Spray Starch - Sizing agent - Gum Bichromate

[Mac064]

Hi all,

I was looking through old threads and could not find one specifically that dealt with spray starch as a sizing agent in gum bichromate printing. I was wondering if anyone had any good advice in relation to using spray starch for sizing rather than gelatin in the gum bichromate process?

I normally size paper in a gelatin solution using the immersion method and draw the paper over the edge of the tray prior to hanging to dry. I kind of prefer this to coating using a brush on the taped down paper. I do, however find that this is a bit time consuming (not much I know and you can do batches of paper) and I also find that I have to press the paper flat after drying as it does have a tendency to warp during drying.

Using spray starch would certainly be quicker and more efficient and maybe would cut out or lessen any warping but are there drawbacks? Maybe starch (spray especially) would not be as effective a sizing agent? Has anyone used spray starch in gum bichromate printing (or other processes for that matter).

Sorry for the somewhat basic question. I may go ahead and try it anyway but any thoughts or advice would be very welcomed.

Best.

 

[fschifano]

I'm just guessing here, but I'd think that starch is too water soluble for this application. If you've used it for its intended purpose on a shirt, you'd know that once laundered, it's gone.