The Common Packaging Quality Issues and Solution XV

答：

Solution：

• Elemendorf tear test: using LTLD-1000Z film tearing tester, through the pendulum free hem to tear the pre-cut sample, by the computer control system to calculate the energy consumption of tear sample, get the tear force value (gf or mN). The longitudinal tear force of food vacuum packaging films is usually required to be ≥ 8 N. The test can be conducted by the tester LTLD-1000Z which follows the standard ASTM D1922, ASTM D1424, ASTM D689.(https://www.linktesting.org/835.html/elmendorf-tearing-tester-ltld-1000z/)
• Trousseau Tear and Right Angle Tear Test: Using the XLW-500N Intelligent Electronic Tensile Tester, equipped with special tear clamping fixtures, the plastic right-angle tear performance is tested according to QB/T 1130-1991 & ASTM F88 and the anti-tear ability of the film under complex stress directions is evaluated.

答：

The main reason is that the adhesive application in the composite process is uneven or has aged, resulting in insufficient interlayer bonding strength. Insufficient interlayer bonding strength is the direct cause of liquid leakage in food packaging and layer separation in medicine packaging bags.

Solution:

• type peel and parallel peel tests: Using the XLW-500  intelligent electronic tensile testing machine, equipped with anti-slip pneumatic fixtures, conduct T-type peel and parallel peel tests respectively, precisely measuring the interlayer peel force (N/15mm). Note that the new national standard GB/T 8808-2026 has added the "parallel peel" method and clearly requires the use of a 1st-level constant-speed testing machine in accordance with GB/T 17200-2008. The test can be conducted by the tensile tester XLW-500N(https://www.linktesting.org/7007.html/automatic-tensile-tester-xlw-500n/)

答：

The main reason is that the longitudinal and transverse shrinkage rates of the heat shrink film do not match or the shrinkage force is insufficient, resulting in the labels being unable to tightly wrap the bottle body.

Solution:

• Thermal shrinkage rate measurement: Using the LTRSY-03 thermal shrinkage tester, in accordance with GB/T 13519-2016 or ASTM D2732-14, the thermal shrinkage percentages of the film in the longitudinal and transverse directions within the temperature range of 100 to 200℃ are measured, with an accuracy of up to 0.1%.

Check the anisotropy ratio of the film (the difference in contraction values between the longitudinal and transverse directions), ensure that the longitudinal and transverse contraction rates match, and avoid wrinkling or curling of the label on curved areas such as the bottle shoulder and bottom. The test can be conducted by the shrinkage tester LTRSY-03(https://www.linktesting.org/2334.html/thermal-shrinkage-tester-ltrsy-03/)

答：

The sealing integrity is the most crucial physical barrier performance of flexible packaging.

Solution：

• Explosion-proof pressure test: Using packaging sealingity testing instrument, the positive pressure test principle is adopted. Air is charged and pressurized into the sealed packaging bag, and the bursting pressure of the entire bag (kPa) is measured. Various modes such as rupture test, creep test, and creep to rupture test are provided. The maximum test pressure can reach 1.6 MPa. The test can be conducted by the tester intelligent sealing tester LTMFY-06S(https://www.linktesting.org/1225.html/intelligent-sealing-instrument-mfy-06s/)
• Sealing leakage quantification determination: Using the leak tester, the negative pressure test principle is adopted. The vacuum chamber is evacuated to create an internal and external pressure difference in the immersed sample, observing the gas escape situation to determine the sealing performance. It complies with standards such as GB/T 15171 and ASTM D3078. The test can be conducted by the test leak tester LTY-01（https://www.linktesting.org/903.html/leakage-tester/）

答：

The compressive performance of soft packaging products is closely related to their sealing integrity. The stacking pressure is an important cause of the failure of soft packaging.

Solution：

• Packaging item compressive strength test: Using the packaging compressive strength tester, in accordance with standards such as ASTM D642 and ISO 12048, gradually apply pressure to the soft packaging items containing contents, and determine their yield pressure, maximum compressive load and permanent deformation rate. The test can be conducted by the carton compression tester KYJ-10K (https://www.linktesting.org/884.html/carton-compression-tester-kyj-10k/)
• Tensile strength assessment: Using the intelligent sealing tester, the burst strength and other indicators of the materials used in the flexible packaging bags are evaluated and analyzed to comprehensively determine the structural reliability of the packaging items under stacking conditions. The test can be conducted by the LTMFY-06S (https://www.linktesting.org/1225.html/intelligent-sealing-instrument-mfy-06s/)