| 摘要 |
<p>All the layers are substantially larger than the size the finished circuit board is to be and selectively bonded and slotted in pre-selected locations, and maintained in this over-sized condition throughout the procedure in which holes for interconnections are drilled, and plated through with conductive material. Only after the plating procedure has been completed are the portions of the upper and lower rigid layers removed from locations above and below the appendage portions, thus allowing them to attain the desired, flexible condition. By keeping the rigid layers intact, the assemblage is maintained rigid during the plating, thereby avoiding work hardening of the flexible portions even without tools for restraining the flexible portions.</p> |
