As temperaturescontinue to rise and extreme heatwaves become more frequent in the summer,along with the compounding of the urban heat island effect, the amount of heatabsorbed by building surfaces and windows increases significantly. This poses anew challenge for plastic window and door systems based on polyvinyl chloride(PVC), and requires a comprehensive review and reconsideration of the technicalstandards and specifications developed over decades in the PVC window system’sdevelopment process.
Currently, with the development of advancedcolored surface treatment technology, there has been a reduction in thetraditional technical limitations and application risks of colored plasticdoors and windows to a certain extent. For example, several famous Europeansuppliers of colored decorative films have successively developedlow-heat-absorption outdoor film products. This innovation ensures that theheat accumulated on the surface of the window and door frames is significantlyreduced. The use of special pigments can reduce the thermal effect ofnear-infrared radiation from the sun, preventing a considerable fraction ofthis radiation from penetrating into the interior of the frames and causingsurface reflection instead. The heat penetrating into the interior of theframes is significantly decreased, enabling the colored profile surfaces toremain cool, and keeping the window structure stable and durable.

Meanwhile, Renolit (https://www.renolit.com), a world-renowned high-end plastic film supplier from Germany, has overcome thefundamental problem of heat absorption on the surface of colored profiles byusing its innovative solar shielding technology (SST). SST, in combination withinfrared-reflective pigments, reduces heat accumulation and the temperaturedifference between the external and internal surfaces of frames. As a result,the long-standing profile deformation problem that has puzzled the industry isresolved. As demonstrated in the chart below, with this technology, severalhigh-end Renolit series for exterior decoration film users around the worldhave been given longer warranty periods. This provides a boon for the high-endconstruction industry, which is demanding in both external colors and windowand door durability.

Aside from theinnovation-driven research and development by famous foreign companies, someemerging domestic window film suppliers have also attempted to incorporateinfrared-reflective technology into their film-making processes. According toreports, several Chinese firms, including the Suzhou-based Lorika Corporation(LORIKA brand), have developed and launched single-color film products based oninfrared reflection technology. Based on its internal comparative tests, thisproduct can compete with similar overseas products in terms of temperature controltechnology indicators. The product's performance in comparison to conventionalcolored film products in temperature tests is also consistent with themacroscopic view in a video by Wintech.
In practicalapplications, colored PVC windows and doors based on infrared reflectiontechnology, such as those in Beijing, can reduce the surface temperature of thecolored profile by 6-8 degrees or even more in the summer.

Thermal Rise Comparison of Lorica ASA Anti-infrared Film and Competitor's Film

Color chart
In May 2022,Lorika's ASA exterior decoration film was selected by the CHINAPLAS organizersas "Asia Innovative New Product".

“ASIA INNOVATIVE NEW PRODUCT”
Lorika is thedomestic market leader in the field of ASA/PMMA high-performance films and areliable quality supplier in the fields of building film-coated steel plates,high-end automotive interior films, and automotive power battery insulationfilm sheets.