Radio frequency weldable multi-layer tubing and method of making the same
Inventors
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-10131109-B2
Publication Date
2018-11-20
Expiration Date
Abstract
A RF weldable tubing is provided. The tubing has inner layer including a PVDF copolymer, or an ethylene alpha-olefin homopolymer, or an ethylene alpha-olefin polymer that may include a grafted polyethylene. The tubing may have an inter gas barrier layer sandwiched between the outer layer and an outermost layer including a TPU copolymer. The inter gas barrier layer may include an EVOH copolymer. A method of making such a tubing is also provided.
Core Innovation
The invention describes RF-weldable multilayer tubing for pharmaceutical fluid paths in which an inner layer comprises a polyvinylidene fluoride (PVDF) copolymer. The PVDF copolymer is positioned to enable radio frequency (RF) activity associated with dielectric loss factor (DLF), and it is constructed as an inner layer of the tubing. The tubing further includes a gas barrier layer in the multilayer structure.
A first outer layer comprising a polyester-based thermoplastic polyurethane (TPU) copolymer is directly laminated to the inner layer. This first outer layer is between the gas barrier layer and the inner layer, establishing a specific laminated arrangement of the PVDF copolymer inner layer, the gas barrier layer, and the TPU copolymer outer layer. The structure is designed so that RF welding is enabled by the PVDF copolymer or by an RF-weldable inner layer adjacent to RF-susceptible TPU.
The gas barrier layer is described as being optionally formed from inter gas barrier layers including EVOH copolymer material such as ethylene vinyl acetate-vinyl alcohol (EVOH). Optional additional layer constructions are described, including examples of different layer counts and configurations that include adhesive tie layers between named layers. Comparative examples are described to show DLF and RF weldability versus SEBS monolayers, with performance evaluation including DLF testing and seam peel strength.
Claims Coverage
The provided claim set includes two independent claims, each directed to a multilayer tubing architecture with a PVDF copolymer layer and polyester-based TPU copolymer layer, with additional claimed refinements in dependent claims regarding gas barrier layers, adhesives, and PVDF comonomer or grafted polymer selections. Overall, the inventive features center on the specific PVDF copolymer inner/first layer, the laminated relationship to a polyester-based TPU copolymer outer/second layer, and the presence and/or positioning of a gas barrier layer, including EVOH.
PVDF copolymer inner layer with laminated polyester-based TPU outer layer between PVDF and gas barrier
A tubing comprising an inner layer comprising a polyvinylidene fluoride (PVDF) copolymer, a gas barrier layer, and a first outer layer comprising a polyester-based thermoplastic polyurethane (TPU) copolymer, where the first outer layer is directly laminated to the inner layer and is between the gas barrier layer and the inner layer.
PVDF copolymer first layer directly attached to polyester-based TPU copolymer second layer
A tubing comprising a first layer comprising a polyvinylidene fluoride (PVDF) copolymer and a second layer directly attached to the first layer, where the second layer comprises a polyester-based thermoplastic polyurethane (TPU) copolymer.
Across the two independent claims, the core claimed coverage is a multilayer tubing structure that uses a PVDF copolymer layer together with a polyester-based thermoplastic polyurethane copolymer layer, with direct lamination/direct attachment between them. The claim set further supports dependent refinements that add a gas barrier layer, and can include adhesive tie layers and additional intermediate or outer layers.
Stated Advantages
RF weldability and DLF evaluation are described in the document through comparative example data versus SEBS monolayers.
Improved material performance characteristics are described, including clarity, sterilization resistance, and low leachables and extractables.
Documented Applications
Pharmaceutical fluid paths.
Interested in licensing this patent?