Method for producing a watermark element, watermark element, and also applications
US8673114B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 2009 |
| Grant date | Mar 18, 2014 |
| Priority date | — |
| Expiry date | Nov 19, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24802
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
According to one aspect, the invention relates to a method for producing a watermark element (10) for forming a shadow watermark image in a substrate by means of dewatering of a fibrous suspension, wherein the watermark element (10) comprises a body with a relief side (12) having a relief (14) and a dewatering side (16) positioned opposite the relief side, perforations (18) being provided at least in the relief (14), a perforation (18) comprising a channel (20) with a channel inlet (21) at the relief side (12) and a channel outlet (22) at the dewatering side (16), which method includes the steps of forming perforations in a body in a mechanical manner and introducing a relief in the intended relief side, the perforations (18) being formed in such a way that the dewatering capacity, expressed as the open surface area of the channel inlet(s) per unit of surface area of the relief, is dependent on the height (h) of the channel inlet (21) with respect to the dewatering side (16), it being the case that the higher the height, the lower the dewatering capacity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.