QLPF/QPHF series all-fluoropolymer pleated filter cartridge, the fitler membrane is made of natural strong hydrophobic PTFE stretched membrane, or modified PTFE membrane(which can filter aqueous solutions), which has strong corrosion resistance and oxidation resistance. The skeleton and diversion structure are made of fluorine material, which is made by hot melt welding, without any adhesive, without medium shedding, and has the characteristics of high flux, high retention, excellent chemical compatibility, and oxidation resistance. This series of filter elements are wildely used in chemical filtration in chemical, semiconductor, pharmaceutial and other processes, such as etching solution, photoresist, developer and other complex chemicals and other strong corrosive, oxidative, high temperature and other liquids and gases filter.