Multilayer polymer sheets

Patent metadata

Field	Value
Publication number	US-11213369-B2
Application number	US-202016835101-A
Country	US
Kind code	B2
Filing date	Mar 30, 2020
Priority date	May 14, 2012
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

Multilayer polymer sheets are provided, as well as related methods, systems, and appliances.

First claim

What is claimed is:

1. A multilayer sheet comprising:
a first outer polymer layer comprising co-polyester and a second outer polymer layer comprising co-polyester, each of the first and second outer polymer layers having a hardness of about 60 A to about 85 D, wherein each of the first outer polymer layer and the second polymer layer comprises a compression set greater than 40% after 24 hours at 70° C.; and
an inner polymer layer comprising thermoplastic polyurethane, wherein the multilayer sheet is incorporated into an orthodontic appliance.

2. The multilayer sheet of claim 1 , wherein at least one of the first outer polymer layer and the second outer polymer layer comprises one or more of: a flexural modulus of greater than about 35,000 psi, or a light transmission between 400 nm and 800 nm of greater than about 75%.

3. The multilayer sheet of claim 1 , wherein at least one of the first outer polymer layer and the second outer polymer layer comprises a blend of polymeric materials, including the co-polyester and one or more materials selected from the group consisting of: a thermoplastic polyurethane elastomer, a silicone rubber, an elastomeric alloy, a thermoplastic elastomer, a thermoplastic vulcanizate elastomer, a block copolymer elastomer, a polyolefin blend elastomer, a thermoplastic co-polyester elastomer, and a thermoplastic polyamide elastomer.

4. The multilayer sheet of claim 1 , wherein the inner polymer layer comprises a blend of polymeric materials, including the thermoplastic polyurethane and one or more materials selected from the group consisting of: a polyester, a co-polyester, a polypropylene, a polyethylene, a polypropylene and polyethylene copolymer, an acrylic, a polyetheretherketone, a polyamide, a polyethylene terephthalate, a polybutylene terephthalate, a polyetherimide, a cyclic block copolymer, a polyethersulfone, and a polytrimethylene terephthalate.

5. The multilayer sheet of claim 1 , wherein the inner polymer layer comprises at least two layers, and wherein one layer is the thermoplastic polyurethane and at least one layer of the inner polymer layer independently comprises a polymeric material selected from the group consisting of: a polyester, a co-polyester, a polypropylene, a polyethylene, a polypropylene and polyethylene copolymer, an acrylic, a polyetheretherketone, a polyamide, a polyethylene terephthalate, a polybutylene terephthalate, a polyetherimide, a cyclic block copolymer, a polyethersulfone, and a polytrimethylene terephthalate, and a combination thereof.

6. The multilayer sheet of claim 1 comprising a thickness of between 500 μm and 1200 μm.

7. The multilayer sheet of claim 1 , wherein the inner polymer layer comprises at least one of: an elongation at yield of greater than about 4%, an elongation at break of greater than about 70%, a stress relaxation of greater than about 10% at 24 hours testing at a relative humidity of between 90% and 100%, a light transmission between 400 nm and 800 nm of greater than about 75%, or a tensile strength at yield between 4000 psi and 6500 psi.

8. A multilayer sheet comprising:
a first outer polymer layer comprising co-polyester and a second outer polymer layer comprising co-polyester, each of the first and second outer polymer layers having a flexural modulus of greater than about 35,000 psi and a compression set of greater than 40% after 24 hours at 70° C.; and
an inner polymer layer comprising thermoplastic polyurethane, the inner polymer layer having an elongation at break of greater than about 70%, wherein the multilayer sheet is incorporated into an orthodontic appliance.

9. The multilayer sheet of claim 8 , wherein each of the first and second outer polymer layers each have a hardness of about 60 A to about 85 D.

10. The multilayer sheet of claim 8 , wherein at least one of the first outer polymer layer and the second outer polymer layer comprises a light transmission between 400 nm and 800 nm of greater than about 75%.

11. The multilayer sheet of claim 8 , wherein at least one of the first outer polymer layer and the second outer polymer layer comprises a blend of polymeric materials, including the co-polyester and one or more materials selected from the group consisting of: a thermoplastic polyurethane elastomer, a silicone rubber, an elastomeric alloy, a thermoplastic elastomer, a thermoplastic vulcanizate elastomer, a block copolymer elastomer, a polyolefin blend elastomer, a thermoplastic co-polyester elastomer, and a thermoplastic polyamide elastomer.

12. The multilayer sheet of claim 8 , wherein the inner polymer layer comprises a blend of polymeric materials, including the thermoplastic polyurethane and one or more materials selected from the group consisting of: a polyester, a co-polyester, a polypropylene, a polyethylene, a polypropylene and polyethylene copolymer, an acrylic, a polyetheretherketone, a polyamide, a polyethylene terephthalate, a polybutylene terephthalate, a polyetherimide, a cyclic block copolymer, a polyethersulfone, and a polytrimethylene terephthalate.

13. The multilayer sheet of claim 8 , wherein the inner polymer layer comprises at least two layers, and wherein one layer is the thermoplastic polyurethane and at least one layer of the inner polymer layer independently comprises a polymeric material selected from the group consisting of: a polyester, a co-polyester, a polypropylene, a polyethylene, a polypropylene and polyethylene copolymer, an acrylic, a polyetheretherketone, a polyamide, a polyethylene terephthalate, a polybutylene terephthalate, a polyetherimide, a cyclic block copolymer, a polyethersulfone, and a polytrimethylene terephthalate, and any combination thereof.

14. The multilayer sheet of claim 8 comprising a thickness of between 500 μm and 1200 μm.

15. The multilayer sheet of claim 8 , wherein the inner polymer layer comprises at least one of: an elongation at yield of greater than about 4%, a stress relaxation of greater than about 10% at 24 hours testing at a relative humidity of between 90% and 100%, a light transmission between 400 nm and 800 nm of greater than about 75%, or a tensile strength at yield between 4000 psi and 6500 psi.

Assignees

• Align Technology Inc

Inventors

• Li Chunhua
• Chen Yan
• Pudleiner Heinz
• Meyer Klaus
• Nickel Joerg
• Pehlert Craig

Classifications

• B32B7/022

  Mechanical properties · CPC title

• B32B2307/536

  Hardness · CPC title

• A61F5/56

  Devices for preventing snoring · CPC title

• B32B2307/54

  Yield strength; Tensile strength · CPC title

• B32B2250/40

  Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA · CPC title