Kodachrome patent

[Aurum]

As mentioned in the Kodachrome thread, I've attached a PDF of the original Richard Bent / Rowland Mowrey patent which I sourced as a PDF off espacenet. You can get to this service via your local european patent office (I went via Dead Link Removed )
This version is in English, Espacenet will also allow you to download versions in different languages.
These are:
DE2159903 (B2) German
US3658525 (A) Original American patent
CH536502 (A) Swiss Patent
FR2117338 (A5) French Patent
JP51021582 (B) Japanese Patent

Otherwise go to the Dead Link Removed and download it from there

 

[Ian Grant]

So are you going to try and make Kodachrome on the Landrover production line ? Only a Brummie logic could think they are compatible

Ian

 

[wogster]

As mentioned in the Kodachrome thread, I've attached a PDF of the original Richard Bent / Rowland Mowrey patent which I sourced as a PDF off espacenet. You can get to this service via your local european patent office (I went via Dead Link Removed )
This version is in English, Espacenet will also allow you to download versions in different languages.
These are:
DE2159903 (B2) German
US3658525 (A) Original American patent
CH536502 (A) Swiss Patent
FR2117338 (A5) French Patent
JP51021582 (B) Japanese Patent

Otherwise go to the Dead Link Removed and download it from there

Thanks, that's easier then the version I was looking at, you can tell how old it is, it was filed on paper, and scanned at some point, by someone who was not that good at scanning, some of the pages are crooked.

 

[Photo Engineer]

Note that the patent gives a more vague reference to the couplers, but data on the mixing of the solutions. The actual couplers are listed here in the PDF along with the developers needed (CD-3 and CD-6)

(there was a url link here which no longer exists)

There will be differences between the patent and the actual current process as it was still being tweaked at the time the patent was filed. It should be close enough to give quite good results though.

PE

 

[Scott_Sheppard]

Note that the patent gives a more vague reference to...

PE:

You NEVER Said you where on the current Kodachrome Patent !!

Now I MUST get your Lunch and DINNER next time we hang out !!!

WOW.... !!!

Thanks

Scott

 

[Photo Engineer]

You never asked!

Seriously, it isn't that important to me but does explain my interest.

PE

 

[Heinz_Anderle]

As the modern Kodachromes have set the standards in 35 mm color photography for high-quality offset printing from the mid 1970s onwards, it is a great honor to meet one of its fathers here.

It is still a delight to look at such 25 - 30 year old photo books. And, even as I have started photography at the time when the green boxes showed up, the Kodachromes defined my perception of color rendition, not the jelly bean candy of the 1990s.

The monography on the cultural history of modern Kodachrome has yet to be written.

 

[Photo Engineer]

Well, please minimize my effort. My work was on the color developing agent in the yellow developer, CD-6, and in color paper. I collected the other work into a comprehensive whole and so doing learned a lot about Kodachrome including how it could be lab (hand) processed. My work with Bent and others is a compilation of the work of many but since Dick and I had the "ah hah!" moment here, they gave us our names on the title page.

BTW, Dick's nephew is an APUG member and Dick sadly passed away late last year. About 15 of us former EK co-workers were at a recent memorial service. It was a great loss to the field of color developer synthesis and testing. Dick knew just about everything in the Kodak archives on these subjects.

PE

 

[Aurum]

You never asked!

Seriously, it isn't that important to me but does explain my interest.

PE

Ron, if it gets you a free lunch........

 

[Photo Engineer]

Ron, if it gets you a free lunch........

It says lunch and dinner! :munch: :munch:

PE

 

[MattKing]

So Ron:

Should we call you Rowland?

I've wondered if it was you since I first saw the reference to the patent.

Matt

 

[Photo Engineer]

Matt, Ron is fine.

PE

 

[Jamie S]

Matt, Ron is fine.

PE

Seems to me that with your wealth of knowledge and willingness to share, we should call you Professor PE
I know I've managed to learn a couple of things from your posts.

 

[accozzaglia]

Usability assistance.

Hi all —

The attached PDF here is the same as the previous document, but is now text-searchable.

-A

 

[Neanderman]

So, inquiring minds are curious. Why was CD-6 only used for the yellow developer? Where the other two color developers substantially changed from what was used in K-12?

Ed

 

[Photo Engineer]

Well, the patent shows CD-4 being used for Cyan and Magenta, but I was told it was CD-3 in K-14. Now, I am confused as well. CD-3 and CD-6 generally yield dyes with better dye stability and better hue for viewing with the human eye. That is why CD-6 was chosen and why I believe that CD-3 is used in the other two developers.

CD-6 was planned for use in the generation of color paper after Ektacolor 70 paper (Ektaprint 3 process in 1969) and in Ektachrome E-6. However, Kodak was sued by Berkey, Pavelle and GAF for coming out with the Ektaprint 3 process and plans for the upgrade to CD-6 were cancelled.

If plans had continued, there is a good chance that RA4 and E6 would be run with CD-6 with even better dye hue and even better image stabilty. You can thank those that sued Kodak, making management nervous about changing processes for this.

PE

 

[accozzaglia]

However, Kodak was sued by Berkey, Pavelle and GAF for coming out with the Ektaprint 3 process and plans for the upgrade to CD-6 were cancelled.

If plans had continued, there is a good chance that RA4 and E6 would be run with CD-6 with even better dye hue and even better image stabilty. You can thank those that sued Kodak, making management nervous about changing processes for this.

PE

The question I'm wondering is why did they sue Kodak?

