If the weight you require is similar to file folder material, you should
test if your printer will allow that material through and be able to
fuse the toner well enough.
There are several issues in selecting a media for a laser printer to
consider:
1) will it successfully go through the printer
This is determined by the thickness of the material, how slick a surface
the material has (if it will slip during paper transport and printing)
and finally how flexible the medium is. Some media are relatively
flexible in one direction but not when turned 90 degrees. Paper media
has a grain, and so one side tends to have more flex than the other.
Try to use the direction that allows for most flexibility in the
direction across the page, rather than top to bottom. You need to
figure out how much flex you need to get proper paper transport and to
have proper contact on the drum and the fuser.
2) will the toner stick
There are several factors that will determine if the toner will stick
during the transfer from the drum to the medium.
The medium needs to accept the correct static charge so the toner will
transfer and stick. The surface needs to hold the toner in place
without it slipping and smudging, while contacting the printing drum.
3) The medium needs to allow proper fusing of the toner
The last step of the printing process on laser printers is the medium is
heated to melt the toner on to the surface.
If the medium is too heat sensitive, it can melt, singe, change
dimension, dry and crack, etc.
If it is too thick, it can absorb too much of the heat and the toner may
not melt fully or adhere to the medium.
If the medium has a surface that won't hold toner, due to some type of
treatment, the toner may crack or peel off.
That's why, as long as it won't do damage to the printer (like melt
during fusing) it is best to test a medium before committing to it.
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Having said all this, most stationary stores carry index or card stock
designed for laser printing. It is not quite as thick as most file
folder paper stock, but it works with most black and white laser printers.
Art