Method for manufacturing IC card substrate

A method of making an IC card substrate of ABS plastic material, the substrate including oppositely oriented faces spaced apart by a thickness of the substrate, an IC module receiving recess in one of the faces and an IC chip recessed section within the recess extending towards the other one of the faces and forming a recess section bottom surface spaced from the other one of the faces by no more than about 100 .mu.m, the method comprising the steps of providing a mold having a cavity for molding the substrate, providing a reciprocable core pin in the mold having a cross-section corresponding to a cross-section of the recessed section and in alignment with the recessed section;

• partially advancing the core pin into the cavity so that a free end of the core pin is spaced from the other face a distance greater than 100 .mu.m;
• injecting the ABS material in its fluid state into the cavity and filling the cavity therewith;
• thereafter further moving the core pin into the cavity until its free end is spaced from the other face of the substrate no more than about 100 .mu.m;
• and hardening the ABS material.

A method of making a substrate for a substantially rectangular IC card having opposing faces spaced apart by a thickness of the card, a pair of spaced-apart, longitudinal edges and a pair of spaced-apart, short edges, and a recess for an IC chip, the method comprising the steps of providing a mold having a cavity conforming in size to the substrate and defining correspondingly long and short cavity sides which intersect at cavity corners;

• providing a reciprocable core pin in the mold a free end of which is extendable into the cavity;
• injecting a fluid, hardenable plastic material into the cavity;
• in the cavity flowing the injected material generally diagonally from an edge of the cavity proximate one of the cavity corners in a generally diagonal direction towards a diagonally opposite corner of the cavity to thereby molecularly align the fluid plastic material in the diagonal direction;
• prior to completely filling the cavity with the plastic material advancing the core pin into the cavity so that the free end of the core pin extends into the cavity a distance less than a desired depth of the recess;
• thereafter sequentially completing the injection step, further advancing the core pin into the cavity to the desired recess depth and hardening the plastic material;
• whereby a molecular alignment of the plastic material in the diagonal direction strengthens the substrate and prevents its breakage when bent about an axis of the substrate.