PCT No. PCT/GB96/00562 Sec. 371 Date Sep. 10, 1997 Sec. 102(e) Date Sep. 10, 1997 PCT Filed Mar. 11, 1996 PCT Pub. No. WO96/28610 PCT Pub. Date Sep. 19, 1996The present invention relates to a method for producing security paper which includes a security feature. The method comprises forming paper in a wet state, which paper incorporates on or more security features, applying to the paper a sizing agent, thereafter applying to one or both sides of the sized paper a coating comprising an unpigmented polyurethane. The unpigmented polyurethane may optionally comprise a functional additive provided that the presence of the functional additive does not increase the opacity of the paper by more than 1%. After the polyurethane has been applied the paper is dried. The coating composition provides a film, when cast on a glass surface, having a K+E,uml o+EE nig hardness of from 15 to 130 seconds.
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