how to size paper ?

Discussion in 'Alternative Processes' started by hemphrey, Apr 6, 2009.

  1. hemphrey

    hemphrey Member

    Mar 22, 2009
    Plastic Cameras
    Hello everyone,

    I would like to know how can i cover Guar gum on the surface of my normal printable paper

    Is there any simple method to do that ? ( I don't have sophisiticated tools with me :S but i ask this because i heard that gum protects the paper )

    Thank you guys ! :smile:
  2. nawagi

    nawagi Member

    Mar 29, 2006
    Large Format
    Use gelatin (Knox's or photo grade, 200 -250 bloom). Put 30 grams in 500 ml distilled water. Allow to swell for 20 minutes. Heat over a double boiler until gelatin has melted. Apply by foam brush, coating blade, or immersion. hang to dry. If double coating, you must harden the intiial coating with formalin or gyloxol.

  3. Katharine Thayer

    Katharine Thayer Member

    Jan 22, 2007
    4x5 Format
    Hemphrey, your choice of sizing material intrigues me. Why are you thinking of guar gum? I've never heard of anyone using it for a size, but that doesn't mean I don't think it would work, it just means you may need to do the legwork yourself as far as experimenting with it. And what process do you want to print on the sized paper? For gum printing, gum arabic can work as a size if it's crosslinked so so as not to be soluble in water. Some people mix it with dichromate and expose it to light to crosslink it; that's more trouble than I want to go to and I crosslink it by mixing it with glyoxal when I've used gum arabic as a size. Not being familiar with guar gum I have no idea how similar it is to gum arabic in structure, solubility, or how well it crosslinks as a dichromated colloid or with a crosslinking agent like glyoxal, so it's impossible to tell you how to use it as a size, sorry.