Copper powder
A copper powder that is excellent in weatherability and adapted for use in conductive paste is provided that contains 10-20,000 ppm, preferably 100-2,000 ppm, of Sn. The copper powder is particularly preferably one having an average particle diameter DM of 0.1-2 μm and, further, one wherein the particle diameter of at least 80% of all particles is in the range of 0.5 D M -1.5 D M . This copper powder can be produced, for example, by precipitating Cu metal by reduction of Cu ions in the presence of Sn ions.
1 . A copper powder containing 10-20,000 ppm of Sn.
2 . A copper powder containing 100-2,000 ppm of Sn.
3 . A copper powder according to claim 1 , whose average particle diameter DM is 0.1-2 μm.
4 . A copper powder according to claim 1 , whose average particle diameter DM is 0.1-2 μm and wherein the particle diameter of at least 80% of all particles is in the range of 0.5 DM-1.5 DM.
5 . A copper powder according to claim 1 , obtained by precipitating copper metal by reduction of Cu ions in the presence of Sn ions.
6 . A copper powder according to claim 1 , obtained by precipitating copper metal by reduction of cuprous oxide containing 10-1,000 ppm of Sn.
7 . A copper powder suitable for use as filler in a conductive paste, containing 10-20,000 ppm of Sn, whose average particle diameter DM is 0.1-2 μm and the particle diameter of at least 80% of all particles is in the range of 0.5 DM-1.5 DM.
8 . A copper powder according to claim 2 , whose average particle diameter DM is 0.1-2 μm.
9 . A copper powder according to claim 2 , whose average particle diameter DM is 0.1-2 μm and wherein the particle diameter of at least 80% of all particles is in the range of 0.5 DM-1.5 DM.
10 . A copper powder according to claim 3 , whose average particle diameter DM is 0.1-2 μm and wherein the particle diameter of at least 80% of all particles is in the range of 0.5 DM-1.5 DM.
11 . A copper powder according to claim 2 , obtained by precipitating copper metal by reduction of Cu ions in the presence of Sn ions.
12 . A copper powder according to claim 3 , obtained by precipitating copper metal by reduction of Cu ions in the presence of Sn ions.
13 . A copper powder according to claim 4 , obtained by precipitating copper metal by reduction of Cu ions in the presence of Sn ions.
14 . A copper powder according to claim 2 , obtained by precipitating copper metal by reduction of cuprous oxide containing 10-1,000 ppm of Sn.
15 . A copper powder according to claim 3 , obtained by precipitating copper metal by reduction of cuprous oxide containing 10-1,000 ppm of Sn.
16 . A copper powder according to claim 4 , obtained by precipitating copper metal by reduction of cuprous oxide containing 10-1,000 ppm of Sn.