Manufacturing process of glass substrate
Glass substrate It plays a vital role in modern electronic equipment, especially in the production of displays, solar cells and electronic components. As the core foundation of load circuit and display material, it requires high transparency, accurate size and excellent surface quality. This article will discuss the manufacturing process of glass substrate in detail to help people better understand the key steps in its production.
1. Preparation of raw materials for glass substrate
The production of glass substrate starts from the selection and preparation of raw materials. The most commonly used glass substrate materials are Silicate glass Its main components include silicon dioxide 、 sodium 、 calcium 、 aluminum Etc. Raw materials usually exist in the form of powder or particles, which need to be melted at high temperature before entering the production process.
Smelting furnace It is the first key equipment for manufacturing glass substrate. Here, the raw material is heated to a high temperature of 1500 ° C to 1700 ° C, chemical reaction takes place and is converted into liquid glass. In this process, the temperature and heating speed in the furnace need to be strictly controlled to ensure the uniform quality of the melted glass.
2. Glass forming
After melting the liquid glass, the next step is the molding process. The shape of glass substrate mainly consists of Float method (Float Glass Process) or Calendering method (Roller Process).
- Float method : Float method is the most common glass substrate forming technology at present. It pours molten glass into molten metal pool (usually tin pool). As the glass floats in the metal pool, the liquid glass forms a flat thin layer, which can produce large glass substrates. This process is mainly used to produce large size display panels such as TV screens and smart phone screens.
- Calendering method : Calendering principle: The glass is made into thin sheets by hydraulic pressure between two rollers. This method is applicable to the production of small and thin glass substrates, especially in some high-precision electronic products.
No matter which molding method is used, the thickness and uniformity of glass are key control parameters in the manufacturing process.
3. Annealing and cooling
The formed glass substrate is still at high temperature and must be annealing Process to eliminate the internal stress in the glass. Annealing is a slow cooling process. The glass substrate will be gradually cooled to room temperature. This process is usually carried out in a specific temperature controlled furnace.
After annealing, the surface of the glass substrate will become smoother, the internal stress will be released, and the dimensional stability and impact resistance will be improved. In addition, annealing can also improve the optical properties of glass, especially its transparency and surface quality.
4. Cutting and finishing
After annealing, the cooled glass substrate enters Cutting and finishing Phase. At this stage, the glass substrate is cut to the required size according to the design requirements. Cutting is usually done by mechanical cutter or laser cutting. The mechanical cutter can accurately draw the cutting line along the glass surface, while the laser cutting can achieve a more refined cutting effect, especially in the production of small size and high-precision substrates.
There may be some burrs on the cut glass edge, which need to be Trimming handle. This process is usually completed by edging or polishing to ensure smooth edges of the substrate and avoid damage in subsequent use.
5. Surface treatment
The surface quality of glass substrate is very important for its subsequent use, especially in display screens and electronic components. The optical properties of the surface directly affect its performance. In this step, the glass substrate usually passes through coating 、 Coating or polishing Etc.
- coating : Common coatings include anti reflective coatings, hydrophobic coatings, etc. These coatings can improve the optical properties of glass substrates and improve their stain resistance.
- Coating : Plating thin films (such as ITO film) on the glass surface is an important step for making touch screens and electronic displays. The coating layer can improve the conductivity or other specific properties of the glass.
- polishing : In order to ensure the smoothness of glass substrate and reduce surface defects, polishing is an indispensable step. This process can eliminate tiny scratches and unevenness, and make the surface of the substrate clearer and brighter.
6. Inspection and packaging
Finally, the glass substrate after a series of processing will undergo strict quality inspection. Common inspection contents include:
- Dimension inspection : Ensure that the size of the glass substrate meets the design requirements.
- Optical inspection : Detect the transparency, surface defects, refractive index and other optical properties of the glass substrate.
- Mechanical strength test : Check the compression resistance, bending resistance and impact resistance of the base plate.
The glass substrates passing the inspection will be packaged and ready for the next link or delivery to the customer.