Slide fastener and method of producing waterproof chain

A slide fastener comprising:

• a first waterproof stringer comprising a woven and/or knitted first fastener tape, a first coil element secured to a first side-edge portion of the first fastener tape, and a first waterproof film overlaid via a first adhesive on a tape top surface of the first fastener tape;
• a second waterproof stringer comprising a woven and/or knitted second fastener tape, a second coil element secured to a second side-edge portion of the second fastener tape, and a second waterproof film overlaid via a second adhesive on a tape top surface of the second fastener tape, the second side-edge portion opposing to the first side-edge portion;
• and
• a slider that moves forward to engage the first and second coil elements and moves rearward to disengage the first and second coil elements, wherein
• the first and second waterproof films have first and second film edges which are positioned over a space between the first and second opposing side-edge portions of the first and second fastener tapes,
• the first film edge supported by a first supporting portion made of the first adhesive solidified, the first supporting portion partially occupying the space between the first and second side-edge portions of the first and second fastener tapes, and the first supporting portion having a thickness greater than a thickness of the first film edge or greater than twice a thickness of the first film edge, and
• the second film edge supported by a second supporting portion made of the second adhesive solidified, the second supporting portion partially occupying the space between the first and second side-edge portions of the first and second fastener tapes, and the second supporting portion having a thickness greater than a thickness of the second film edge or greater than twice a thickness of the second film edge.