Aluminum-plastic co-extruded profiles can effectively block ultraviolet rays to a certain extent for the following reasons:

- Plastic outer layer of the blocking effect: aluminum-plastic co-extruded profile of the outer layer of plastic, usually using polyvinyl chloride (PVC) and other materials. pvc itself has a certain degree of ultraviolet absorption ability, can absorb part of the ultraviolet ray, reduce ultraviolet rays through the profile into the room. At the same time, in the production process, manufacturers will also add ultraviolet absorbers and other additives to further enhance the outer layer of plastic on the absorption of ultraviolet rays and the ability to block. These additives are able to convert the absorbed UV energy into heat or other harmless forms of energy, thus avoiding UV damage to the internal structure of the profile and the contents of the room.

- Reflection of the aluminum alloy layer: The aluminum alloy layer inside the aluminum-plastic co-extruded profile has good reflection properties. When UV rays irradiate the surface of the profile, the aluminum alloy layer can reflect part of the UV rays so that they cannot penetrate the profile. Aluminum alloy has high reflectivity, especially for the shorter wavelength ultraviolet rays, it can effectively reflect them back and reduce the amount of ultraviolet transmission.

- Synergy of the overall structure: The multi-cavity structure and tight composite structure of aluminum co-extruded profiles also help to block UV rays. The multi-cavity structure increases the number of reflections and scatterings of UV rays inside the profile, so that UV rays are continuously weakened in the process of propagation. The tight composite structure can avoid the direct penetration of ultraviolet rays due to gaps or holes, which ensures the overall UV-blocking performance of the profile.

Although aluminum-plastic co-extruded profiles have a certain degree of UV-blocking ability, but can not completely prevent the transmission of ultraviolet rays. If the ultraviolet protection requirements are higher, you can choose a better ultraviolet-blocking performance of the coated glass or Low - E glass on the door and window glass, and aluminum co-extruded profiles used in conjunction to further improve the ultraviolet protection effect of the entire door and window system.