New HC-110 Formula

[relistan]

Here is the year-old concentrate I made. View attachment 335718

Sorry I think I missed what you were trying to convey there with regard to my question about catechol. Good thread though.

 

[alanrockwood]

I have a hypothesis about why catechol might be found in HC-110.

The MSDS for HC-110 lists hydroquinone as an ingredient. Catechol is an isomer of hydroquinone, and is formed as a side product in some processes for making hydroquinone, such as the catalytic hydroxylation of phenol with hydrogen peroxide to make hydroquinone. The catechol might simply be carried along as a byproduct of hydroquinone synthesis. It's probably not all that useful or economical to purify the hydroquinone to rid it of catechol, particularly if the catechol isn't hurting the function of HC-110, and might even be helpful to the function of that developer.

 

[bnxvs]

I apologize for not being able to answer right away - a little life troubles.
Actually, my assumption about why the patent composition of HC-110 contained catechol is based on a once read somewhere (of cource, I don't remember where) material about the comparison of the oxidation rate of hydroquinone and the Catechol. The Catechol, according to that information, oxidized much faster, both individually and in solution together HQ & Catehol.
I can only assume that Catechol was introduced into HC-110 as a kind of «sacrificial lamb» ))).

 

[doctorpepe]

It’s too bad Photo Engineer passed away. He would probably know exactly why Kodak added catechol to hc110!

 

[Juan Valdenebro]

Now it's been 4-5 years since the new formula, and if I'm not wrong, it keeps well too.
Any considerable difference?
My 1980's syrup bottle is nearly full, and dil. B is my favorite for overcast with HP5+... Is the new formula(s) as good for expansion with HP5+?

 

[abddba]

可惜摄影工程师去世了。他可能会确切地知道柯达为什么在hc110中添加儿茶酚！

或许是因为儿茶素具有使显影区域的明胶硬化的作用，可以提高分辨率。

 

[cmacd123]

google tells me the previous post says :
It's a pity that the photography engineer passed away. He might know exactly why Kodak adds catechol to hc110! Click to expand... Perhaps this is because catechins have the effect of hardening gelatin in the developing area, thereby improving resolution.

gee, I did not think we had to use that amount of technology just to follow the action....

 

[Tim Stapp]

I believe that the reference was to Ron Mowry, who's name here was "Photo Engineer." He was a legend. He was a retired Kodak Chemical Engineer that had hands on (in, as in designed) many of Kodak's film and chemistries. Not to mention a couple of Photographer's Formularie's patentend products. Do a search on this site to see his many contributions.

Regardless, given the state of Kodak chemistry and Sino Promise, anything Kodak chemistry related is in the gravel in my humble opinion. RIP Ron Mowry and Kodak chemisry.

 

[MattKing]

FWIW, he was actually Rowland (Ron) Mowrey - the Rowland Mowrey whose name is found on many Kodak patents.
And he is greatly missed.

 

[cmacd123]

FWIW, he was actually Rowland (Ron) Mowrey - the Rowland Mowrey whose name is found on many Kodak patents.
And he is greatly missed.

absolutely. Photo Inventor would have been a more accurate title.

 

[Tim Stapp]

FWIW, he was actually Rowland (Ron) Mowrey - the Rowland Mowrey whose name is found on many Kodak patents.
And he is greatly missed.

Yes, he is greatly missed! I apologize for the delayed response. I was working on a volunteer project at a remote Lake Michigan Lighthouse. See here: https://www.facebook.com/whiteshoallight. That's me at the back of the boat. The restored retired Coast Guard CG 30410 is itself registered as an historical landmark.