Tape-mounted snap fastener having engagement and disengagement directionality

A tape-mounted snap fastener having engagement and disengagement directionality comprising:

• a male tape made of a cloth tape on which a plurality of synthetic resin male parts are molded and fastened at certain intervals,
• said male part comprising a base having a face side and a back side, an engagement socket in the base, an engagement protrusion having a first slanting surface and a second slanting surface and extending diagonally upwards at a slant angle in the direction of the engagement socket from the face side of the base, and a third slanting surface on the face side of the base within the engagement socket, which third slanting surface is parallel with the protrusion-forming first slanting surface, and
• a female tape made of a cloth tape on which a plurality of synthetic resin female parts are molded and fastened at certain intervals,
• said female part comprising a base having a face side and a back side, an engagement socket in the base, an engagement protrusion having a first slanting surface and a second slanting surface and extending diagonally downwards at a slant angle in the direction of the engagement socket from the face side of the base, and a third slanting surface on the face side of the base within the engagement socket, which third slanting surface is parallel with the protrusion-forming first slanting surface,
• whereby, when the male and female parts are engaged, said female part forms a space for housing the male part engagement protrusion, the first slanting surface of the female part and the first slanting surface of the male part mate with each other, the second slanting surface of the female part and the third slanting surface of the male part mate with each other, and the third slanting surface of the female part and the second slanting surface of the male part mate with each other.