The hardness test of the glass cover of a touch screen is an important means of evaluating its surface durability and scratch resistance. As the interface between user and device interaction, the touch screen is often subject to external forces such as finger touch and hard object scratching, etc. Insufficient hardness will easily lead to surface scratches or damage, affecting the display effect and service life. Therefore, the hardness test can ensure that the touch screen can maintain good appearance and performance under various usage scenarios.
1. Glass cover hardness test steps
(1) Material selection and pretreatment
Confirm the glass type (e.g. soda-lime glass, aluminum-silicate glass, chemically strengthened glass, etc.), and clean and de-static treatment to avoid test interference.
(2) Hardness test method
Mohs hardness test: Scratch the surface with a standard mineral scratching tool (10 grades from talc to diamond) at a fixed pressure, observe the lowest grade at which scratches appear, and judge the glass's ability to resist scratches.
Pencil Hardness Test (JIS K5600 standard): A pencil of different hardness (e.g. 9H to 6B) is scratched at an angle of 45° to detect the highest hardness level with no visible scratches.
Indentation hardness test (e.g. Vickers hardness): Pressure is applied through a diamond indenter, the diagonal length of the indentation is measured, and the hardness value is calculated (suitable for quantifying compressive properties).
(3) Impact resistance test
Falling ball test: A steel ball is dropped freely from different heights to impact the center of the glass to detect the critical height of rupture (e.g. 1m height to withstand the impact of a 227g steel ball).
Impact head test: simulate the impact of sharp objects (e.g. IK grade test) to evaluate the shatter resistance.
2. The core benefits of glass cover hardness testing for touchscreens to consumers:
(1) Durability guarantee
High hardness (e.g. Mohs 6 or above) can resist daily scratches such as keys and grit, prolonging the life of the screen and reducing replacement costs.
(2) Impact security
Tested glass reduces the risk of falling and shattering, protects internal display modules (e.g. smartphones, in-vehicle touchscreens), and avoids maintenance costs and safety hazards.
(3) Optimization of user experience
Hardness and surface smoothness are related to ensure smooth and unobstructed touch control; coating test results directly affect the actual experience of anti-fingerprint, anti-reflective and so on.
(4) Long-term cost savings
Durable glass cover reduces the reliance on film and protective case, and lowers the expenditure on accessories (e.g. some consumers give up filming due to the high hardness glass).
(5) Application Scene Adaptation
Industrial or outdoor equipment screens pass harsh tests (e.g., high-temperature impact), and consumers can choose products that match the hardness according to their needs.
Through scientific hardness testing, consumers can more accurately choose the touch screen products that meet their needs, balancing cost and performance, and ultimately enhance the use of satisfaction and cost-effective products.