Chemical resistance test for touch panels is an important part of evaluating their durability and reliability, especially in application scenarios where they may be exposed to chemicals (e.g., industrial equipment, medical equipment, or outdoor environments). The following is a detailed description of chemical resistance test for touch panels:
1. Test Purpose
Evaluate chemical resistance: To test the corrosion resistance of touch panels when exposed to chemicals (e.g. acids, alkalis, solvents, grease, etc.).
Ensure long-term reliability: to ensure that the touch panel can still work properly in complex environments (e.g. high temperature and humidity, chemical pollution).
Comply with industry standards: Meet the requirements of chemical resistance in related industries (e.g. automotive, medical, consumer electronics).
2. Test Methods
(1) Chemical immersion test
Method: Completely immerse the touch panel sample in a specific chemical solution (e.g. acid, alkali, brine, organic solvent, etc.) and observe the surface changes under certain temperature and time conditions.
Criteria: Temperature: room temperature or high temperature (e.g. 40℃, 60℃).
Time: 24 hours, 48 hours, 72 hours or longer.
Solution: choose according to the application scenario
E.g.: Acidic solution: 3% hydrochloric acid (HCl).
Alkaline solution: 5% sodium hydroxide (NaOH).
Saline solution: 5% sodium chloride (NaCl).
Organic solvents: isopropyl alcohol, acetone, etc.
Evaluation index: Surface appearance (e.g. discoloration, corrosion, blistering, cracking).
Electrical performance (e.g. resistance, capacitance change).
Function test (e.g. touch sensitivity, multi-touch).
(2) Chemical wipe test
Method: Repeatedly wipe the surface of the touch panel with a cotton cloth or sponge soaked with chemical solution to simulate chemical substance contact in actual use.
Standard: Number of wiping times: 100, 500 or 1000 times.
Pressure: Simulate the pressure of finger pressing (e.g. 500g).
Solution: Same as immersion test.
Evaluation indicators: Whether the surface coating is peeling off.
Whether the touch function fails.
Surface roughness change.
3. Evaluation of test results
Appearance inspection: Use microscope or high magnification camera to observe the surface for corrosion, discoloration, cracks or coating peeling.
Electrical performance test: Measure the resistance, capacitance, insulation resistance and other parameters of the touch panel to ensure that it meets the specifications.
Function test: Use the touch tester to check whether the touch sensitivity, linearity, and multi-touch function are normal.
4. Test Precautions
Sample preparation: Make sure the sample surface is clean and free of grease or fingerprints.
Use the original sample without special treatment for testing.
Environmental control: The test environment should be maintained at constant temperature and humidity to avoid external contamination.
Safety measures: Chemical solutions are corrosive, protective gloves and goggles should be worn during operation.
Proper disposal of chemical waste solution is required after testing.
5. Common application scenarios
(1) Industrial control: The touch panel may come into contact with oil, acid and alkali solutions.
(2) Medical equipment: need to tolerate disinfectants (e.g. alcohol, sodium hypochlorite).
(3)Automotive electronics: need to withstand high temperature and high humidity and salt spray environment.
(4) Outdoor equipment: need to withstand ultraviolet rays, acid rain and other natural environments.
Chemical resistance test for touch panels is key to ensuring their reliable operation in complex environments. Through standardized testing methods, chemical resistance can be assessed and provide a basis for material selection, surface treatment and structural design, thus enhancing product durability and market competitiveness.