the reason:
(1) The heat sealing temperature is too high;
(2) Excessive pressure;
(3) The hot air time is too long;
(4) The edge of the upper sealer is too sharp or the coated PTFE is damaged;
(5) The silicone rubber at the bottom seal is too hard;
(6) During the compounding and curing process, part of the adhesive penetrates into the film. Due to the penetration of the adhesive, the toughness (impact resistance) of the substrate has decreased and the brittleness has increased;
(7) After the plastic composite packaging bag is cooled and placed, the heat-seal strength is enhanced, and it also tends to become brittle.
     Countermeasures:
(1) According to the heat sealing characteristics of the material of the inner sealing layer, select the appropriate processing temperature, pressure and heat sealing time;
(2) Improve the surface condition of the upper heat sealing knife and make the surface of the sealer flat;
(3) The coating is intact with PTFE;

(4) Choose a silicone rubber pad with appropriate hardness.