 

[CuS]

The question I'm wondering is why did they sue Kodak?

patent infringement. being the big dog, kodak attracted all of the juicy infringement suits.

 

[John Shriver]

No, the lawsuits by Berkey et. al. were brought on anti-trust grounds. Remember that Kodachrome isn't sold with processing included in the US due to anti-trust suits, there was a consent decree in 1955. It was claimed that Kodak was trying to monopolize film processing by bundling processing with Kodachrome.

There were anti-trust lawsuits about the C-41 process, by large labs who were blindsided by the change from C-22 to C-41. Due to the higher temperatures and shorter times, the labs had to buy new equipment. Again, it was argued that Kodak was changing the developing process just to torture independent processing labs, forcing them to make large capital purchases. Kodak was really just trying to make better film, and the matching processing.

Remember that at the time, Kodak really was the largest processor of color film in the US. (They were just a bit player in B&W.)

Remember also that Kodak did lose a patent lawsuit with Polaroid. There's good arguments that the case was lost due to the judge ignoring the technical arguments. Basically, the judge felt "Polaroid invented instant photography, so ipso facto Kodak is violating their patents, even if they have not violated any claims." Patent lawsuits are often handled abysmally by the courts, it's really a complete gamble to participate in one. (This is one of the reasons US Patent law is such a mess, and Patent Trolls are such a problem.)

(I don't know if Kodak had lost the Polaroid patent case when they decided to punt on further uses of CD-6.)

So, at any rate, Kodak was intimidated by the anti-trust lawsuits, probably particularly the C-41 one, and chickened out on using CD-6 in RA-4 and E-6. A shame.

 

[Photo Engineer]

Kodak punted before the Polaroid lawsuit.

And, incidentally, the GAF paper went through Kodak's Ektaprint 3 process as well as Kodak paper, but this was ignored by the court. It was judged on the basis of change per se not on any actual damage caused AFAIK.

PE

 

[Heinz_Anderle]

According to the material safety data sheets for the K-14M (K-Lab) developers, the color developer is CD-3 for the magenta developer and CD-4 for the cyan developer.

http://www.siri.org/msds/gn.cgi?query=k-lab

 

[AgX]

Currently Kodak and Agfa are sueing each other in several cases on claimed patent infringement.
A court decision on the whole complex has been made and Agfa won but Kodak is appealing.

(Kodak stated that Aga was violating 7 of their patents. It is about X-ray films, more precise on a antihalation techniqe for dubblesided films with intensifyer screens [anti-crossover] by means of employing tabular crystals.)

 

[accozzaglia]

No, the lawsuits by Berkey et. al. were brought on anti-trust grounds. Remember that Kodachrome isn't sold with processing included in the US due to anti-trust suits, there was a consent decree in 1955. It was claimed that Kodak was trying to monopolize film processing by bundling processing with Kodachrome.

There were anti-trust lawsuits about the C-41 process, by large labs who were blindsided by the change from C-22 to C-41. Due to the higher temperatures and shorter times, the labs had to buy new equipment. Again, it was argued that Kodak was changing the developing process just to torture independent processing labs, forcing them to make large capital purchases. Kodak was really just trying to make better film, and the matching processing.

Remember that at the time, Kodak really was the largest processor of color film in the US. (They were just a bit player in B&W.)

Remember also that Kodak did lose a patent lawsuit with Polaroid. There's good arguments that the case was lost due to the judge ignoring the technical arguments. Basically, the judge felt "Polaroid invented instant photography, so ipso facto Kodak is violating their patents, even if they have not violated any claims." Patent lawsuits are often handled abysmally by the courts, it's really a complete gamble to participate in one. (This is one of the reasons US Patent law is such a mess, and Patent Trolls are such a problem.)

(I don't know if Kodak had lost the Polaroid patent case when they decided to punt on further uses of CD-6.)

So, at any rate, Kodak was intimidated by the anti-trust lawsuits, probably particularly the C-41 one, and chickened out on using CD-6 in RA-4 and E-6. A shame.

Thank you. This answer makes sense and helps me understand what was going on that precipitated litigious action.

 

[Q.G.]

Eastman/Kodak has been involved in patent disputes continuously since at latest 1889 (maybe even earlier), and not just because of other people's/company's envy of their succes.
Eastman knew a trick or two himself when not wanting to reinvent the wheel (and/or pay for it) was concerned. I'm sure the company carried on in his spirit for a long while.

What should also not be forgotten about patents is that they very rarely contain correct detailed descriptions of how things are done.
They are not meant to allow other companies to have a look in, but quite the opposite: to shut other companies out. So (apart from describing in length why the claims made are not already "prior art") they more often than not paint the broadest possible picture of the genius of a certain idea (mentioning every imaginable way an idea could be applied), while deliberately providing incorrect details.
Or in other words: patents are part of business tactics. Not scientific or historic documents.

Sometimes it doesn't need law suits to stop something dead in its tracks. Disc film, for instance, though making a great start, was effectively 'killed' because photofinishers did not like to have to invest in more equipment.
It may even be suggested that the only practical purpose disc film served was to force photofinishers to invest in new processing machines.
APS also held no advantage for photographers, so could also be construed as an attempt to 'help' the photofinishing apparatus market along a bit.

 

[Photo Engineer]

According to the material safety data sheets for the K-14M (K-Lab) developers, the color developer is CD-3 for the magenta developer and CD-4 for the cyan developer.

http://www.siri.org/msds/gn.cgi?query=k-lab

I would be careful about this page or the MSDS data.

The first 6 yellow developers listed used CD-4 and the 7th used CD-6 so something is wrong with the list somehow.

PE