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US 6,159,585 AGranted
Security paper
AssigneeGeorgia-Pacific Corporation
InventorDavid A. Rittenhouse
Life of this patent
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AssigneeGeorgia-Pacific Corporation
InventorDavid A. Rittenhouse
Estimating the term…
A security paper indicates exposure to a solvent by a solvent resistant color signal. A metal mordant dye first co-reactant and a mordant dye second co-reactant form an organic solvent-insoluble colored reaction product when the paper is washed with an organic solvent. The metal mordant dye first co-reactant and a mordant dye second co-reactant are chemically isolated from each other so as to prevent the coordinate covalent bond from forming until the paper is washed with an organic solvent. The chemical isolation can be effected by encapsulation or other physical separation of the co-reactants. The organic solvent-insoluble colored reaction product, once formed, remains entrapped in the web when the paper is washed with an organic solvent. The chemical isolation prevents the organic solvent-insoluble colored reaction product from forming upon the application of pressure alone to the paper.
A security paper which forms an indelible color when contacted with an organic solvent comprising a web of cellulosic fibers, said web containing a metal mordant dye first co-reactant in particulate form chemically isolated from a mordant dye second co-reactant in particulate form, said mordant dye second co-reactant forming a coordinate covalent bond with said metal mordant dye first co-reactant to produce an organic solvent-insoluble colored reaction product when the paper is washed with an organic solvent, said chemical isolation preventing said coordinate covalent bond from forming until the paper is washed with an organic solvent and said organic solvent insoluble colored reaction product remaining entrapped in the web when the paper is washed with an organic solvent, wherein said organic solvent-insoluble colored reaction product does not form upon the application of pressure alone to said paper.
A security paper which forms an indelible color when contacted with an organic solvent comprising a web of cellulosic fibers, said web containing a metal mordant first co-reactant in particulate form chemically isolated from a mordant dye second co-reactant in particulate form, wherein one of said metal mordant first co-reactant and said mordant dye second co-reactant is attached to said cellulosic fibers, wherein said mordant dye second co-reactant forms a coordinate covalent bond with the metal mordant first co-reactant to produce an organic solvent-insoluble colored reaction product when the paper is washed with an organic solvent, said chemical isolation preventing said coordinate covalent bond from forming until the paper is washed with an organic solvent, wherein said organic solvent-insoluble colored reaction product remains entrapped in the web when the paper is washed with an organic solvent, and wherein said organic solvent-insoluble colored reaction product does not form upon the application of pressure alone to said paper.
Dependencies are inferred from the claim text.