SUCCESSIVELY PEELABLE COEXTRUDED POLYMER FILM WITH EXTENDED UV STABILITY

摘要

Multilayered polymer films are configured so that successive constituent layer packets can be delaminated in continuous sheet form from the remaining film. The films are compatible with known coextrusion manufacturing techniques, and can be made without adhesive layers between layer packets that are tailored to be individually peelable from the film. Instead, combinations of polymer compositions are used to allow non-adhesive polymer layers to be combined such that irreversible delamination of the film is likely to occur at interfaces between layer packet pairs. Some polymer layers, including at least one embedded layer, may include an ultraviolet (UV) light stabilizer such as a UV absorber, antioxidant, or hindered amine light stabilizer (HALS), and these layers may be positioned at the front of each layer packet. After the UV-stabilized layer of one packet has been used, the packet can be peeled away to expose a new UV-stabilized layer of the next layer packet.

主权项

1. A film comprising a stack of polymer layers, the polymer layers being organized into layer packets, each of the layer packets having at least two of the polymer layers;
wherein attachment between adjacent layer packets is weak enough to permit the layer packets to be separately irreversibly delaminated from a remainder of the stack, and the stack is configured to promote such irreversible delamination between such layer packets; wherein all of the polymer layers in the stack of polymer layers have respective polymer compositions that are coextrudable with each other; and wherein at least one of the polymer layers in a plurality of the layer packets comprises one or more ultraviolet (UV) light stabilizer.