting printing inks, do not use surface printing inks with strong odor. Do not use high-boiling solvents with impurities such as tar benzene, mixed benzene, recycled solvents. 3. Do not use one-component PS composite adhesive with high odor when compounding. 4. Select the inner layer film material when compounding, check whether it has odor, do not use PE film with filler as the inner layer substrate. 5. Try to improve the printing speed, reduce the viscosity of hard brush ink as much as possible, reduce the amount of ink, keep the drying box and workshop ventilated, and minimize the residual ink and ink solvent. 6. To keep the drying tunnel of the laminating machine smooth, the gluing should be appropriate, and do not use ester solvents containing impurities and moisture. The heating temperature of the laminating machine should be around 70 °C. 7. In the processing of food packaging bags, try to use films with good barrier properties as the inner layer material of composite packaging.