Source：Link Testing Instruments Co.,Ltd
What is the reason for the ink layer peeling of medicinal aluminum foil?
Quality issues:
The ink layer peeled off on the aluminum foil surface of the drug blister pack.
Cause Analysis:
--Packaging material
• The adhesion or heat resistance of the aluminum foil protective layer is poor-the protective layer on the aluminum foil surface can not only prevent oxidation and corrosion of the aluminum foil, but also protect the printed layer on the aluminum foil surface from being rubbed. If the adhesion of the protective layer is poor or the heat resistance is poor, when peeling occurs during heat sealing or other heating processes, the protective effect of the ink will be weakened, so the ink layer is prone to be rubbed off and peeled off. It can be verified by the protective layer adhesion and protective layer heat resistance test.
• Improper control of the printing process-If the printing process is improper, it is easy to cause the adhesion and strength of the ink on the surface of the aluminum foil to decrease. After the protective layer is missing, the ink is prone to fraying or falling off.
Expert advice:
—— Pay attention to the monitoring of the adhesiveness of the protective layer of medical aluminum foil and the heat resistance of the protective layer.
——Adjust the printing process appropriately.
Typical quality case:
——Test sample: Analgesic tablets blister pack (customers report that the handwriting printed on the aluminum foil surface of the blister pack is easy to be rubbed).
——Targeted testing items: adhesion of protective layer, heat resistance of protective layer.
——Test result: In the protective layer adhesion test, the protective layer of the aluminum foil did not fall off, but in the thermal resistance test of the protective layer, the protective layer fell off significantly. Therefore, the heat resistance of the protective layer is poor, and the protective layer is easy to fall off during heat sealing or other high-temperature links, which is the main reason that the printed handwriting is easy to be rubbed.
Why does blister packaging have the problem of low heat sealing strength?
Quality issues:
The combination of PVC rigid board and medicinal aluminum foil to form a blister package has low heat sealing strength.
Cause Analysis:
(1) Packaging materials
• Adhesive and aluminum foil have poor adhesion-the rigid sheet and medical aluminum foil are bonded together by an adhesive. If the adhesive has poor adhesion on the surface of the aluminum foil, it will be heat-sealed with the rigid sheet. When damaged by external force, the adhesive is easy to fall off from the surface of the aluminum foil, resulting in low heat sealing strength.
• The uniformity of the adhesive distribution on the aluminum foil surface is poor-improper selection of the adhesive or improper control of the adhesive coating process will easily lead to poor uniformity of the adhesive distribution on the aluminum foil surface, which will affect The heat-sealing strength between the rigid sheet and the aluminum foil. It can be verified by the difference test of adhesive coating amount.
(2) Finished product packaging process
• Improper setting of heat-sealing process parameters-if the process parameters of the heat-sealing equipment are not set properly, the infiltration state of the adhesive on the surface of the hard sheet is poor, or the bubbles between the hard sheet and the aluminum foil are not driven out, the blister packaging is difficult Achieve the ideal heat sealing strength. It can be verified by heat sealing strength test.
Expert advice:
——Pay attention to the monitoring of aluminum foil's adhesive coating amount difference, heat sealing strength and other properties.
——Choose an appropriate adhesive and adjust the coating process and heat sealing process parameters of the adhesive appropriately.
Typical quality case:
——Test sample: Cold capsule blister packaging (the customer reported that the heat sealing strength of the blister packaging is low, and the surrounding heat sealing parts will be destroyed when the capsule is pushed).
——Targeted test items: heat sealing strength.
——Test results: The heat-sealing strength is only about 5.1 N/15mm, which is far lower than the heat-sealing strength value required in YBB00152002 "Aluminum Foil for Pharmaceutical Packaging". Such a low heat sealing strength can easily lead to poor airtightness of the blisters where the remaining capsules in the blister pack are located, and the amount of moisture and oxygen contacted increases, which is prone to oxidative deterioration.
What is the cause of the leakage of the aluminum-plastic composite ointment tube?
Quality issues:
The aluminum-plastic composite ointment tube leaks when it is squeezed by an external force.
Cause Analysis:
(1) Packaging materials
• Poor toughness of aluminum-plastic composite material-if the quality of the aluminum-plastic composite material used in the production of the ointment tube is poor, the toughness is low, the resistance to flexing, and the folding are poor, and pinholes are likely to occur during the filling of the paste or the consumer's use A slight defect or breakage may cause leakage of the ointment tube. It can be verified by tensile strength and compressive strength tests.
(2) Finished product packaging process
• Poor heat sealing effect-If the heat sealing quality of the heat sealing part of the aluminum-plastic composite ointment tube is poor, it is easy to leak at the heat sealing part when it is squeezed by force. It can be verified by heat sealing strength of tube body, heat sealing strength of tube tail, and compressive strength test.
• Poor adhesion between the tube head and the tube cap-if the aluminum-plastic ointment tube head and the tube cap have poor compatibility and poor sealing, leakage problems will easily occur at the junction of the tube head and the tube cap. It can be verified by compressive strength and airtightness tests.
Expert advice:
——Pay attention to the monitoring of the tensile strength, compressive strength, heat-sealing strength of the tube body, heat-sealing strength of the tube tail, and airtightness of the aluminum-plastic composite ointment tube.
Typical quality case:
——Test sample: an anti-inflammatory aluminum-plastic composite ointment tube (customers report that the product is prone to leak at the nozzle).
——Targeted testing items: compressive strength and airtightness.
——Test results: In the compressive strength test, the product leaked air at the nozzle; in the tightness test, water leaked slowly at the nozzle. Therefore, the poor adhesion between the nozzle and the cap of the aluminum-plastic composite ointment is the main reason for the leakage of the nozzle.
How to solve the problem of delamination in the sealing part of the plastic composite film packaging after heat sealing?
Quality issues:
Some flexible plastic composite film packaging (such as aluminum-plated composite film) has the phenomenon of material delamination in the sealing part after heat sealing, that is, the separation of each layer in the composite film.
Cause Analysis:
--Packaging material
• Poor peel strength-due to factors such as too low or too thick adhesive coating and uneven coating, the composite film has poor composite fastness between each layer of the film, compared to the seal with higher heat sealing strength , Prone to stratification.
• Adhesives and inks are of poor quality—if the adhesives used as the composite film of the packaging bag and the inks used for external printing of the packaging are of poor quality and are not resistant to high temperatures, they will easily lead to high temperature heat sealing. The bonding effect (ie, composite fastness) of each single-layer film of the composite film is reduced, and the composite film is prone to delamination.
Expert advice:
—— Pay attention to the monitoring of the main performance of packaging such as peel strength (empty packaging bag or roll film), heat seal strength and so on.
——According to factors such as heat-sealing temperature, drug characteristics, etc., select suitable adhesives and inks, and control the adhesive coating process.
Typical quality case:
——Test sample: aluminum-plastic composite film packaging used for packaging drug particles (a cold granule manufacturer reported that its finished packaging bags were layered at the seal).
—— Targeted testing items: peel strength (empty packaging bag), heat seal strength.
——Test results: The peeling strength of the empty packaging bag is 2.8 N/15mm, and the heat sealing strength is 21.03 N/15mm. The results show that the peeling strength of the empty packaging bag is lower. Compared with the higher heat sealing strength, it is easy to be in the later stage. Delamination occurs during use. It is recommended to reasonably improve the coating amount of the adhesive between each layer of the composite film, improve the adhesion between the adhesive and each layer of the film, and use high temperature resistant adhesive components.
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