| 摘要 |
A lithographic printing process wherein an illuminated image on a document is scanned in a series of parallel sweeps with a photocell, applying an electric wave signal to a magnetic recording head with the amplitude of said signal determined by the output of the photocell and a function of the optical density of the image being scanned. The magnetic head has a width of from about 0.5 mils to about 5 mils and traverses a magnetic recording medium in a series of aligned parallel paths analogous to those scanned by the photocell to form a latent magnetic image in the magnetic recording medium, which image is a replica of the image being scanned. The horizontal spatial frequency is from about 200 to 1000 cycles/inch. The thus formed latent magnetic image is decorated with an oleophilic magnetic toner. The oleophilic magnetic image is transferred under pressure to a smooth heated lithographic substrate. If necessary, the toner is further heated to effect complete coalescence thereof. The thus formed lithographic printing plate is then used for lithographic printing.
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