Align Technology, Inc.

Covestro Deutschland Ag

Covestro Intellectual Property Gmbh & Co. Kg

Craig Pehlert

Chunhua Li

Yan Chen

Heinz Pudleiner

Klaus Meyer

Joerg Nickel

Wolfgang Bräuer

Juergen Winkler

Jürgen Winkler

Wolfgang Braeuer

Wolfgang Brauer

Jörg Nickel

The invention relates to a multi-layer, preferably co-extruded, plastic film with improved modulus properties, which is suitable, in particular, for producing three-dimensionally shaped articles.

Multi-layer film with improved modulus properties

A dental appliance for positioning a patient's teeth includes a removable orthodontic tooth positioning appliance having teeth receiving cavities shaped to directly receive at least some of the patient's teeth and apply a resilient positioning force to the patient's teeth. The appliance includes a hard polymer layer having a hard polymer layer elastic modulus disposed between a first soft polymer layer having a first soft polymer layer elastic modulus and a second soft polymer layer having a second soft polymer layer elastic modulus. The hard polymer layer elastic modulus is greater than each of the first soft polymer layer elastic modulus and the second soft polymer layer elastic modulus. At least one of the first soft polymer layer and the second soft polymer layer has a flexural modulus of greater than about 35,000 psi.

Multilayer dental appliances and related methods and systems

A multilayer sheet comprising first, second, and third layers is provided. The first layer consists of a co-polyester having an elongation at break of greater than 70%. The second layer consists of a thermoplastic polyurethane elastomer having an elongation at break of greater than 200% and a hardness of about 60 A to about 85 D. The first layer has a hardness greater than the hardness of the second layer. A mold is provided and the multilayer sheet is thermoformed over the mold to form a plurality of tooth-receiving cavities configured to receive and position a patient's teeth from a first arrangement toward a second arrangement. Excess material is trimmed from the thermoformed multilayer sheet to form the multilayer dental aligner.

Methods for making dental aligners from multilayer sheets

A multilayer sheet comprising first and second layers is provided. The first layer consists of a co-polyester. The second layer consists of a thermoplastic polyurethane elastomer having an elongation at break of greater than 200%, a hardness of 60A to 85D, an ultimate tensile strength of greater than about 5000 psi, and a light transmission between 400 nm and 800 nm of greater than about 75%. A mold is provided and the multilayer sheet is thermoformed over the mold to form a plurality of tooth-receiving cavities configured to receive and reposition a patient's teeth from a first arrangement toward a second arrangement. Excess material is trimmed from the thermoformed multilayer sheet to form a multilayer dental aligner.

Methods for making multilayer dental aligners

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

Multilayer polymer sheets

Growing community of inventors

Lenox, MA, United States of America

Craig Pehlert