TRANSPARENT POLYMER HARDCOATS WITH ANTIMICROBIAL EFFICACY
Transparent polymeric hardcoats with antimicrobial efficacy are described along with compositions for preparing the hardcoats. The transparent polymeric hardcoats at appropriate thicknesses can provide optical properties of high optical transmission, low haze and high clarity, and are suitable for use in electronic displays designed for commercial applications intended for high consumer use. Touch screens having the transparent polymeric hardcoats are also described.
1 . A coating composition comprising:
from about 0.025 wt % to about 90 wt % polymeric precursor,
from about 0.005M to about 1M antimicrobial metal salt, and
organic solvent.
2 . The coating composition of claim 1 , the antimicrobial metal salt comprising Ag + .
3 . The coating composition of claim 1 , the antimicrobial metal salt comprising Cu +2 .
4 . The coating composition of claim 1 , the antimicrobial metal salt comprising copper (II) nitrate, silver trifluoroacetate, silver tetrafluoroborate, silver hexafluoroantimonate or combinations thereof.
5 . The coating composition of claim 1 , the antimicrobial metal salt comprising copper (II) hexafluoroacetylacetonate.
6 . The coating composition of claim 1 , the polymeric precursor comprising UV curable acrylates.
7 . The coating composition of claim 1 , the polymeric precursor comprising urethane oligomers having acrylate functionality.
8 . The coating composition of claim 1 , the polymeric precursor comprising diglycidyl ethers of alkyl glycols.
9 . The coating composition of claim 1 , the polymeric precursor being free of aromatic groups.
10 . The coating composition of claim 1 , the organic solvent comprising aromatic solvents, alkanes, alcohols, ketones, esters, ethers, or mixtures thereof.
11 . The coating composition of claim 1 , further comprising silica nanoparticles.
12 . The coating composition of claim 1 , further comprising nanodiamonds.
13 . A transparent optical film comprising:
an antimicrobial hardcoat layer disposed on a transparent substrate, wherein the antimicrobial hardcoat layer comprises antimicrobial metal ions.
14 . The transparent optical film of claim 13 , the transparent substrate comprising a polyimide.
15 . The transparent optical film of claim 13 , the antimicrobial hardcoat layer further comprising from about 0.001 wt % to about 1 wt % nanoparticles.
16 . The transparent optical film of claim 13 , an outermost surface of the antimicrobial hardcoat layer exhibiting a water contact angle of at least about 112.5°.
17 . The transparent optical film of claim 13 , the hardcoat layer having a thickness of from about 2.5 microns to about 50 microns.
18 . The transparent optical film of claim 13 , having a b* no more than about 1.5, total transmittance of at least about 85%, and a haze value of no more than about 1.0%.
19 . The transparent optical film of claim 13 wherein the antimicrobial metal ions comprise copper (+2) ions.
20 . The transparent optical film of claim 13 wherein the animicrobial hardcoat layer comprises from about 0.02 wt % to about 10 wt % antimicrobial metal ions.
21 . A touch screen comprising:
a substrate;
a touch sensor supported by the substrate, and
an antimicrobial hardcoat layer disposed over and substantially covering the touch sensor, wherein the antimicrobial hardcoat layer comprises antimicrobial metal ions.