Forming articles and devices with carbon-coated metal particles
View Patent ↗A non-aqueous photocurable composition contains dispersed carbon-coated metal particles in an organic diluent in an amount of at least 10 weight %. The dispersed carbon-coated metal particles have a median diameter equal to or less than 0.6 μm, and are dispersed using a particle dispersing agent that has a weight average molecular weight (M w ) of at least 2,000 and up to and including 100,000 and comprises nitrogen-containing units. The median diameter of the dispersed particles is determined using a dynamic light scattering method. Moreover, when the non-aqueous composition contains up to and including 25 weight % of the dispersed carbon-coated metal particles, it exhibits no visual settling when subjected to a settling test of at least 24 hours at 20° C. Such non-aqueous photocurable compositions include photocurable components and are useful to prepare photocurable and photocured electrically-conductive patterns and layers in various articles, including touch screen devices having touch screen displays.
1. A method for providing a precursor article, the method comprising:
providing a continuous web of a transparent substrate,
on one or more portions on at least one supporting side of the continuous web, forming one or more photocurable patterns from a non-aqueous photocurable composition that comprises a photocurable component, an organic diluent, dispersed non-magnetic carbon-coated metal particles in an amount of at least 10 weight % based on the total weight of the non-aqueous photocurable composition, and a particle dispersing agent selected by a concentrated dispersant test from particle dispersing agents having a weight average molecular weight (Mw) of at least 2,000 and up to and including 100,000 and comprising nitrogen-containing units that are efficient in maintaining a median diameter of the dispersed non-magnetic carbon-coated metal particles within a range of less than 0.25 μm, the concentrated dispersant test being carried out by dispersing the non-magnetic carbon-coated metal particles at 50 weight % in 1-methoxy-2-propanol at a 20:1 weight ratio of the dispersed non-magnetic carbon-coated metal particles to the particle dispersing agent, the median diameter being determined using a dynamic light scattering method.
2. The method of claim 1 , further comprising:
photocuring the one or more photocurable patterns to form one or more photocured patterns on the one or more portions of the continuous web, each of which one or more photocured patterns comprises the dispersed non-magnetic carbon-coated metal particles as seed metal catalyst sites, and
electrolessly plating each of the one or more photocured patterns on the one or more portions of the continuous web with an electrically conductive metal.
3. The method of claim 2 , further comprising:
carrying out the forming, photocuring, and electrolessly plating features multiple times on multiple portions of the continuous web, which multiple portions are the same or different, using the same or different non-aqueous photocurable composition.
4. The method of claim 1 , for providing a plurality of precursor articles, comprising:
forming multiple photocurable patterns on multiple portions on one or both supporting sides of the continuous web by applying the non-aqueous photocurable composition to the multiple portions using one or more flexographic printing members,
advancing the continuous web comprising the multiple photocurable patterns to be proximate to an exposing radiation, and thereby forming multiple photocured patterns, and
winding up the continuous web comprising the multiple photocured patterns.
5. The method of claim 1 , wherein the substrate is a continuous polymeric web.
6. The method of claim 5 , wherein the substrate is a continuous polymeric web comprising poly(ethylene terephthalate).
7. The method of claim 1 , wherein the non-aqueous photocurable composition comprises dispersed non-magnetic carbon-coated silver particles or dispersed non-magnetic carbon-coated copper particles, or a mixture of both dispersed non-magnetic carbon-coated silver particles and dispersed non-magnetic carbon-coated copper particles.
8. The method of claim 1 , wherein the non-aqueous photocurable composition has a weight ratio of the particle dispersing agent to the dispersed non-magnetic carbon-coated metal particles of at least 1:100 and up to and including 30:100.
9. The method of claim 1 , wherein the particle dispersing agent has an M w of at least 2,000 and up to and including 50,000.
10. The method of claim 1 , wherein the non-aqueous photocurable composition further comprises dispersed carbon black in an amount of up to and including 20 weight %, based on the total weight of the non-aqueous photocurable composition.
11. The method of claim 1 , wherein the particle dispersing agent is an organic polymer that comprises units chosen from at least one of the following classes (i) through (iv):
(i) pyridine units;
(ii) imine units;
(iii) imide units; and
(iv) amine units.
12. The method of claim 1 , wherein the dispersed non-magnetic carbon-coated metal particles are dispersed non-magnetic carbon-coated silver particles that are present in the non-aqueous photocurable composition at a concentration of at least 15 weight % and up to and including 60 weight % based on the total weight of the non-aqueous photocurable composition, and the dispersed non-magnetic carbon-coated silver particles have a median diameter of less than 0.21 μm as determined using the dynamic light scattering method.
13. The method of claim 1 , wherein the photocurable component is a UV-curable component.
14. The method of claim 1 , wherein the photocurable component comprises one or more free-radically polymerizable materials and one or more free radical photoinitiators.
15. The method of claim 1 , wherein the dispersed non-magnetic carbon-coated metal particles have a median diameter of less than 0.2 μm as determined using the dynamic light scattering method.
16. The method of claim 1 , wherein the dispersed non-magnetic carbon-coated metal particles have a median diameter of less than 0.1 μm as determined using the dynamic light scattering method.