Curling paper

[Geoff Hart <geoff-h -at- MTL -dot- FERIC -dot- CA>]

     As the forest industry mouthpiece (see message re. paper and trees for
     details!), I should add my two cents to this one too:

     1. Yes, most of the problem with curling paper is due to dampness.
     Paper is highly hygroscopic (it absorbs moisture), and it expands and
     contracts (respectively) as it absorbs and loses moisture. To reduce
     or completely eliminate curling, store it somewhere dry. If this is
     impossible, putting the paper in a microwave oven for a few seconds
     (test your own paper to see how many) drives off the moisture and
     reduces this problem. Don't try this with your cat.

     2. Even if your paper is relatively dry to begin with, passing it
     through the laser printer a second time will often cause some degree
     of curling. The reason is that the first exposure to the heating
     element drives off some water, and the second pass by the heater
     drives off still more water, which causes dimensional changes (i.e.,
     curling). This is especially true with common copier paper, especially
     the recycled variety, which isn't designed for two-sided copying. (You
     can get higher-grade copy paper that works just fine this way,
     provided it's dry.) If you use a duplexing printer, moisture control
     is very important and you probably still won't get the same quality as
     with single-sided printing.

     Incidentally, paper is not as dimensionally stable as film, which is
     why 1200 dpi output looks significantly better from a typesetter than
     from a laser printer.

     --Geoff Hart  #8^{)}