ROUGH TACTILE RADIATION CURABLE COATING
A coating composition for creating a rough tactile surface on a substrate comprises a plurality of high aspect ratio flakes dispersed through a radiation-curable binder. The composition is can be employed in anilox and gravure printing systems incorporating doctor blades and like skimming units in which conventional tactile coatings cannot be successfully employed.
1 . A coating composition for creating a rough tactile surface on a substrate, comprising a plurality of high aspect ratio flakes dispersed through a radiation-curable binder.
2 . The coating of claim 1 , wherein the binder is UV, EB or LED curable.
3 . The coating of claim 1 , wherein the flakes a have a longest face dimension of from 25 to 400 microns and the aspect ratio of the flakes is from 2 to 31.
4 . The coating of claim 3 wherein the aspect ratio of the flakes is from 2 to 15.
5 . The coating of claim 1 , wherein the viscosity of uncured coating composition is from 200 to 5000 cps.
6 . The coating of claim 1 , wherein the binder comprises an acrylate oligomer, an acrylate monomer, and optionally at least one additive in the form of a wetting agent, defoamer, slip agent, stabilizer, dispersant, optical brightener or dye.
7 . The coating of claim 5 , wherein the flakes comprise between 5 and 50 weight percent of the coating composition.
8 . The coating of claim 5 wherein the flakes comprise between 15 and 30 weight percent of the coating composition.
9 . The coating of claim 1 wherein the flakes are of polymeric film.
10 . The coating of claim 8 wherein the flakes have a face shape selected from square, rectangle, hexagon, circle, diamond and star.
11 . The coating of claim 6 further comprising at least one machine-readable feature substance.
12 . A rough tactile construction, comprising a cured coating of claim 1 on a surface of a substrate.
13 . A method for applying a rough tactile surface composition to a substrate, comprising the steps of:
a. preparing a radiation-curable binder composition;
b. adding a plurality of high aspect ratio flakes to the binder composition to form a coating composition;
c. applying the coating composition through flexo or gravure application process having a metering apparatus;
d. transferring the coating composition onto the substrate whereby flakes extend upwardly and outwardly of the binder composition; and
e. curing the coating composition on the substrate whereby the flakes remain oriented upwardly and outwardly to form a tactile surface to the binder.
14 . The method of claim 12 wherein the flakes have a longest face dimension greater than a thickness of the binder on the substrate.
15 . The method of claim 12 wherein the metering apparatus includes a doctor blade.