Security paper comprising localized areas with reduced thickness and opacity, and method for making same
AssigneeArjo Wiggins S.A.
InventorsPierre Doublet, Yves Douesneau, Jean-Paul Menez
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Abstract
A method for making a paper sheet comprising at least one region which is thinner than the rest of the sheet. According to the method, a first paper layer (3) is formed on a wire in a first wet end of a paper-making machine, a second paper layer (5) is formed on a wire in a second wet end of the paper-making machine, one of the two paper layers has a number of localized tinner regions (8) so that the thickness (e2) of said paper layers in said regions is up to 50% less than the thickness (et) of the rest of the sheet, and the two layers are joined together and dried. The resulting paper may be used in banknotes or checks.
Claims20
A process for manufacturing a sheet of paper which includes at least one region having reduced thickness relative to the thickness of the rest of the sheet, characterized in that a first layer of paper (3) is formed on a wire of a first wet end of a paper-making machine, a second layer of paper (5) is formed on a wire of a second wet end of a paper-making machine, one of the two layers of paper having at least some local regions (8) of less thickness, so that the thickness (e2) of the two layers of paper in said regions is up to 80% relative to the thickness (et) of the rest of the sheet, the two layers are joined directly together and dried.
A sheet of security paper which includes at least one area of reduced opacity (3,20) of at least 0.4 cm2 having a uniform reduced opacity less than the opacity of the rest of the sheet wherein the sheet is a two-ply sheet (16, 17) including one ply (17) which comprises at least one area whose thickness is nil and wherein the two plies are directly joined together.
Dependencies are inferred from the claim text.