Binder

A method of manufacturing a binder, the method comprising:

• providing:
• an interior polymer layer;
• an exterior polymer layer;
• and
• a foamed polymer layer;
• cutting:
• the interior polymer layer to form a single continuous interior layer including a front cover interior layer, a spine interior layer, and a back cover interior layer;
• the interior polymer layer to form an interior opening through the front cover interior layer, a front cover interior opening through the front cover interior layer, a spine interior opening through the spine interior layer, and a back cover interior opening through the back cover interior layer;
• the exterior polymer layer to form a single interconnected exterior layer including a front cover exterior layer, a spine exterior layer, and a back cover exterior layer;
• the foamed polymer layer to form a front cover base plate;
• the foamed polymer layer to form an interior opening through the front cover base plate;
• and
• the foamed polymer layer to form a back cover base plate;
• stacking:
• the front cover base plate between the front cover interior layer and the front cover exterior layer;
• and
• the back cover base plate between the back cover interior layer and the back cover exterior layer;
• and
• sealing at least a portion of the single continuous interior layer and a portion of the single interconnected exterior layer together.