Some plastic packaging bags have a pungent odor before use, and even the food packaged in them may have a similar odor. The specific reasons are analyzed as follows:1. Improper printing process control – This results in insufficient evaporation of organic solvents (alcohols, ketones, esters, benzenes, etc.) used to dissolve the printing inks. Solvent residue testing can be used to determine the total amount of residual solvent and verify the presence of harmful benzene compounds.2. Improper lamination process control – This results in insufficient evaporation of organic solvents used to dissolve the adhesives during the lamination of the packaging film.3. Poor raw material quality – The resin raw materials used to produce the packaging materials themselves, or the small molecule substances with odors added to them, contain a high content.4. Poor adhesive quality – The adhesives used to laminate the various film layers produce harmful substances such as toluene diamine at high temperatures.

Taisheng Packaging suggests the following:First, attention should be paid to monitoring hygiene performance indicators such as solvent residue, evaporation residue, toluene diamine content, and potassium permanganate consumption.Secondly, it is necessary to select suitable inks (such as solvent-free inks) and adhesives, and adjust the evaporation and drying process parameters during printing and lamination.