| 摘要 |
1,080,107. Magnetic storage apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. Nov. 3, 1965 [Dec. 30, 1964], No. 46487/65. Heading H3B. [Also in Divisions B6, G5 and H1] A method of producing a printed circuit on a surface comprises the steps of generating a magnetic line replica of the pattern on a magnetizable support, covering the support with an electrically insulating layer and developing the replica through contact with fine magnetic particles. As shown, Fig. 1, a probe 14 is used to draw a pattern of very fine magnetized lines 30 on a coating 12 of magnetic oxide on a plastic base 10. The coating 12 is covered with an electrically insulating layer 32, Fig. 2 (not shown), prior to development by immersion in a magnetic colloid bath. After development the circuit pattern is plated by either an electroless or electroplating operation the plating metals being copper, gold or silver. The insulating layer bearing the plated pattern may then be stripped from the oxide-coated plastic base. Further copies of the printed circuit may subsequently be obtained from the patterned base through the application of the above method. In a further example of the method a memory plane of the type used in magnetic storage memories for data processing machines is produced. A magnetic oxide coated plastic tape has placed upon the oxide layer an array of thin film magnetic dots in horizontal rows and vertical columns. Next, parallel lines are " written " in the magnetic oxide coating by passing a probe 14 along the tape to cross diametrically over the spots constituting the different horizontal rows. An insulating layer of evaporated silicon monoxide is then placed over the imaged dots and development is effected in a magnetic colloid. The lines are then plated prior to complete demagnetization in an A.C. field. The probe 14 is then used to " write " continuous parallel lines over the dots in the vertical columns before coating the dotted surface, by evaporating on to it silicon monoxide. The vertical lines are then developed in a magnetic colloid and finally plated prior to demagnetization. |
