Fault phenomenon Phenomenon Solution Bubbles appear on the composite membrane The drying tunnel temperature is too low, leaving residual solvent â— Improve the drying tunnel, adjust air volume and wind speed Solvent moisture content is too high â—Control solvent content is less than 0.2% Environmental humidity is too high â— Keep the environment ventilated and dry Composite film wrinkles Uncoordinated winding or unwinding tension, too big or too small â— Adjust the closing and unwinding tension Composite roll pressure imbalance or uneven pressure â— Adjust the composite roll to balance it Composite roller filling or guide roller imbalance â— Adjust the compound roll or adjust the balance of seek roll Composite film has white spots Humidity in the environment or the solvent is too high â— Control environment humidity and solvent moisture content Too much residual solvent â— Increase the temperature of the drying tunnel or slow down the speed Stirring unevenly when using adhesive â— When mixing, stir well Excessive amount of curing agent â— Reduce the amount of curing agent There is still stickiness after the composite film matures With wrong glue or uneven mixing with glue â— Correctly grasp the use conditions and process of adhesives Humidity of the environment is too high, the solvent has too high water content â— Control environment humidity and solvent moisture content Incomplete curing â— Increase the curing temperature or extend the curing time The quality of the glue itself â— Replace glue Composite film peel strength is low Insufficient glue â— increase the concentration of work and replace the roller Film is damp or corona treated â— Exchange film or corona treatment Incomplete curing â— Prolong the curing time appropriately Solvent water content is too high to misalign the base agent with the curing agent â— control solvent water content less than 0.2% Bags produce odor Drying temperature is too low, residual solvent is too much â— Improve drying tunnel temperature and increase air flow rate and wind speed Dilution solvent contains aromatic impurities (toluene, xylene) â— Improve the purity of the solvent Additive odor in the film â—Change film The ink is not completely dry during printing. â— Rewind the printed film once through the tunnel Adhesives contain aromatic solvents â— Replace glue Low heat seal strength The quality of the adhesive itself â—Change adhesive Adhesive curing dose is too small â— increase the amount of curing agent The humidity is too high or the solvent has too high water content â— Control environment humidity and solvent moisture content Composite film is not matured â—Prolong the curing time Source: Huashi Chemicals
Residual high-boiling solvents
Polyurethane Adhesive Dry Composite Failure and Treatment