Patent attributes
Collapsible heatable liquid containers having three non-inverting tiers and two inverting tiers interposed between the non-inverting tiers. The non-inverting tiers are typically formed of a stiff (i.e., stiff or rigid) material that is different from the material of the inverting tiers, which is typically a resilient polymer such as a thermoplastic elastomer or silicone. The bottom non-inverting tier is typically formed of a material suitable for inductive, contact, and flame heating, such as stainless steel. The container may be a liquid vessel suitable for drinking, beverage heating and serving, or cooking, such as a drinking bottle or kettle. A bottle may include an attached cap that engages the top tier to close the bottle, and a kettle may include a pour spout connected to the middle or top tier.