Iridescent film with thermoplastic elastomeric components

Abstract

Improvements in multilayer light reflecting film are effected by the use of a thermoplastic elastomer resin in a system in which two or more resinous materials form a plurality of the layers.

What is claimed is: 
     
       1. A transparent thermoplastic resinous laminate film of at least 10 very thin layers of substantially uniform thickness .Iadd.in the range of about 30-500 nm.Iaddend., said layers being generally parallel, the contiguous adjacent layers being of different transparent thermoplastic resinous materials of which one is a thermoplastic elastomer .Iadd.and the other is not a thermoplastic elastomer.Iaddend., the contiguous adjacent layers differing in refractive index by at least about 0.03.Iadd., the thermoplastic elastomer being a segmented thermoplastic copolyester elastomer of a thermoplastic hard segment and a soft elastomeric segment.Iaddend.. 
     
     
       2. The transparent thermoplastic laminate film of claim 1 wherein the outermost layers of the film are each at least 5% of the total thickness of the film. 
     
     
       3. The transparent thermoplastic resinous laminate film of claim 1 having at least 35 layers. 
     
     
       4. The transparent thermoplastic resinous laminate film of claim 3 having at least about 70 layers. 
     
     
       5. The transparent thermoplastic resinous laminate film of claim 4 wherein said adjacent resinous material has a refractive index which is lower by at least about 0.06. 
     
     
       6. The transparent thermoplastic resinous film of claim 1 wherein at least one layer is polybutylene terephthalate. 
     
     
       7. The transparent thermoplastic resinous laminate film of claim 6 wherein the thermoplastic elastomer is a segmented block copolymer of polybutylene terephthalate and .[.polyester.]. .Iadd.polyether .Iaddend.glycol. 
     
     
       8. The transparent thermoplastic resinous laminate film of claim 6 wherein the thermoplastic elastomer is a segmented block copolymer of polybutylene terephthalate and polyether imide. 
     
     
       9. The transparent thermoplastic resinous laminate film of claim 6 having at least 70 substantially uniformly thick layers. 
     
     
       10. The transparent thermoplastic resinous laminate film of claim 1 wherein at least one layer is polyethylene terephthalate. 
     
     
       11. The transparent thermoplastic resinous laminate film of claim 10 wherein the thermoplastic elastomer is a segmented block copolymer of polyethylene terephthalate and polyether glycol. 
     
     
       12. The transparent thermoplastic resinous laminate film of claim 10 wherein the outermost layer resin is a glycol modified polyethylene terephthalate made from ethylene glycol and cyclohexanedimethanol. 
     
     
       13. The transparent thermoplastic resinous laminate film of claim 10 having at least 70 substantially uniformly thick layers. 
     
     
       14. A transparent thermoplastic resinous laminate film of at least 10 very thin layers of substantially uniform thickness .Iadd.in the range of about 30-500 nm.Iaddend., said layers being generally parallel, the contiguous adjacent layers being of different transparent thermoplastic resinous materials, the contiguous adjacent layers differing in refractive index by at least about 0.03 wherein each of the different transparent thermoplastic resinous materials is a segmented block copolymer of a terephthalate polymer and a .[.polyester.]. .Iadd.polyether .Iaddend.glycol or polyether imide. 
     
     
       15. The transparent thermoplastic resinous laminate film of claim 14 wherein both thermoplastic elastomers are segmented block copolymers of polybutylene terephthalate and polyether glycol. 
     
     
       16. The transparent thermoplastic resinous laminate film of claim 14 having at least 70 substantially uniformly thick layers.