Test method for adhesive strength of ointment sticking

Test method for adhesive strength of ointment sticking

I. Pharmacopoeia Standard Testing Method (Chapter 0952 Adhesion Force Determination in Chinese Pharmacopoeia 2025)

Testing Equipment

Adhesive Retention Tester: Composed of a test frame, test plate, weight loading device, and displacement measurement system, requiring stainless steel material and precision specifications.

Environmental Control: The lab must maintain stable temperature (18-25℃) and humidity (40%-70%).

Testing Procedure

Sample Preparation: Cut adhesive patches to standard size and fix the backing to the test plate with double-sided tape, ensuring no air bubbles.

Weight Loading: Hang a specified weight (e.g., 1kg) at the free end to apply vertical tension.

Displacement Monitoring: Record the sliding distance (pharmacopoeia requirement: ≤2.5mm) or complete detachment time.

Judgment Criteria

Qualified adhesive patches should maintain adhesion during the test period (typically 1-24 hours) without exceeding displacement limits.

II. Industry-Expanded Testing Methods

Dynamic Adhesion Test

Simulates joint movement scenarios, periodically stretching adhesive patches with a robotic arm to assess peel resistance.

Applicable Instrument: Electronic tensile tester (e.g., MTL-01).

Damp-Heat Aging Test

Accelerate aging of adhesive patches in a 40℃/75%RH environment and test changes in adhesive retention after aging.

III. Key Considerations

Sample Pre-Treatment: Balance samples in a standard environment for over 2 hours before testing.

Cleaning Requirements: Clean test and loading plates repeatedly with anhydrous ethanol until free of contaminants.

Repeatability Verification: Test each sample group three times and average the results to improve data reliability.

ST107 Retention adhesion tester is designed and manufactured strictly in accordance with the requirements of the new 2020 Chinese Pharmacopoeia "0952 Adhesion Force Determination Method", and is suitable for conducting adhesion testing on products such as ointments.

Working principle: Hang the test plate with the sample vertically on the test frame, hang a weight of the specified weight at the lower end, and measure the resistance of the adhesive tape to detachment by the displacement of the sample after a certain period of time or the time required for the sample to completely detach.

Instrument structure: mainly composed of timing mechanism, test plate, loading plate, weight, frame, and standard pressure roller.