In the field of consumer electronics, the core pursuit of FPC design is "thinness" - the thinner the substrate, the smaller the bending radius, and the more it can fit into the narrow body space. But in the fields of power batteries, industrial control, and automotive electronics, there has been a fundamental shift in design constraints: engineers are no longer concerned about "whether they can be thinner by 0.5 μ m", but "whether they can withstand 100000 bends without breaking", "whether they can carry 3A current without significant temperature rise", and "whether they can maintain dimensional stability in temperature cycles from -40 ° C to 125 ° C.

What these scenarios require is not thinner substrates, but stronger 'skeletons'. The 75 μ m PI substrate demonstrates irreplaceable value in this engineering requirement.

2、 75 μ m PI substrate: Engineering logic for thick substrates

In the thickness spectrum of FPC substrates, 75 μ m (approximately 3mil) falls within the "thick substrate" range. Industry data clearly states that for FPC customers considering resistance to bending and compression, it is recommended that PI choose a thickness of 50 μ m or 38 μ m; And 75 μ m further enhances the mechanical strength and dimensional stability.

The core engineering value of 75 μ m PI substrate is reflected in three dimensions:

3、 75 25PI Copper Plating Film: High Reliability Combination of Thick Base Material and Thick Copper Layer

75 25PI copper plated film is a combination product of 75 μ m PI substrate and 25 μ m copper layer. This specification represents the high reliability direction of "thick substrate and thick copper layer" in the PI copper plating film product line.

The thickness of the copper layer is a key parameter that determines conductivity and current carrying capacity. Advanced Institute Technology's copper layer thickness covers 0.1-8 μ m, supporting customization for ultra-thin and thickened requirements. A copper layer thickness of 25 μ m belongs to the category of thick copper layers, which means lower square resistance and higher current carrying capacity, suitable for power lines and power FPC applications that require carrying larger currents.

4、 75 10PET Copper Plating Film: Cost Optimization Scheme for Thick Substrate PET

Compared with PI, PET (polyethylene terephthalate) substrate has significant cost advantages, but it is inferior to PI in terms of heat resistance, dimensional stability, and mechanical properties. The 75 10 PET copper plated film uses a combination of 75 μ m PET substrate and 10 μ m copper layer, which is consistent with the engineering positioning of 75 25 PI in "thick substrate", but the substrate type is different.

The 75 μ m thick PET substrate provides good mechanical strength and dimensional stability, while the 10 μ m copper layer provides lower resistance and higher current carrying capacity. This specification is suitable for applications that have certain cost requirements, moderate working temperature (PET long-term use temperature usually does not exceed 120 ° C), but require certain mechanical strength and conductivity. In the PET copper plated film product line, this thickness specification is in the medium thickness range, balancing mechanical performance and cost control.

5、 25 0.5PET Copper Plating Film: Lightweight Selection of Thin Copper Layer on Thin Substrate

The 25 μ m PET copper plated film is composed of a 25 μ m PET substrate and a 0.5 μ m copper layer. This specification stands in stark contrast to the 75 μ m thick substrate - it caters to engineering needs that are completely different from thick substrates: lightweight, high-precision, and cost sensitive.

25 μ m is a commonly used thickness for PET film, while a thin copper layer of 0.5 μ m is suitable for high-precision thin circuit fabrication. Advanced Institute Technology uses copper with a purity of 99.999% as the target material, and deposits a metal copper film on the surface of PET through vacuum nano coating technology. This specification is suitable for scenarios that require high levels of slimness and line accuracy, but low requirements for current carrying capacity. Thin copper layers can obtain finer lines after etching, suitable for applications such as high-density interconnect (HDI) FPC and sensor electrodes.

6、 Product series comparison and selection logic

Engineers should weigh the following dimensions when selecting:

7、 Key Performance: Advanced Institute Technology's Technical Confidence

According to the official website of the Advanced Institute of Technology, the key performance indicators of this series of products are as follows:

8、 Application scenarios: From power batteries to wearable devices

9、 Conclusion

The essence of 75 μ m PI copper plated film and PET copper plated film is to provide engineering choices with different positioning between the "performance" and "cost" of FPC. 75 25PI, with the high temperature resistance of PI substrate and the high conductivity of thick copper layer, is designed for harsh applications with high reliability and high current; 75 10PET and 25 0.5PET are aimed at consumer electronics and cost sensitive scenarios due to the cost advantage and flexible thickness of PET substrates.

For FPC design engineers, understanding how substrate type (PI vs PET) and substrate thickness (75 μ m vs 25 μ m) jointly determine the temperature resistance, mechanical strength, and cost of FPC is more valuable than simply comparing one parameter. Advanced Institute Technology provides complete customization capabilities for PI copper plated films ranging from 5 μ m to 125 μ m and PET copper plated films ranging from 4.5 μ m to 188 μ m, providing flexible material selection space for different application scenarios.