Erasable paper product
A paper product comprising a base sheet and a marking-erasable coating is disclosed. The base sheet can comprise a base-sheet core and a base-sheet coating. The marking-erasable coating is water soluble or water dispersible and can include, for example, various natural or modified starches applied at a coating weight sufficient to make the surface of the paper product erasable. The paper product can be substantially recyclable or substantially repulpable. Also described is a method for making the paper product.
1 . A paper product having a base sheet and a marking-erasable coating, where the marking-erasable coating is water-soluble or water dispersible.
2 . The paper product of claim 1 , where the paper product is substantially recyclable or substantially repulpable.
3 . The paper product of claim 1 , where the marking-erasable coating is substantially continuous.
4 . The paper product of claim 1 , configured so that liquid ink from a black dry erase marker can be applied to the surface of the paper product, allowed to dry, and then erased with a dry cloth, where the liquid ink has a marker density greater than about 0.5 after drying and a residual marker density less than about 0.1 after being erased.
5 . The paper product of claim 1 , where the marking-erasable coating comprises an ingredient selected from the group consisting of starch, cellulose, a charged polymer, a derivative thereof, and mixtures thereof.
6 . The paper product of claim 1 , where the marking-erasable coating comprises pearl corn starch, pea starch, ethylated starch, carboxyl methylated starch, cationic potato starch, styrene butadiene grafted starch, modified food grade tapioca starch, carboxymethylcellulose, hydroxyethylcellulose, sodium alginate, polyvinyl alcohol, or mixtures thereof.
7 . The paper product of claim 1 , where the marking-erasable coating comprises at least one starch.
8 . The paper product of claim 1 , where the marking-erasable coating comprises greater than about 50% starch by dry weight.
9 . The paper product of claim 1 , where the paper product has a Gurley density greater than about 1,000 seconds.
10 . The paper product of claim 1 , where the surface of the paper product has a Sheffield smoothness less than about 200 cubic centimeters per minute.
11 . The paper product of claim 1 , where the marking-erasable coating is present in an amount sufficient to make the paper product erasable.
12 - 13 . (canceled)
14 . The paper product of claim 1 , where the base sheet comprises:
a base-sheet core, comprising a network of fibers; and
a base-sheet coating, comprising a pigment and a binder.
15 - 16 . (canceled)
17 . The paper product of claim 14 , where the marking-erasable coating comprises less than about 30% pigment by dry weight.
18 . The paper product of claim 1 , where the base sheet comprises a base-sheet core and there is no base-sheet coating between the base-sheet core and the marking-erasable coating.
19 - 21 . (canceled)
22 . The paper product of claim 1 , where the marking-erasable coating has a substantially continuous surface that contains substantially no surface-exposed pigment particles.
23 - 24 . (canceled)
25 . A method for making a paper product, comprising applying a marking-erasable coating to a base sheet, where the marking-erasable coating is water-soluble or water dispersible.
26 . The method of claim 25 , further comprising calendering the paper product after applying the marking-erasable coating until the paper product has a Gurley density greater than about 1,000 seconds.
27 . The method of claim 25 , further comprising calendering the paper product after applying the marking-erasable coating until the paper product has a Sheffield smoothness less than about 200 cubic centimeters per minute.
28 - 29 . (canceled)
30 . The method of claim 25 , where the marking-erasable coating is applied at a coating weight sufficient to make the paper product erasable.
31 . (canceled)
32 . The method of claim 25 , where the base sheet comprises:
a base-sheet core, comprising a network of fibers; and
a base-sheet coating, comprising a binder.
33 . (canceled)
34 . The method of claim 25 , where the base sheet does not comprise a base-sheet coating and no base-sheet coating is applied before applying the marking-erasable coating.
35 . (canceled)
36 . A kit, comprising:
a paper product, comprising a base sheet and a marking-erasable coating, where the marking-erasable coating is water-soluble or water dispersible; and
a writing instrument that can be used to create erasable marks on the paper product.
37 . The kit of claim 36 , further comprising an eraser that can be used to erase marks made on the paper product by the writing instrument.
38 . A note paper product, comprising a sheet having a first surface and a second surface, where at least a portion of the second surface is covered with an adhesive material, the sheet comprises a base sheet and a marking-erasable coating, and the marking-erasable coating is water-soluble or water dispersible.