Silver-containing electrically-conductive compositions
An electrically-conductive composition essentially has (a) an electrically-conductive material consisting essentially of silver nanoparticles that have a d50 of less than or equal to 60 μm and a d90 of less than or equal to 500 μm; (b) particles having a Young's modulus that is different from the Young's modulus of the (a) electrically-conductive material by at least 10%, which (b) particles have a d50 of 500 nm to 300 μm and a polydispersity coefficient of less than or equal to 3; (c) a binder material that is non-electrically-conductive; and (d) a solvent medium in an amount of less than or equal to 90 weight %, based on the total composition weight, which solvent medium is at least 50 weight % water. The weight ratio of the (b) particles to the (a) electrically-conductive material is at least 0.01:1 and up to and including 7:1.
1. A composition consisting essentially of:
(a) an electrically-conductive material consisting essentially of silver nanoparticles that have a d50 of less than or equal to 60 μm and a d90 of less than or equal to 500 μm;
(b) particles having a Young's modulus that is different from the Young's modulus of the (a) electrically-conductive material by at least 10%, and which (b) particles have a d50 of at least 500 nm and up to and including 300 μm and a polydispersity coefficient that is less than or equal to 3;
(c) a binder material that is non-electrically-conductive and comprises one or more polyurethanes, acrylate polymers, polyvinyl acetals, or polyacrylate precursors to an acrylate polymer; and
(d) a solvent medium in an amount of less than or equal to 90 weight %, based on the total composition weight, which solvent medium is at least 50 weight % water;
provided that:
the weight ratio of the (b) particles to the (a) electrically-conductive material is at least 0.01:1 and up to and including 7:1, and
when the composition is coated and dried on an insulating substrate, a resulting dried composition exhibits a resistivity of less than 10,000 ohms-cm.
2. The composition of claim 1 , wherein the silver nanoparticles have a d50 of at least 1 nm and up to and including 230 nm and a d90 of less than or equal to 300 μm.
3. The composition of claim 1 , wherein when it is coated and dried on an insulating substrate, a resulting dried composition exhibits a resistivity of less than 500 ohm-cm.
4. The composition of claim 1 , wherein when it is coated and dried on an insulating substrate, a resulting dried composition exhibits a resistivity of less than 150 ohm-cm.
5. The composition of claim 1 , wherein the (a) electrically-conductive material is present in an amount of at least 60 weight % and up to and including 75 weight %, based on the total weight of the composition.
6. The composition of claim 1 , wherein the (b) particles are composed of one or more polymeric materials.
7. The composition of claim 1 , wherein the (b) particles comprise one or more elastomeric polymers.
8. The composition of claim 1 , wherein the (b) particles comprise an inorganic material.
9. The composition of claim 1 , wherein the (b) particles are present at greater than 0 volume % and up to and including 50 volume %, based on the total wet volume of the composition.
10. The composition of claim 1 , wherein the (d) solvent medium comprises at least 70 weight % water based on the total weight of the (d) solvent medium.
11. The composition of claim 1 , wherein the (d) solvent medium comprises at least 4 weight % and up to and including 40 weight % water based on the total weight of the (d) solvent medium.
12. The composition of claim 1 , wherein the (c) binder material comprises one or more preformed polyurethanes, each having a weight average molecular weight of at least 5,000.
13. The composition of claim 1 , wherein the (c) binder material is present in an amount of at least 0.05 weight % and up to and including 5 weight %, based on the total weight of the composition.
14. The composition of claim 1 , wherein the (c) binder material is present in an amount of at least 0.25 weight % and up to and including 3 weight %, based on the total weight of the composition.
15. The composition of claim 1 , wherein the (b) particles have a polydispersity coefficient that is less than or equal to 1.5.
16. The composition of claim 1 , wherein the (b) particles have a polydispersity coefficient that is less than or equal to 1.25.
17. A composition consisting essentially of:
(a) an electrically-conductive material consisting essentially of silver nanoparticles that have a d50 of at least 1 nm and up to and including 230 nm and a d90 of less than or equal to 300 μm;
(b) polymeric particles having a Young's modulus that is different from the Young's modulus of the (a) electrically-conductive material by at least 20%, and which (b) particles have a d50 of at least 1000 nm and up to and including 250 μm and a polydispersity coefficient of less than or equal to 1.5;
(c) a binder material that is non-electrically-conductive and comprises one or more polyurethanes, acrylate polymers, or polyvinyl acetals or polyacrylate precursors to an acrylate polymer, each having a weight average molecular weight of at least 5,000, and which binder material is present in an amount of at least 0.25 weight % and up to and including 3 weight %, based on the total weight of the composition;
provided that:
the weight ratio of the (b) particles to the (a) electrically-conductive material is at least 0.05:1 and up to and including 7:1, and
when the composition is coated and dried on an insulating substrate, a resulting dried composition exhibits a resistivity of less than 500 ohms-cm, and
the composition optionally further including (d) a solvent medium that can be present in an amount of at least 4 weight % and up to and including 40 weight %, based on the total composition weight, and which solvent medium is at least 90 weight % water, based on the total weight of the solvent medium.