In aerospace engineering, each gram of weight corresponds to tens of thousands of dollars in launch costs. Multi layer insulation components (MLI) are the core means of passive thermal control for spacecraft - maintaining the operating temperature of internal equipment in the extreme temperature difference environment of space through the alternating stacking of dozens of aluminum plated films. The thickness of the reflective layer substrate in traditional MLI is usually between 12.5 μ m and 25 μ m. When engineers compress the substrate thickness from 25 μ m to 5 μ m, the amount of polymer material used decreases by about 80% for the same area. For a satellite containing MLI of tens of square meters, this weight reduction directly translates into an increase in payload or a decrease in launch costs.

But the question arises: can a 5 μ m PI substrate withstand the high and low temperature alternation, vacuum ultraviolet, and particle irradiation in space while reducing weight? More importantly, is it possible to achieve stable mass production?

2、 PI Al's material synergy: 'bidirectional rush' in extreme environments

The performance advantage of 5 μ m PI aluminum plated film comes from the deep synergy between PI substrate and aluminum coating at the material level.

3、 Vacuum evaporation: "growing" optical grade aluminum layer on 5 μ m substrate

The aluminum layer preparation of 5 μ m PI aluminum coating film adopts vacuum evaporation process - in a high vacuum environment, high-purity aluminum wire is heated and evaporated, and aluminum atoms are uniformly deposited on the surface of the PI film at a very high speed, forming a dense and bright aluminum layer. This process requires precise control of vacuum degree, evaporation temperature, evaporation rate, and substrate operating speed. Any deviation in any parameter may lead to oxidation, porosity, or insufficient adhesion of the aluminum layer.

Performing vapor deposition on ultra-thin substrates with a thickness of 5 μ m faces a series of challenges that are far more stringent than conventional thickness substrates:

4、 Key performance: Technical boundary of 5 μ m specification

5、 Application Layout: From Spacecraft to Flexible Electronics

6、 Selection considerations: from thickness to application scenarios

• Substrate thickness and weight reduction benefits:5 μ m is one of the ultra-thin specifications that can be mass-produced in the PI aluminum plated film product line. Compared to 12.5 μ m or 25 μ m substrates, 5 μ m has the most significant advantages in spacecraft MLI and flexible electronic weight reduction scenarios. The substrate thickness range of Advanced Institute Technology's PI aluminum plated film covers 5 μ m to 125 μ m, and can be flexibly selected according to specific application needs.
• Single sided and double-sided aluminum plating:Single sided aluminum plating maintains insulation on one side of the film while increasing conductivity and reflectivity on the other side; Double sided aluminum plating provides double-sided conductivity and reflection functions, and the MLI reflection efficiency designed with double-sided aluminum plating is higher, with a reflectivity of over 98%.
• Aluminum layer thickness:The thickness of the aluminum layer is usually in the range of 20 to 100 nanometers. The thicker the aluminum layer, the stronger the reflectivity and barrier properties, but the flexibility decreases. MLI applications typically choose an aluminum layer thickness of 50 to 100nm. Advanced Institute Technology achieves nanoscale control of aluminum layer thickness through precise regulation of vacuum evaporation parameters.
• Work environment:It is necessary to clarify the temperature range, irradiation conditions, and chemical environment of the application scenario. 5 μ m PI aluminum plated film works stably in a wide temperature range of -269 ° C to 400 ° C, suitable for the vast majority of extreme environments.
• Width and Customization:Advanced Institute Technology can provide customized solutions based on customers' requirements for substrate thickness, aluminum layer thickness, width, and roll length. PI aluminum plated film can be divided into two types: single-sided aluminum plating and double-sided aluminum plating, and the thickness of the aluminum layer can be customized according to needs.

7、 Conclusion

The essence of 5 μ m PI aluminum plated film is an engineering product that combines the extreme thinning of PI film with optical grade aluminum plating process. It is not simply "thinning" - at the 5 μ m scale, the thermal management, tension control, vacuum evaporation parameters, and coating uniformity of the material face engineering boundaries far more stringent than those of conventional thickness substrates. It is precisely these boundary conditions that have been overcome one by one - through precise process control, surface activation treatment, and high-temperature adhesion verification - that enable the 5 μ m PI aluminum coating to move from the laboratory to mass production, becoming the core material for high-end applications such as spacecraft thermal control, flexible electromagnetic shielding, and precision optics.

For engineers, understanding the process constraints and performance opportunities behind the thickness of 5 μ m - the extreme temperature resistance of PI, the optical reflection characteristics of aluminum, and the performance trade-offs of different aluminum layer thicknesses - is more valuable than simply remembering a specification.