The sealing performance of plastic bags is usually ensured by the following methods:
 

Material selection: Choosing a material with good sealing performance is the key to ensuring the sealing performance of the plastic bag. Commonly used materials such as polyethylene (PE) and polypropylene (PP) usually have better sealing properties. These materials can quickly fuse together to form a seal when heated or pressure is applied.

Sealing method: The sealing methods of plastic bags usually include heat sealing, pressure sealing, zipper, etc. Heat sealing is the most commonly used method, where the material of the plastic bag melts and bonds together by heating the sealing area. Pressure sealing is the application of pressure to press the openings of the plastic bag together to form a seal. The zipper closes the mouth of the plastic bag by pulling the zipper to achieve a seal.

Sealing temperature and time control: For heat sealing methods, it is very important to control the sealing temperature and time. Too high temperature and too long sealing time may cause the material to over-melt or burn, affecting the sealing performance. Therefore, according to the characteristics of the plastic bag material, the sealing temperature and time need to be accurately controlled to ensure a good seal.

Application notes