Patent GB-190513396-A (GB)
Title: Improvements in the Manufacture of Metal Rolls for Printing or Embossing purposes
Inventor: DREAPER WILLIAM PORTER
Filed: 1905-06-29
Granted: 1906-06-28
Abstract: 13,396. Dreaper, W. P. June 29. Embossing; printing surfaces and rollers; stencils &c. -Relates to the production of metal rolls which are either the duplicate or the "reverse" of a surface bearing a design engraved by hand or otherwise ; also to the production of stencil shields. Such rolls are suitable for embossing leather, plushes, velvets, leathercloth, wall papers and decorations, floorcloth, &c., and for printing textile and other materials. The rolls may be prepared in pairs so as to work together for embossing purposes. A metal mandrel is coated with wax or other suitable material, and is rotated in contact with the roll or flat surface bearing the design, means being provided for gradually increasing the pressure between the two surfaces. The wax surface bears the design in reverse, and, after its surface has been cooled with plumbago &c., it is immersed in an electro-typing bath and a shell of copper &c. deposited upon it. In order to facilitate the final stripping off of this metal mould from the roll deposited inside it, the wax roll A has a safe-edge B, B<1> of wax at each end, and when the mould has been deposited to about half its final thickness " stopping off " material is placed along a number of lines C joining the safeedges B, B<1>. Thus, after the mould has been fully deposited, the lines of weakness C are left for stripping off the mould, when required, from the roll. By another method, the mould is deposited to its full thickness but is afterwards dissolved away along the lines of weakness. The wax is next removed, and, the roll having been deposited in the mould, the latter may be removed and the inner surface of the roll turned up true for the reception of a spindle. In cases where the reproduced roll is to be run with the original roll for embossing purposes, the mould is coated with metal to a sufficient thickness on its interior and the roll deposited in this modified mould. This additional thickness may or may not be part of the original mould and may be stripped at the same time or separately. The effect of this is to leave a clearing space between the designs on the two rolls, and it varies for different thicknesses of material to be embossed. When the design to be reproduced is on a soft flat surface, a plaster cast of it is taken and from an electrotype or cast of the latter the roll is reproduced. It may be desirable, when producing duplicates of the original roll, to prepare first a flat wax surface, then a plaster cast of this, and from a type made of the latter to prepare the duplicate rolls. A duplicate roll may be prepared directly by coating the interior of a cylioder with wax or the like, rotating the original roll in contact therewith and then depositing the roll in the wax mould. By treating the surface of the wax mould only where metal is to be deposited, circular stencil shields may be produced in cases when the colour is applied by spraying. Two rolls may be run together so as to print and emboss simultaneously, the ink being applied by one of the rolls. When printing with more than one colour, parts of the wax design are scraped away so that only the desired parts of-the final roll will print its particular colour.