Use of ionic liquids for the pretreatment of surfaces of plastics for metallization
Process for coating plastics with metals, wherein the plastics are pretreated with a composition comprising at least one salt having a melting point of less than 100° C. at 1 bar (hereinafter referred to as ionic liquid).
1. A process for coating a plastic with a metal, the process comprising:
contacting a plastic with a composition comprising an ionic liquid, to obtain a pretreated plastic; and
after the contacting, electrochemically depositing at least one layer of a metal on the pretreated plastic, to obtain a coated plastic,
wherein:
the ionic liquid is a salt having a melting point of less than 100° C. at 1 bar and comprises an ammonium cation; and
a content of the ionic liquid in the composition is more than 50% by weight.
2. The process of claim 1 , wherein the ionic liquid is a liquid at 21° C. at 1 bar.
3. The process of claim 1 , wherein a content of the ionic liquid in the composition is more than 80% by weight.
4. The process of claim 1 , wherein the composition further comprises water or an organic solvent.
5. The process of claim 1 , wherein the plastic is a thermoplastic polymer.
6. The process of claim 1 , wherein the plastic is a polyamide, a polyolefin, a polyester, a polyether, a polyacetal, a polycarbonate, a polyurethane, a polyacrylate, a polystyrene or a copolymer of styrene.
7. The process of claim 1 , wherein the metal is at least one selected from the group consisting of nickel, aluminum, copper, chromium, tin, zinc and alloys thereof.
8. The process of claim 1 , wherein the contacting is at a temperature of 30-120° C.
9. The process of claim 1 , wherein the plastic is polyoxymethylene.
10. The process of claim 1 , wherein the plastic is a styrene-acrylonitrile copolymer.
11. The process of claim 1 , wherein the plastic is an acrylonitrile-butadiene-styrene copolymer (ABS).
12. The process of claim 1 , further comprising, prior to the contacting, cleaning the plastic.
13. The process of claim 1 , further comprising, prior to the contacting, degreasing the plastic.
14. The process of claim 1 , further comprising, prior to the contacting, cleaning and degreasing the plastic.
15. The process of claim 1 , further comprising applying a metal nuclei, after the contacting and before the electrochemical depositing.
16. The process of claim 1 , further comprising, after the contacting, precoating the pretreated plastic with a first metal coating, to obtain a seed layer.
17. The process of claim 1 , wherein the ionic liquid is a salt having a melting point of less than 70° C. at 1 bar.