Short-chain fluorosurfactants with iodide additives for forming silver nanowire-based transparent conductive films
Disclosed herein are purified surfactant formulations including purified short-chain fluorosurfactant and iodide additive and a two-part coating kit having the same and a silver nanowire formulation.
1. A coating composition comprising:
conductive nanostructures; and
a purified surfactant formulation comprising:
a short-chain fluorosurfactant represented by Formula (I):
an impurity represented by Formula (II) at an amount of less than about 3% by weight of the short-chain fluorosurfactant,
and
an iodide additive providing iodide at an amount of about 0.5-2.5% of the short-chain fluorosurfactant,
wherein,
m is 0, 1, 2, 3, 4 or 5;
n is 1, 2, 3, or 4;
X is —O—; —S—; or a direct bond;
Y is hydrogen, —OH or fluoro;
Z is —CH 3 , —CH 2 F, —CHF 2 or —CF 3 ;
M + is Li + , Na + , K + , H + or NH 4 + ; and
R 1 , R 2 , R 3 , R 4 and R 5 , at each occurrence, are the same or different and independently fluoro or hydrogen.
2. The coating composition of claim 1 , wherein the short-chain fluorosurfactant represented by Formula (I) has no more than 6 fluoro-bearing carbons.
3. The coating composition of claim 1 , wherein X is a direct bond.
4. The coating composition of claim 1 , wherein Y is —OH.
5. The coating composition of claim 4 , wherein Z is —CF 3 .
6. The coating composition of claim 1 , wherein m is 6 and n is 2.
7. The coating composition of claim 1 , wherein the impurity represented by Formula (II) is less than about 0.4% of the short-chain fluorosurfactant.
8. The coating composition of claim 1 , wherein the iodide in the fluorosurfactant formulation is about 0.6-2.4% by weight of the short-chain fluorosurfactant.
9. The coating composition of claim 1 , wherein the conductive nanostructures comprise silver nanowires.
10. The coating composition of claim 9 , further comprising viscosity modifier, wherein a ratio of the silver nanowires and the viscosity modifier is in the range of about 0.00626 to about 5.
11. The coating composition of claim 9 , wherein the coating composition comprises silver ions at an amount of 0.005-0.02% per 1% of the silver nanowires by weight.
12. The coating composition of claim 11 , wherein the iodide ions at an amount of about equimolar of the silver ions.
13. The coating composition of claim 9 , wherein silver nanowires are no more than 30 nm in diameter, and are more than 5 μm long.
14. The coating composition of claim 1 , further comprising dispersant.
15. The coating composition of claim 1 , further comprising liquid carrier.
16. The coating composition of claim 15 , wherein the liquid carrier comprises water or water-miscible cosolvents.
17. A coating composition comprising:
from 0.05% to 1.4% by weight of conductive nanostructures;
from 0.02% to 4% by weight of a viscosity modifier;
from 94.5% to 99.0% by weight of a liquid carrier; and
from 0.0025% to 0.1% by weight of a purified surfactant formulation comprising:
a short-chain fluorosurfactant represented by Formula (I):
an impurity represented by Formula (II) at an amount of less than about 3% by weight of the short-chain fluorosurfactant,
and
an iodide additive providing iodide at an amount of about 0.5-2.5% of the short-chain fluorosurfactant,
wherein,
m is 0, 1, 2, 3, 4 or 5;
n is 1, 2, 3, or 4;
X is —O—; —S—; or a direct bond;
Y is hydrogen, —OH or fluoro;
Z is —CH 3 , —CH 2 F, —CHF 2 or —CF 3 ;
M + is Li + , Na + , K + , H + or NH 4 + ; and
R 1 , R 2 , R 3 , R 4 and R 5 , at each occurrence, are the same or different and independently fluoro or hydrogen.
18. The coating composition of claim 17 , wherein the impurity represented by Formula (II) is less than about 0.4% of the short-chain fluorosurfactant.
19. The coating composition of claim 17 , wherein the iodide in the fluorosurfactant formulation is about 0.6-2.4% by weight of the short-chain fluorosurfactant.
20. The coating composition of claim 17 , wherein the conductive nanostructures comprise silver nanowires.