Size
noun
1. any of various gelatinous or glutinous preparations made from glue, starch, etc., used for filling the pores of cloth, paper, etc., or as an adhesive ground for gold leaf on books.
verb (used with object), sized, sizing.
2. to coat or treat with size.
A couple of weeks ago, as part of a group, I had a look at adding size to my handmade paper.
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An aside:
In new fabric, especially patchwork/quilting cotton, you can feel the stiffness of the fabric, the crisp, smooth, un-creased surface, all achieved by adding size to the mix. Have you ever wondered why new clothing, fitting so perfectly and hanging just right then goes floppy, out of shape and often shrinks after washing? That’s because, when new, they are impregnated with size but once washed that has gone down the drain (along with your money if your garments no longer fit!) and you are left with the ‘real’ fabric, I suppose you could say.
So what’s the point of size in paper? All commercially made paper (hesitate… hesitate… qualify further), and by this I am referring to copy paper, cartridge, Stonehenge, BFK Reeves, and the like, have some size in them. It helps paper:
- repel damp (otherwise a nightmare in humid conditions). Note: in large stationery stores it is possible to buy large boxes of A4 copy paper, the equivalent of 5 reams (2500 sheets) without much packaging. It’s cheap. Why? Because it has minimal size and will absorb any air moisture if not used within a short time – and I mean only a few weeks!!
- stay crisp (keeps sheets sturdy and separate for going through a copier or scanner).
- reduce the degree of liquid absorption enabling other media to sit atop the surface (printing inks, glue, pencils and so on).
- have a smooth surface by acting as a filler or surface glaze.
- increase surface bond strength, decreasing any fuzziness or furriness on the surface.
Some papers are either unsized or what is termed weak sized and into these two categories fall blotting paper, newsprint, water-colour paper and others that you will find do not repel water or moisture. However, as a printmaker, I’m interested in sized paper to obtain sharp print outcomes.
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We looked at the two methods of sizing; internal and external.
Internal
Size is added to the vat as the pulp is being formed into sheets. So it is an integral part of the finished paper.
I tried both a commercial starch and some wallpaper paste, in separate vats of course!
There was a noticeable change in water viscosity and I obtained good paper from both.
External
Size is brushed onto existing paper and allowed to dry, thereby coating the surface and allowing some absorption.
I tried gelatine ( used fairly warm otherwise it sets), rabbit skin glue, hercon and konyaku (commercial sizes).
The Results:
Image by Shawn Knoll, DeviantArt
Well, hmmmmm…… not sure that I achieved the correct results.
As I understand it, if a drop of water is applied to the surface it should sit there before being slowly absorbed. That isn’t happening on most of my sheets.
Maybe it only becomes apparent when you print on it and I’m expecting too much – but I don’t think so.
Below you can see the finished sheets, using internal sizing:
Only the powdered starch with metholated spirits mixed in (to help it dissolve) inhibits the water from passing straight through the paper.
Using external sizing:
Only the gelatine size has held the water on the surface. All other samples reacted like blotting paper.
What a fascinating thing. I need to talk to others who know more than I, to check my results. Another interesting point is how crinkled the paper became when dry, even though they were rolled onto proper drying boards. As they dried they unstuck from the boards and curled – some of the sheets remind me of those puffed prawn crackers you get when ordering Chinese take-away!
Click here to see more imagery of the day.
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