Mobile phone tempered film test

Oleophobic layer test

The first thing to do is the oleophobic layer test: In order to ensure the user’s daily use experience, most of the mobile phone tempered films now have an oleophobic coating. This type of AF anti-fingerprint coating has extremely low surface tension, and ordinary water droplets, Oil droplets can maintain a large contact angle when they touch the surface of the material, and aggregate into water droplets by themselves, which is easy for users to clean.
 
Although the principles are similar, the spraying process of the oleophobic layer is also different. At present, the mainstream processes on the market are plasma spraying and vacuum plating coating. The former uses plasma arc to clean the glass first, and then sprays the oleophobic layer. The combination is closer, which is the mainstream treatment process on the market at present; the latter sprays anti-fingerprint oil onto the glass in a vacuum environment, which is stronger overall and has the highest wear resistance.

In order to simulate daily use, we adopted the most universal dripping method, using a dropper to extrude water droplets from a high place onto the tempered film to see if the surface tension can allow the water droplets to aggregate into a spherical shape. The water drop angle ≥ 115° is optimal.
 
All mobile phone tempered films have a hydrophobic and oleophobic layer. The process used is mentioned in the description page of some products. The high-end explosion-proof tempered film adopts “upgraded electroplating coating”, “vacuum electroplating anti-fingerprint AF process”, etc.
 
Some users may be curious, what is anti-fingerprint oil? Its raw material is AF nano-coating, which can be evenly sprayed on the substrate such as tempered film by spraying, electroplating, etc., to achieve dustproof, waterproof, oil-proof, anti-fouling, anti-fingerprint, smooth and abrasion-resistant effects. If you really hate fingerprints all over the screen, you can choose whether the earpiece is dustproof & the body is curved
 
I believe old iPhone users must have the impression that after using their iPhone for a long time, the microphone above the fuselage will always accumulate a lot of dust and stains, which not only affects the sound playback, but also the overall look and feel is very poor.

For this reason, some tempered films specially designed for the iPhone series have added “earpiece dust-proof holes”, which can not only isolate dust while ensuring normal volume playback, but also play a waterproof role. It can be seen that half of the tempered film of mobile phones has been treated with dustproof earpieces. However, the openings between the membranes are also different. The number of dust-proof holes in Turas and Bonkers is relatively large, and the relative dust-proof effect and waterproof effect are better;

In terms of arc edge treatment, the processes adopted by different tempered films also have their own advantages and disadvantages. There are obvious differences in touch according to different materials. Most of the tempered films use 2.5D edge technology, which is chamfered by a sweeping machine. After polishing, the edge of the membrane body has a certain curvature, which feels excellent.

Next we enter the highlight of this test: extreme physical tests, including three types of drop test, pressure test, and hardness test, all of which will have a “destructive blow” to the mobile phone film
 
Hardness Testing
If you want to ask mobile phone users why they need to replace the mobile phone film, the answer of “too many scratches” will definitely not be less. Who usually does not carry keys, cigarette cases or the like in their pockets when they go out, once there are scratches on the overall appearance of the mobile phone screen dramatically drop.
 
In order to simulate daily scratches, we use Mohs stones of different hardness for testing
In the test, all tempered films can withstand scratches with a hardness above 6H, but if the hardness is increased, scratches will be left immediately, and even cracks will appear on the whole. It can keep the hand feeling smooth for a long time. The wear resistance can reach 10000 times.
 
drop ball test
Some friends may ask, what is the significance of this ball drop test? In fact, the main test of this item is the impact resistance of the tempered film. The higher the height of the ball, the stronger the impact force. The current tempered film is mainly made of lithium-aluminum/high-aluminum materials, and has undergone secondary treatment, which is basically very tough.
In order to simulate daily use, we set the limit height of this test to 180cm, simulating the height of a person, and after exceeding the value of 180cm, we will directly give it a full score. But after being cruelly “destroyed” by the small ball, they all withstood the impact of the iron ball without any damage.
Stress Strength Test
In daily life, the tempered film of a mobile phone needs to withstand not only the instantaneous impact, but also the overall strength. The author once broke several mobile phone films, and the scene at that time was really “horrible”.
For this test, we purchased a push-pull force gauge to perform detailed tests on the pressure that different areas on the screen can bear.