Technical principle: Using reactive magnetron sputtering coating method, combined with computer materials and optical aided design, the film system is subjected to interface matching, surface protection and overall optical performance optimization to develop a high-quality solar heat absorbing film with spectral selectivity. In the solar light band, it has the highest absorption rate as possible and the lowest radiation rate as possible in the infrared thermal radiation band.

Main technical indicators: The absorption rate of the solar heat absorbing film at 300-2500nm is not less than 0.95 (AM1.5), the emissivity at 2500-48000nm is not more than 0.04, the attenuation coefficient of the optical properties of the surface of the heat absorber is not higher than 0.005, the heat absorber can withstand salt spray corrosion for 24 hours, and the coating aging property, coating adhesion and other properties meet the requirements of GB/T 26974-2011.

Technical advantages, application characteristics, economic and social benefits, etc.: The "high-quality solar heat absorption film" developed and designed by China General Academy of Building Materials Science has completely independent intellectual property rights. The core properties of the product's solar spectral absorption rate (higher than 96%), infrared heat radiation rate (lower than 4%) are better than similar products at home and abroad currently on the market; and it has good high temperature durability, salt spray resistance and aging resistance; The coating color can be flexibly adjusted according to customer needs. Currently, there are series of products in different colors such as gold, purple, blue, green, and coffee. In addition, the coating technology has the characteristics of simple and stable process, good controllability, green and pollution-free, and low target cost; the coating equipment has low investment and good equipment compatibility (simultaneously producing solar absorption films, low-emission coated glass, and solar control coated glass) and other characteristics, and can transform the existing coated glass production line.

Preliminary application demonstration situation:

At present, some solar heat absorption film products have been demonstrated and applied in the photothermal power generation collectors of Yikebo Energy Shanghai Technology Co., Ltd.

The industrial production and coating technology of high-quality solar heat absorption films has completed the process debugging under the production mode on the flat glass coating production line of China National Building Materials Neijiang Glass High-tech Co., Ltd., and is preparing for large-scale production and put into the market.

Status of R & D funding obtained: ■ National Science and Technology Support Plan

Application situation or application prospects: Solar heat absorbing film, commonly known as blue film, is the core material of solar thermal conversion collectors. It is suitable for solar thermal systems at different use temperatures and environments such as flat solar water heaters, seawater desalination, and solar thermal power generation. Among them, flat-plate collectors are increasing at an annual rate of 30%. At present, the country's production capacity totals about 13 million square meters, and the market exceeds demand.

Investment estimates:

1. Transformation of the existing coated glass production line: Depending on the specific production line configuration, generally within 1 million yuan.

2. Design and manufacture new production lines: Depending on the specific production capacity, the investment in a production line with a production capacity of 2.5 million square meters is 30 - 40 million yuan.