Re: Gum research

Richard Sullivan (richsul@roadrunner.com)
Thu, 03 Jul 1997 21:35:22 -0600

<x-rich>Nanson says:

> Dick,

>

>I've also had something similar in mind, looking at various water

>soluble synthetic polymers such as poly vinyl alcohol, and the modified

>celluloses in order to see how they compared with gum arabic. another

>thing that I had in mind was to look at the effect of using pyridium

>dichromate, and various light sensitising dyes on the printing speed of

>gum systems, as mentioned in Kosar's book 'Light Sensitive Systems'.

Pyridium dichromate. I can't find that in my handbook. My Mercke is at work. Know anything about this magic stuff. Sounds interesting.

>It seems to me that you will have to define the parameters pretty

>rigidly. Starting off with a standard formulation, on a standard

>substrate with a standard light source. Preferably using the same film

>thickness for each test, though how one measures this on paper I'm not

>sure. Perhaps one could use a well sized paper and coat with a meyer bar

>or a spinner, then measure the film weight. Then vary one parameter at a

>time!

No you're not teaching me to suck eggs, I appreciate your input. The problem as you note, is to be able to duplicate each coating and not to enter too many personal variables.

There was a nice thread a year ago on pigments and particle sizes and how to measure them. Very illuminating.

Welcome to the team. I'm going to be a little slow on the startup as the Ziatype article has us running in circles right now.

Dick

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