| 摘要 |
<p>1,047,413. Printing processes. SALVAT EDITORES S.A. Feb. 9, 1965 [Feb. 15, 1964], No. 5672/65. Heading B6C. Four-colour printing is effected with three printing plates by forming each plate with an image area or areas which superimpose in the printed end product to thereby form the fourth colour. In the described embodiment a copy sheet receives successive impressions from blue, yellow and red inked printing plates, a required fourth colour, black, being obtained in the desired areas by the superimposition of the three colours. Photo-mechanical methods may be employed to image the three plates and the printing process employed may be letterpress, offset-lithe or photogravure. It is also possible to use more than three plates and achieve a combination of colours which exceeds by more than one colour the number of plates employed.</p> |
