GB/T 47493-2026Sanitary paper products - Determination of the resilience of elastic components (English PDF)

7.1 Determination of elastic recovery performance under constant stress

7.1.1 Set the instrument's tensile and recovery speeds, initial clamping distance, and tensile constant force. A tensile and recovery speed of 100 mm/min is recommended, but other speeds may be used. Select other stretching and recovery speeds; the initial clamping distance can be selected according to the recommended values in Table 1, and the tensile constant force can be selected according to the recommended values in Table 2. Alternatively, other initial clamping distances and tensile force values can be selected based on the specific product conditions (such as different specifications) or by mutual agreement.

7.1.2 Take a sample and place it on the clamping device of the testing instrument. When testing the elastic waistband's tensile resilience at a constant force, for trousers... For diaper or feminine hygiene products, place the entire elastic waistband on the two clamping rods at both ends of the testing instrument, with the front end of the sample facing the test. For the sample placement, the sealing lines on both sides are positioned at the clamping rods at both ends, as shown in Figure

1.For waist-adhesive diapers, the back waist tabs are... The two end tabs (starting from the adhesive application point) are fixed to the two clamps of the testing instrument, and the sample clamping diagram is shown in Figure

2.Testing the elastic leg. When testing the elasticity of the diaper under tension, place the bottom of the leg opening of the pant-style diaper or feminine hygiene panty on the left (upper) clamping bar and the upper end on the right (lower) clamping bar. The sample is placed on the clamping rod, ensuring that the test area is the inner elastic component and not the leak-proof partition. A schematic diagram of the sample placement is shown in Figure

3.Horizontal rebound performance. The two clamping rods of the tester should be equipped with corresponding fixing devices to ensure that the sample is fixed and does not fall off after being placed.

7.1.3 After placing or clamping the sample, zero the force value, start the test, and pre-stretch one end of the sample until the force value reaches 0.3N pre-tension. At this time, the instrument automatically records the length L1 of the specimen between the two clamping devices. The specimen continues to be stretched until the force reaches the set constant force value, at which point the stretching stops. The tension is stopped and held for 30 seconds. The instrument automatically records the length L2 of the sample between the two clamping devices at this time. After 30 seconds, the clamping devices return to their initial positions. Set, pause for 30 seconds.

7.1.4 The instrument begins the reciprocating tensile test, with one end of the clamping device moving from the initial clamping distance (50mm, 100mm, or 180mm, etc.) to a displacement L2. The device reciprocates (stretch-recovery) between its positions three times. Based on the third recovery curve, the two clamps are read when the recovery force is 0.3N. The length L0 of the specimen between the two clamping devices, the restoring force (TP20) when the specimen is displaced between the two clamping devices by L2×80%, i.e., 20% effective recovery, and the specimen... The recovery force (TP30) is measured when the displacement between the two clamping devices is L2×70%, i.e., 30% of the effective recovery. The sample recovery force can also be read as needed. The restoring force at other displacements.

7.1.5 Report the tensile recovery force TP20, recovery force TP30, and elastic recovery rate of the specimen under constant force.

7.2 Determination of elastic recovery performance under constant elongation tension

7.2.1 Set the instrument's tensile and recovery speeds, initial clamping distance, and constant elongation value. The recommended tensile and recovery speed is 100 mm/min, but other values are also acceptable. Choose other tensile and recovery speeds; select the initial clamping distance according to the recommended values in Table 1, and the constant elongation can be selected according to the recommended values in Table 3, or according to... Depending on the specific product (e.g., different specifications) or by mutual agreement, other initial clamping distances and fixed elongation values may be selected.

7.2.2 Take a sample and place it on the clamping device of the testing instrument. When testing the elastic waistband's elastic recovery performance at a constant elongation, for trousers... For disposable diapers or feminine hygiene products, place the entire elastic waistband on the two clamping rods at both ends of the testing instrument, with the front of the sample facing the tester and the sides... The sealing line or adhesive joint is placed at the clamping rods at both ends, as shown in Figure 1; for waist-adhesive diapers, the back waist tab is placed... The two end tabs (starting from the adhesive application point) are fixed to the two clamps of the testing instrument, and the sample clamping diagram is shown in Figure

2.Elasticity test. When adjusting the leg circumference for stretching and rebound performance, place the bottom of the leg circumference of the pant-style diaper or feminine hygiene panty on the left (upper) clamping bar and the upper end on the right. (Below) On the clamping rod, ensure that the test area is the inner elastic component and not the leak-proof partition. The sample placement diagram is shown in Figure

3.Horizontal rebound The two clamping rods of the performance testing instrument should be equipped with corresponding fixing devices to ensure that the sample is fixed and does not fall off after being placed.

7.2.3 After the sample is placed or clamped, the force value is zeroed, the test is started, and one end of the sample is pre-stretched until the force value reaches 0.3N pre-tension. At this time, the instrument automatically records the length L4 of the specimen between the two clamping devices. The specimen continues to be stretched until the length of the specimen between the two clamping devices reaches... When the elongation is set to L5, stop stretching and hold for 30 seconds. Then, return the clamping device to its initial position and hold for another 30 seconds. Example. If a constant elongation of 100% is used, then L5 = 2L4; if a constant elongation of 50% is used, then L5 = 1.5L4.

7.2.4 Begin the reciprocating tensile test, with one end of the clamping device moving from the initial clamping distance (50mm, 100mm, or 180mm, etc.) to a displacement L5. The device reciprocates (stretch-recovery) between its positions three times. Based on the third recovery curve, the two clamps are read when the recovery force is 0.3N. The length L3 of the specimen and the restoring force when the specimen is displaced between the two clamping devices by L5 × 80%, i.e., 20% of its effective recovery position. (TP20), the restoring force (TP30) when the specimen is displaced by L5×70% (30%) between the two clamping devices and effectively returns to its original position. (TP20) Yes, it is also possible to read the restoring force when the sample returns to its position at other displacements.

7.2.5 Report the elongation recovery force TP20, recovery force TP30, and elastic recovery rate of the specimen respectively.

8.2 Resilience

8.2.1 Elastic waistline recovery force Three specimens were tested for each sample, and the arithmetic mean of the recovery force TP20 and recovery force TP30 of the three specimens was expressed as the result. The result is expressed in Newtons (N) and is rounded to two decimal places.

8.2.2 Elastic leg circumference recovery force For each sample of diapers and feminine hygiene pants, three pieces were tested. The elastic leg circumference of each sample was tested separately on both the left and right sides, with three tests conducted on each side. Each sample yielded a total of 6 valid test results. Test results can be reported individually for each side or as a whole for both sides. (The last sentence appears to be incomplete and possibly refers to a separate test.) The arithmetic mean of the three recovery force TP20 and recovery force TP30 test values represents the test result for each side. The result is expressed as the sum of the six recovery force TP20 and recovery force values. The arithmetic mean of the TP30 test values represents the overall test result of the sample, expressed in Newtons (N), and the result is rounded to two decimal places.