Gelatin Size with sugar added...

[Dwayne Martin]

Hi Gang, has anyone heard of adding sugar to gelatin size for Gum printing? If so what does the sugar do exactly....
D

 

[Vaughn]

Sugar in gelatin allows the gelatin to retain a little moisture -- this keeps the gelatin pliable and less likely to crack if the paper is bent.

This is the role of sugar when making carbon prints (gelatin, sugar, and carbon). While I have not heard of using sugar in gelatin sizing, if one plans on applying a relatively thick coating of gelatin, it could be beneficial.

 

[Dwayne Martin]

Sugar in gelatin allows the gelatin to retain a little moisture -- this keeps the gelatin pliable and less likely to crack if the paper is bent.

This is the role of sugar when making carbon prints (gelatin, sugar, and carbon). While I have not heard of using sugar in gelatin sizing, if one plans on applying a relatively thick coating of gelatin, it could be beneficial.

Thanks!

 

[Don_ih]

J E L L O !

 

[nmp]

In addition to retaining moisture, sugar probably also acts as a plasticzer for dry gelatin - bringing down the so-called glass transition temperature and/or breaking the crystallinity of the pure gelatin with the same resulting increase in pliability as Vaughn describes.

 

[Andrew O'Neill]

I can't see any advantages to adding sugar to the size for gum, but what harm is there in trying it? Let us know how it goes!

 

[Dwayne Martin]

J E L L O !

At least until i mix in the Glyoxal....

 

[Dwayne Martin]

Sugar in gelatin allows the gelatin to retain a little moisture -- this keeps the gelatin pliable and less likely to crack if the paper is bent.

This is the role of sugar when making carbon prints (gelatin, sugar, and carbon). While I have not heard of using sugar in gelatin sizing, if one plans on applying a relatively thick coating of gelatin, it could be beneficial.

Turns out you guys are exactly right about the sugar making the gelatin more flexible. I read some gum printers are using 1 part sugar to 2 parts gelatin. I tried it once and really didn't notice any difference but I really didn't use very much.

 

[Vaughn]

I use it as 8% (60 grams per 750 ml of water...and 90 grams of gelatin).

 

[mshchem]

I've learned something new. Makes absolute sense. Is there any concern about this attracting microbes? Seems like sugar concentration is low enough, probably not a problem.

 

[Vaughn]

Depends on how long it takes to dry. We are talking petri dishes here! It can and has happened coating thick layers.
I have added thymol to prevent mold.