GB1029168A - Improvements in or relating to embossing rolls - Google Patents

Abstract

1,029,168. Embossing surfaces. MODERN ENGRAVING & MACHINE CO. Sept. 10 1964, No. 37153/64. Heading B6C. An embossing roll bearing a plurality of areas, each having the same design is made by producing a photo-engraved cylindrical die 16, Fig. 2, of the design set in one such area and then employing the die to manufacture a mill 22, Fig. 3, which is subsequently utilized, as shown in Fig. 7, to " bump " engrave a cylinder 38 which has been photo-engraved in the same manner as the die 16, but has the required plurality of design bearing areas 40. Each design comprises a pictorial representation 12, Fig. 1, and three registration marks 14 which, in the finished roll, appear as indentations 44, Fig. 7. This female embossing roll is used to make a male embossing roll in the manner described in U.S.A. Specification 2,662,002, but as the protrusions on the male roll corresponding to the indentations 44 are not required in the final product in the marks 14 on the "original" design being provided only for registration purposes during the manufacture of the rollsthey are removed. In the " bump " engraving process the mill 22, Fig. 3, is rollingly rocked under pressure back and forth a number of times against each area 40 of the cylinder 38 after it is coated by an asphaltum base composition with the design and index mark mill protrusions 24, 26 in engagement with the like roll indentations 44, 42, Fig. 7. The cylinder areas removed by the mill are subsequently etched. In order to produce the necessary depth of indentation in the cylinder 38 more than one cycle of resist coating, rocking and etching may be effected.