Corning (America), Schott (Germany) and AGC (Japan) are three leading companies in the optical glass field. When thinking about the difference among different glass materials, better glass comes with greater light transmittance.
The thinner the screen protector, the better the hand sensation. Now if you need to buy screen protector, it is best to buy 0.3mm. Relatively speaking, this is the most cost-effective thickness.
But the thinner, the better. So far, only two types of glass without being treated could be 0.2mm thin in the market, including Corning and Schott. There is also a 0.2mm tempered glass material, which is thinned by soaking a 0.33mm thick glass material in a chemical solution. After treatment, thickness of this thinned glass material will not be evenly distributed. This is why Corning and Schott glass could be expensive as raw materials.
Through the first cutting process, the glass gets processed to rectangular small-size. And then we need to cut the glass material into the size suitable for the mobile phone screen.
Next step is the arc edge polishing. It polishes the straight edge tempered film to a 2.5D arc edge one, which presents more visual enjoyment but could be costlier.
And then it is necessary to put the glass into the ultrasonic wave and add the cleaning agent to clean it. This removes scratches, water residues, fingerprints, dust and etc.
Next step is tempering the glass. The semi-finished glass film reacts with potassium nitrate in a high-temperature furnace to increase the strength and toughness of the glass film.
After the glass is tempered, the strength increases, and its compressive strength can reach 125MPa or more, which is 4 to 5 times stronger than ordinary glass.
Next is vacuum coating, which is to put the glass in an electroplating furnace and put anti-fingerprint pills. The pills will become mist and adhere to the glass evenly in a high-temperature vacuum environment. The cost of the imported vacuum coating machine is over one million. This could reduce the fingerprint residue on the screen protector.
Last step is to put the adhesives to the screen protector. The side where the screen protector is in contact with the phone needs to be coated with a layer of epoxy resin AB glue so that it can be attached. Right now in the market, AB glue products with high quality are mostly imported from Japan and South Korea. Others lead to problems such as poor light transmittance, easy to produce bubbles, edge warping, and etc. Our supplier is from Korea.
These complete the production process of a screen protector.
Tests To Do
Drop Ball Test
The 0.8kg steel ball falls from 3.94 feets high, the glass can be kept intact. The strength and elasticity of tempered glass is much greater than that of ordinary glass. A piece of tempered glass of 1200mm×350mm×6mm can have a bending deflection of up to 100mm after being stressed. When the external force is removed, it can still return to its original shape. The bending deformation of the glass can only be a few millimeters.
A good tempered film will not splash around and hurt people when broken. Three processes are most likely to produce defective screen protector if not done well. Bad cutting and polishing processes can cause glass edges to burst. The tempering time in the furnace is not enough, and the poor use of potassium nitrate will also cause the strength and toughness to decrease.
Water Drop Contact Angle Test
How to check the coating effect? There are generally three ways to identify.
1) Swipe with your fingers over the screen, the smoother, the better.
2) The smaller the empty angle formed by the contact between the water drop and the glass surface, the better.
Why Benks Corning® Screen Protector Is Expensive?
Some customers question why Benks screen protectors are expensive to buy. You could trace clues through reading the contents by far. Benks insists on using the premium materials, strengthening the production process by adopting imported materials and machines, and running a lot of meticulous tests on the final product before shipping to the customers. We are proud of what we have been doing and we will continue to provide our customers high quality products and satisfactory services.