Method of producing a surface finish on an electrically conductive substrate and electric conductor with the surface finish thereon
A method for producing a surface finish on an electrically conductive substrate includes transferring an ink having a plurality of electrically conductive particles onto an area of a predetermined form and/or size on a surface of the electrically conductive substrate by gravure and/or flexo printing. The ink is heated to a temperature that is higher than a melting point of the electrically conductive particles to create a melt. The melt solidifies into the surface finish on the electrically conductive substrate.
1 . An electric conductor, comprising:
an electrically conductive substrate having a surface with an area of predetermined size and/or form on which a surface finish is applied, the surface finish is produced by:
transferring an ink having a plurality of electrically conductive particles onto the area by gravure and/or flexo printing; and
heating the ink to a temperature that is higher than a melting point of the electrically conductive particles to create a melt, which solidifies into the surface finish on the electrically conductive substrate, a layered structure is formed in the area that has an intermetallic phase and a layer of solid electrically conductive particles.
2 . The electric conductor of claim 1 , wherein the layer of solid electrically conductive particles forms a top layer of the surface finish.
3 . The electric conductor of claim 1 , wherein a plurality of edges of the surface finish have a lateral resolution of less than 1 mm.
4 . The electric conductor of claim 1 , wherein the surface finish has a predetermined variation of thickness within the area.
5 . The electric conductor of claim 1 , wherein the surface finish has a thickness from about 0.75 to about 5 micrometers.
6 . The electric conductor of claim 1 , wherein the surface finish has an organic material from about 0.01 to about 0.5 wt % organic material.
7 . The electric conductor of claim 1 , wherein the surface finish has a particulate structure on the surface.
8 . An electric conductor, comprising:
an electrically conductive substrate having a surface with an area of predetermined size and/or form on which a surface finish is applied, a plurality of edges of the surface finish have a lateral resolution of less than 1 mm, the surface finish is produced by:
transferring an ink having a plurality of electrically conductive particles onto the area by gravure and/or flexo printing; and
heating the ink to a temperature that is higher than a melting point of the electrically conductive particles to create a melt, which solidifies into the surface finish on the electrically conductive substrate.
9 . An electric conductor, comprising:
an electrically conductive substrate having a surface with an area of predetermined size and/or form on which a surface finish is applied, the surface finish has an organic material from about 0.01 to about 0.5 wt % organic material, the surface finish is produced by:
transferring an ink having a plurality of electrically conductive particles onto the area by gravure and/or flexo printing; and
heating the ink to a temperature that is higher than a melting point of the electrically conductive particles to create a melt, which solidifies into the surface finish on the electrically conductive substrate.
10 . An electric conductor, comprising:
an electrically conductive substrate having a surface with an area of predetermined size and/or form on which a surface finish is applied, the surface finish has a particulate structure on the surface, the surface finish is produced by:
transferring an ink having a plurality of electrically conductive particles onto the area by gravure and/or flexo printing; and
heating the ink to a temperature that is higher than a melting point of the electrically conductive particles to create a melt, which solidifies into the surface finish on the electrically conductive substrate.
11 . A method for producing a surface finish on an electrically conductive substrate, comprising:
transferring an ink having a plurality of electrically conductive particles onto an area of a predetermined form and/or size on a surface of the electrically conductive substrate by gravure and/or flexo printing, the ink is a first ink having a first set of electrically conductive particles and is transferred to a first area of predetermined form and/or size by gravure and/or flexo printing, and a second ink having a second set of electrically conductive particles is transferred to a second area of predetermined form and/or size, a material of the first set of electrically conductive particles is different than a material of the second set of electrically conductive particles; and
heating the first ink and the second ink to a temperature that is higher than a melting point of the first set and the second set of electrically conductive particles to create a melt, which solidifies into the surface finish on the electrically conductive substrate.
12 . The method of claim 11 , wherein the first ink and the second ink are heated by induction heating the electrically conductive substrate.
13 . The method of claim 11 , wherein the first set of electrically conductive particles comprise tin.
14 . The method of claim 11 , wherein the first ink and the second ink are melted in subsequent steps.
15 . The method of claim 14 , wherein the first ink is melted via induction heating.
16 . The method of claim 15 , wherein the second ink is melted via electron beam melting.
17 . The method of claim 11 , wherein the first set of electrically conductive particles has an average particle size of about 2 μm to about 5 μm.
18 . The method of claim 11 , wherein the first ink has a dynamic viscosity below 10 Pa s, measured at 10 s −1 at 25° C.
19 . The method of claim 11 , wherein the first set of electrically conductive particles has an oxygen content of less than 1 wt %.