T-Grain patents

[alanrockwood]

I am curious about T-Grain patents. T-Grain films have been marketed by Kodak for several decades now. This suggests to me that the key T-Grain patents would have expired for years by now. If so, then other manufacturers should be able to make films using T-Grain technologies if they want to.

Does anyone here know what the patent numbers and dates are for T-Grain technologies? I did a quickie search and didn't find the answers.

 

[Photo Engineer]

I don't have any t-grain patent numbers or the inventor's names OTOMH, but making t-grains is NOT a simple dump and stir Alan. Some of these preps take precision vAg control, special high speed mixing and can run hours in the making due to the number of operations. I'll see if I can locate some work for you to read.

(EDIT)
Just a quick search reveals this: 5576171, and it contains references that go back to the seminal work from earlier years. This patent expires in about 2 years or so, but the original work has expired. I hope that you like the simplicity of the emulsion using a variety of gelatins, lots of dumps and the use of a Lippmann emulsion.

PE

 

[snapguy]

big boys

The big boys -- multi-billion dollar corporations -- have a way of getting our greedy elected officials to extend things like patent dates and trademarks and such. Mickey Mouse should be in the public sector now but the Billion Buck Boys keep extending the trademark time frame -- something that the law was never intended to do. But money talks.

 

[AgX]

then other manufacturers should be able to make films using T-Grain technologies if they want to.

Alan, you are way behind time...

Nearly all manufacturers produced tabular chrystal films since many, many years.