Ionic liquid release coat for use in metal flake manufacture
A method of producing metal flakes ( 72 ′) is provided. The method includes: applying a layer of ionic liquid ( 70 ) to a substrate ( 24 ); forming a layer of metal ( 70 ) on the substrate ( 24 ) over the ionic liquid ( 70 ); and removing the layer of metal ( 70 ) from the substrate ( 24 ).
1. A method of producing metal flakes, said method comprising:
applying a layer of ionic liquid to a substrate;
forming a layer of metal on the substrate over the ionic liquid; and
removing the layer of metal from the substrate.
2. The method of claim 1 , wherein said ionic liquid comprises:
at least one of triisobutylmethyl tosylate, tributylethylphosphonium diethylphosphate, trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, and 1-methyl-3-hexadecylimidazolium tosylate.
3. The method of claim 1 , wherein forming the layer of metal includes:
vapor depositing the layer of metal on the substrate over the ionic liquid in a vacuum chamber.
4. The method of claim 3 , wherein the layer of ionic liquid is applied to the substrate in the vacuum chamber.
5. The method of claim 3 , wherein the layer of ionic liquid is applied to the substrate outside the vacuum chamber.
6. The method of claim 1 , wherein the layer of ionic liquid is applied by one of reverse-roll coating, gravure coating, flexographic coating and vapor deposition.
7. The method of claim 1 , wherein the substrate comprises an outer rotating surface of a drum.
8. The method of claim 1 , wherein the substrate comprises a flexible polymer carrier.
9. The method of claim 8 , wherein removing the layer of metal from the substrate comprises at least one of shaking or vibrating the carrier.
10. The method of claim 1 , wherein the layer of metal is removed from the substrate by mechanical abrasion with a tool.
11. The method of claim 1 , wherein removing the layer of metal from the substrate at least partially breaks the layer of metal into flakes.
12. The method of claim 1 , further comprising:
collecting the flakes in a container, said container further holding an amount of non-volatile fluid sufficient to pacify the collected flakes.
13. The method of claim 12 , wherein the non-volatile fluid includes at least one of ionic liquid and oil.
14. The method of claim 1 , wherein said metal comprises:
at least one of aluminum, copper, silver, gold and indium tin oxide.
15. The method of claim 1 , wherein said ionic liquid comprises trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate, and the metal layer comprises aluminum.
16. The method of claim 1 , wherein said ionic liquid comprises 1-methyl-3-hexadecylimidazolium tosylate, and the metal layer comprises copper.
17. A metal flake made by a method comprising:
applying a layer of ionic liquid to a substrate;
forming a layer of metal on the substrate over the ionic liquid; and
removing the layer of metal from the substrate,
wherein the metal flake comprises a coating layer covering at last a part of a surface of the metal flake, the coating layer comprising an ionic liquid or fluid prepared from,
(a) one or more cations selected from the group consisting of imidazolium; phosphonium; ammonium; pyrazolium; pyridinium; pyrrolidinium; sulfonium; and cationic polymers;
wherein the cationic polymers, if present, are formed from one or more components selected from the group consisting of 4-chloromethylstyrene, 2-chloroethyl methacrylate, 2-chloroethyl acrylate, 4-chloro-1-butene, allyl chloride and allyl bromide reacted with butyl imidazole; and
(b) one or more anions selected from the group consisting of bromide, nitrate, hexafluorophosphate, tetrafluoroborate, tosylate, brosylate, dialkyl phosphate, dialkyl phosphinate, bis(trifluoromethylsulfonyl)imide, triflate, and bisulfate,
wherein the flake has a particle size from about 4 to about 12 microns.
18. A dispersion comprising a metal flake prepared by a method comprising:
applying a layer of ionic liquid to a substrate;
forming a layer of metal on the substrate over the ionic liquid; and
removing the layer of metal from the substrate,
wherein the dispersion comprises,
(a) 2 to 20 weight percent of the metal flake, on a basis of total weight of
the dispersion;
(b) 0.1 to 5 weight percent of at least one ionic liquid, on a basis of total weight of the dispersion; and
(c) 75 to 97 weight percent of one or more solvents,
on a basis of total weight of the dispersion.
