摘要:
The present invention relates to a security paper that cannot be forged with respect to forgery attempts with non-aqueous solvents, characterized in that it comprises on its surface and/or in its bulk, clusters formed of elementary particles that are both insoluble in water and in solvents, amalgamated with an agglomerating agent that is also insoluble in water but almost instantaneously soluble in at least one non-aqueous solvent so as to release said elementary particles in the paper, which elementary particles are preferably less than 20 μm, and more preferably still less than 10 μm, they are colored and are advantageously intense pigment dyestuffs such as those used for producing inks or paints.
摘要:
The invention relates to an assembly including an article to be authenticated, an authentication composition and a member for applying the composition, capable of retaining said composition by capillarity, wherein the article to be identified contains a first reagent selected from nickel, copper, cobalt or iron derivatives, or from dithiooxamide or oxime derivatives capable of reacting with a second reagent of the authentication composition selected respectively from among dithioxmide or oxmime derivatives or from nickel, copper, cobalt or iron derivatives, so as to form a visible and permanent coloured mark.
摘要:
A composition of matter for surface sizing of paper and other cellulosic products. In particular, the composition is a styrene/acrylic acid ester copolymer latex made by emulsion copolymerization without surfactants.
摘要:
A security paper authenticating system comprises, in combination, a security paper carrying both starch and an iodate salt, typically potassium iodate, and an authenticating composition comprising an acidic solution of an iodide salt, typically potassium iodide, the system being such that on applying the authenticating composition to authentic security paper, as by a pen, brush or stamp pad, iodine is generated and a characteristic starch-iodine coloration is produced. The authenticating composition is preferably aqueous or part-aqueous, and is preferably made acidic by means of a weak organic acid such as tartaric acid. The authenticating composition preferably also contains an antioxidant such as ascorbic acid. The invention extends to the paper and the authenticating composition individually.
摘要:
This invention relates to paper-making and in particular to non-fluorescent forgery-proof safety paper which is characterized in that it comprises, on its surface and/or in its mass, a salt of cobalt(II) or (III), at least partially soluble in aqueous phase.
摘要:
A check paper is being described which is protected against falsifications and forgeries.Crushable micro capsules are being embedded in check paper which contain on one hand a leuco ink and on the other hand a color acceptor. The color acceptor can also be stored in the body of the paper without the use of micro capsules. The leuco ink and the color acceptor react together under color development or color changes if the micro capsules burst through imprinting or other local pressure application to the paper surface. Thus, a character written on the paper surface becomes visible within the body of the paper and cannot be forged anymore.