Patient interface

A patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to a patient's airways including at least entrance of a patient's nares, wherein the patient interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout a patient's respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing;

• said patient interface comprising:
• a plenum chamber at least partially forming a cavity pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber forming a non-patient contacting structure on an anterior side of the cavity and including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient;
• and
• a seal-forming structure having a textile membrane constructed and arranged to form a seal with a region of the patient's face surrounding an entrance to the patient's airways, said textile membrane having at least one hole formed therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to the patient's nares, the seal-forming structure constructed and arranged to maintain said therapeutic pressure in the cavity throughout the patient's respiratory cycle in use,
• wherein the textile membrane comprises a textile material and a membrane layer applied thereto to make the textile material substantially air impermeable, the textile material being a weft knit textile,
• wherein the seal-forming structure includes a flexible support structure to support the textile membrane, the support structure comprising silicone and being connected to the plenum chamber, the support structure being stiffer than the textile membrane,
• wherein the plenum chamber comprises silicone and the support structure is integrally formed with the plenum chamber as a one-piece structure,
• wherein the textile membrane is attached to the support structure along an outer perimeter of the textile membrane such that textile membrane extends radially inwardly beyond the support structure,
• wherein, in use, the textile membrane is configured to press against the patient's face such that the patient's nose is not received in the cavity, and
• wherein the textile membrane has a dome shape in a corner region of the textile membrane configured to seal against the patient's subalare, and a saddle shape at a lower central region of the textile membrane configured to seal against the patient's subnasale.