[alt-photo] Re: casein+ alt to dichromate

[Christina Anderson]

Hmmm, Peter, my copy of the British patent specifies methyl; however, it is patent 20,740. I actually have about five copies of Gateau patents. The only one that says metallic is this Google one. I wonder if Google's scanner does automatic spelling correction :)
Chris

Christina Z. Anderson
christinaZanderson.com

On Jun 22, 2012, at 10:28 PM, Peter Friedrichsen wrote:

> 
> That patent has a translation error. The US and Great Britain patents specify  metallic violet (line 52) as a visible light sensitizer dye, but the french patent specifies "violet de méthyle" which is methyl violet, a well known dye. Metallic violet doesn't exist, or perhaps only in the subconscious ; )
> 
> I came across this error when exploring dyes for use as visible light sensitizers in gum and casein emulsions.
> 
> Peter Friedrichsen
> 
> At 04:31 PM 22/06/2012, you wrote:
> 
>> On 20 jun. 2012, at 19:47, Peter Friedrichsen wrote:
>> 
>> > Looks like you got it all to work. Congrats on that.
>> 
>> 
>> Chris (thanks again!) pointed me off-list to this patent of J T Gateau,  she spotted somewhere:
>> 
>> http://www.google.com/patents/US905306?printsec=abstract#v=onepage&q&f=false
>> 
>> Ferric caseïn avant la lettre: the original patent was filed in 1907!
>> 
>> -k
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