19. The metal flake of claim 17 , wherein the imidazolium cation is
wherein R 1 and R 2 are each independently selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
20. The metal flake of claim 17 , wherein the phosphonium cation is ⊕ P(R 1 R 2 R 3 R 4 ), wherein R 1 , R 2 , R 3 and R 4 are each independently selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
21. The metal flake of claim 17 , wherein the ammonium cation is
wherein R 1 , R 2 , R 3 and R 4 are each independently selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
22. The metal flake of claim 17 , wherein the pyrazolium cation is
23. The metal flake of claim 17 , wherein the pyridinium cation is
wherein R 1 is selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
24. The metal flake of claim 17 , wherein the pyrrolidinium cation is
wherein R 1 and R 2 are each independently selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
25. The metal flake of claim 17 , wherein the sulfonium cation is
wherein R 1 , R 2 , R 3 and R 4 are each independently selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
26. The metal flake of claim 17 , wherein the cationic polymer comprises poly [1-(4-vinylbenzyl)-3-butylimidazolium].
27. The metal flake of claim 17 , wherein the cationic polymer comprises:
28. The metal flake of claim 17 , wherein the cationic polymer comprises poly [2-(1-butylimidazolium-3-yl)ethylmethacrylate].
29. The metal flake of claim 17 , wherein the cationic polymer comprises:
30. The metal flake of claim 17 , wherein the dialkyl phosphate anion is
wherein R 3 is selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
31. The metal flake of claim 17 , wherein the dialkyl phosphinate anion is
wherein R 3 is selected from hydrocarbons composed of 40 carbons or less with or without one or several heteroatoms of N, O, S and P and with or without one or several aromatic residue groups.
32. The metal flake of claim 17 , wherein the ionic liquid or fluid comprises:
at least one of triisobutylmethyl tosylate, tributylethylphosphonium diethylphosphate, trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, and 1-methyl-3-hexadecylimidazolium tosylate.
33. The metal flake of claim 17 , wherein the ionic liquid comprises trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate, and the metal layer comprises aluminum.
34. The metal flake of claim 17 , wherein the ionic liquid comprises 1-methyl-3-hexadecylimidazolium tosylate, and the metal layer comprises copper.
35. The metal flake of claim 17 , wherein the coverage density of the coating layer is about 0.1 to about 0.0034 grams m −2 .
36. The metal flake of claim 17 , wherein the metal flake comprises aluminum, copper, silver, chromium, nichrome, tin, zinc, indium, indium tin oxide, zinc sulfide, or alloys thereof.
37. The metal, flake of claim 17 , wherein the flake has a thickness of about 150 to about 250 angstroms.
38. The metal flake of claim 17 , wherein the metal flake comprises alternating layers of coating and metal film.
39. The dispersion of claim 18 , wherein said metal comprises:
at least one of aluminum, copper, silver, gold and indium tin oxide.
40. The dispersion of claim 18 , wherein the amount of ionic liquids is between 2 and 35 weight percent, based on the weight of the metal flakes.
41. The dispersion of claim 18 , wherein the ionic liquid comprises:
at least one of triisobutylmethyl tosylate, tributylethylphosphonium diethylphosphate, trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, and 1-methyl-3-hexadecylimidazolium tosylate.
42. The dispersion of claim 18 , wherein said ionic liquid comprises trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate, and the metal layer comprises aluminum.
43. The dispersion of claim 18 , wherein said ionic liquid comprises 1-methyl-3-hexadecylimidazolium tosylate, and the metal layer comprises copper.
44. The dispersion according to claim 18 , wherein the dispersion further comprises another non-volatile fluid.
45. The dispersion according to claim 44 , wherein the non-volatile fluid comprises oil.
46. A metal flake made by a method comprising:
applying a layer of ionic liquid to a substrate;
forming a layer of metal on the substrate over the ionic liquid; and
removing the layer of metal from the substrate,
wherein the metal flake a coating layer covering at last a part of a surface of the metal flake, the coating layer comprising an ionic liquid or fluid prepared from,
(a) one or more cations selected from the group consisting of imidazolium;
phosphonium; ammonium; pyrazolium; pyridinium; pyrrolidinium; sulfonium; and cationic polymers;
wherein the cationic polymers, if present, are formed from one or more components selected from the group consisting of 4-chloromethylstyrene, 2-chloroethyl methacrylate, 2-chloroethyl acrylate, 4-chloro-1-butene, allyl chloride and allyl bromide reacted with butyl imidazole; and
(b) one or more anions selected from the group consisting of bromide, nitrate, hexafluorophosphate, tetrafluoroborate, tosylate, brosylate, dialkyl phosphate, dialkyl phosphinate, bis(trifluoromethylsulfonyl)imide, triflate, and bisulfate,
wherein the ionic liquid or fluid comprises at least one of triisobutylmethyl tosylate, tributylethylphosphonium diethylphosphate, trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, and 1-methyl-3-hexadecylimidazolium tosylate.
47. A metal flake made by a method comprising:
applying a layer of ionic liquid to a substrate;
forming a layer of metal on the substrate over the ionic liquid; and
removing the layer of metal from the substrate,
wherein forming the layer of metal includes vapor depositing the layer of metal on the substrate over the ionic liquid in a vacuum chamber.