Patent ID: 6450539
Filing Date: 2002-09-17
Classification: B43L,G09F

Abstract:
An erasable product comprising a base layer and an upper sheet extending over the base layer and the upper sheet having peripheral sides fixed in relation to the base layer, which upper sheet and base layer are in a first area sufficiently releasably adhesive together under pressure applied manually on the upper sheet to cause the upper sheet and the base layer to adhere in the localized region of said pressure but to allow the upper sheet to move sufficiently relative to the base layer to separate the upper sheet from the base layer when a user's finger or thumb is wiped across the top surface of the upper sheet, the upper sheet also extending in a second area over a wipe-start region adjacent the base layer in which the wipe-start region, the upper sheet, and the base layer are not adhesive together and over which wipe-start region a user's finger or thumb may be placed from which to begin said movement to separate the upper sheet from the base layer, the upper sheet also comprising a discontinuity in the upper sheet extending across at least a major portion of one dimension of the upper sheet in the plane of the upper sheet and having a generally convex shape in cross-section, said discontinuity in the upper sheet occupying a smaller area of the upper sheet than the wipe-start region and said discontinuity extending either across the wipe-start region adjacent said first area so that said discontinuity separates said first area and a part of the wipe-start region larger in area than said discontinuity, or in said first area adjacent said wipe-start region so that said discontinuity separates said first area and said wipe-start region, said upper sheet also providing a smooth and otherwise substantially wrinkle-free top surface to the product on either side of said discontinuity in said first area and said second area.