The unwind strength of packaging adhesive tape can be determined using the following method:
Unwinding test method: fix the adhesive tape tightly on one end, and hang the other end on a suspension device, then gradually increase the weight, record the minimum required weight, and this weight is the unwinding strength. The test can be performed at a certain speed to measure the unwinding strength of the adhesive tape.
Hanging ball method: Hang a ball of known weight on one end of the adhesive tape, and then gradually move the ball down until the adhesive tape is unwound. Record the mass of the ball, this mass is the unwinding strength.
Hanging weight method: Fix the adhesive tape tightly at one end and hang the other end on a suspension device, then hang a weight of known weight on the adhesive tape, and record that the adhesive tape begins to unravel. The mass of the weight when rolling, this mass is the unwinding strength.
Here are the specific steps for each method:
Unwinding test method:
Prepare a length of adhesive tape and fasten one end to the test machine and the other end to a hanging device.
Gradually increase the weight of the suspension until the tape begins to unwind.
Record the minimum weight required and calculate the unwind strength of the tape based on the selected test conditions.
Hanging ball method:
Prepare a length of adhesive tape and fasten one end to the test machine and the other end to a hanging device.
Hang a ball of known weight from the other end of the tape.
Gradually move the ball down until the tape begins to unwind.
Record the mass of the ball and calculate the unwind strength of the adhesive tape according to the selected test conditions.
Hanging weight method:
Prepare a length of adhesive tape and fasten one end to the test machine and the other end to a hanging device.
Suspend a weight of known weight from the other end of the tape.
Gradually increase the weight of the suspension until the tape begins to unwind.
Record the mass of the weight when the adhesive tape begins to unwind, and calculate the unwinding strength of the adhesive tape according to the selected test conditions.
In conclusion, different test methods can be used for different types of adhesive tapes, and attention should be paid to the accuracy and consistency of operation during testing to ensure the accuracy and repeatability of test results. At the same time, according to the type and application scenario of the specific adhesive tape, a suitable test method can be selected.