HP Deskjet 6620 Color Inkjet Printer - Manual (Page 149)

Returned cartridges are separated for purification into raw materials for use in other
industries to manufacture new products. Examples of products made from recycled
HP print cartridge materials include automobile parts, trays used in microchip
fabrication processes, copper wire, steel plates, and the precious materials used in
electronics. Depending on the model, HP is able to recycle up to 65% of the print
cartridge by weight. The remaining parts that cannot be recycled (ink, foam, and
composite parts) are disposed of in an environmentally responsible manner.
HP Deskjet 6600 series printer User's Guide
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