High-temperature release films are widely used in the electronics, new energy, optics, and semiconductor industries, with PET (polyester) and PI (polyimide) being the two most common base materials. These materials each have their advantages in terms of temperature resistance, peel strength, mechanical strength, chemical stability, and cost. However, how to choose the right material to optimize production efficiency and ensure product quality?

Comparison of temperature resistance performance - PI is able to resistant higher temperatures, PET is suitable for medium temperature application.

The temperature resistance of high-temperature release film is one of the most critical indicators when selecting materials. PET and PI have significant differences in heat resistance and are suitable for different production needs.

1. The temperature resistance range of PET (polyester) substrate is generally between 100-200 ° C, and can withstand 230 ° C in a short period of time. However, prolonged exposure to environments above 200 ° C can cause deformation, brittleness, degradation, and other problems with PET.

Suitable for medium and low temperature processing techniques, such as FPC (flexible circuit board), optical film, lithium battery manufacturing, etc.

2. The temperature resistance range of PI (polyimide) material is 250-400 ° C, and it can maintain physical stability and mechanical strength in extreme high temperature environments without deformation or degradation.

Suitable for high-temperature processes such as semiconductor packaging, IC packaging and testing, LED packaging, aviation electronics, etc.

Comparison of Peel Performance.

PET is stable, the peel force of PI is more uniform.

The peeling force determines the effectiveness and process stability of the release film, and the stability of the peeling force depends on the compatibility between the substrate and the release coating.

1. The peeling performance of PET, with a smooth surface and good adhesion of the peeling layer. The peeling force range can be adjusted between 1-20g/25mm, making it suitable for light and medium release peeling applications. However, PET exhibits significant fluctuations in peel strength in high-temperature environments, which affects processing stability.

2. The peeling performance of PI is generally low due to its low surface energy, making it suitable for applications that require precise peeling at high temperatures. PI can still maintain uniform peeling force above 300 ° C and will not experience sudden changes in peeling force due to high temperature.

Mechanical strength and chemical resistance

During the production process, release films may need to withstand bending, stretching, mechanical impact, or chemical solvent corrosion. PET and PI exhibit different mechanical strength and chemical resistance.

1. PET has high mechanical strength and tensile strength, making it suitable for applications that require a certain degree of mechanical rigidity, such as FPC processing and optical film peeling. But PET is brittle and prone to fracture or deformation under high temperature or long-term use.

2. The mechanical strength of PI, as well as the tear resistance, bending resistance, and fatigue resistance of PI material, far exceed PET, making it suitable for applications that require repeated bending, such as semiconductor packaging and high-temperature lamination. PI also has excellent solvent resistance, acid and alkali resistance, and corrosion resistance, making it suitable for chemical processing environments.

Conclusion: PI has higher mechanical strength, stronger resistance to bending and chemical corrosion, and is suitable for harsh production environments, while PET is more suitable for ordinary processing techniques.