Film arrangement
A transparent multi-layered film arrangement comprising at least three layers, wherein the film arrangement comprises one layer is made of a biodegradable polylactic acid (PLA) and a polyglycol as plasticizer, said polyglycol having a molecular weight of between 35,000 and 4,000,000, and at least two outer layers, each of said two outer layers being made of PLA.
1. A transparent multi-layered film arrangement comprising at least three layers, wherein the film arrangement comprises:
one layer made of a biodegradable polylactic acid (PLA) and a polyglycol as plasticizer, said polyglycol having a molecular weight of between 35,000 and 4,000,000, and said polyglycol consisting of units derived from ethylene glycol, propylene glycol, or a mixture thereof; and
at least two outer layers, each of said two outer layers being made of PLA.
2. A film arrangement according to claim 1 , wherein the plasticizer is a polyethylene glycol or a polypropylene glycol.
3. A film arrangement according to claim 1 , wherein the molecular weight of the polyglycol plasticizer is between 35,000 and 400 000.
4. A film arrangement according to claim 1 , wherein the PLA is admixed with 0.01 to 40 weight percent of plasticizer.
5. A film arrangement according to claim 1 , wherein the biodegradable PLA layer is accompanied by further layers which are likewise biodegradable.
6. A film arrangement according to claim 5 , wherein the film is provided with at least one barrier layer.
7. A film arrangement according to claim 1 , wherein the outer layers of PLA do not contain any plasticizer, while at least one inner layer of PLA does contain the plasticizer.
8. A film arrangement according to claim 1 , wherein the outer layers have a small plasticizer content between 0.1 and 10%, and an inner layer of PLA has a higher plasticizer content than the outer layers.
9. A film arrangement according to claim 1 , wherein at least one additive selected from the group consisting of dyes, optical brighteners, antiblocking agents, antistats, antifogging agents, slickers, UV absorbers, fillers, peeling additives, sealing additives, antioxidants processing auxiliaries and combinations thereof is present at least in an outer layer of the film arrangement.
10. A film arrangement according to claim 1 , wherein the film arrangement is oriented.
11. A film arrangement according to claim 1 , wherein at least an outer layer of the film arrangement bears a printed image.
12. A process for producing the film arrangement of claim 1 , wherein the biodegradable PLA is extruder mixed and homogenized with the plasticizer and the PLA layer containing said plasticizer is coextruded together with further layers.
13. Method for forming receptacles which comprises thermoforming the film arrangement of claim 1 to form a receptacle.
14. Method of claim 13 , wherein the film arrangement is sealed to further films or film arrangements.
15. Method of claim 13 wherein the film arrangement is used as backsheet film for sanitary articles.
16. Method according to claim 14 , wherein the film arrangement is used as backsheet film for sanitary articles.