Too Much Au?

[wildbillbugman]

Hi to all,
I know that too moch Au can cause fogging. But I made an emulsion and took 70.0g to which I added 1.4g of 1% AuCl. The result was not fogging. The result was that the speed of the emulsion was greatly reduced. Does this make sense.?
Bill

 

[kb3lms]

Hi Bill,

That sounds like a lot of Au. Don't you need a thiocyanate along with the AuCl to make it work?

Most sensitizers turn into a de-sensitizer if you use too much.

-- Jason

Hi to all,
I know that too moch Au can cause fogging. But I made an emulsion and took 70.0g to which I added 1.4g of 1% AuCl. The result was not fogging. The result was that the speed of the emulsion was greatly reduced. Does this make sense.?
Bill

 

[Photo Engineer]

You used too much, and if the post is correct, you did not sue sulfur. You need either hypo or thiocyanate in there to do the sensitization properly. It is not called Sulfur + Gold sensitization for nothing.

PE