That's how this manufacturer defines technical papers as opposed to Graphic Arts Papers and Nonwoven Media, although I think there is some overlap.

http://www.mpm.com/products/technicalpapers.asp

TECHNICAL PAPERS

Abrasive Backing Papers
Art & Conservation Paper & Board
Durable Printing Stock
Ink Jet/Digital Imagind media
Wide Format Poster Stock
Medical Papers
Vacuum Filter Papers
Wallcovering Paper & Nonwovens
Tape Base

With its strong corporate commitment to product development, Monadnock has sought out technical/specialty and converting paper opportunities. The mill custom-designs papers that meet individual customer needs.

Monadnock produces technical products for a range of uses including high internal bond abrasive backing, tape system components, high fold and elongation durable book covering, controlled porosity sterilizable medical packaging, high porosity vacuum filter media, and latex-treated, aqueous coated strippable wallcoverings. In addition to custom fiber furnishes, ranging from woodpulp to synthetics, many technical grades are treated with special additives, including a wide variety of latices used for saturating and coating. Monadnock's coating operation is capable of imparting both printable and specialty functional coatings, such as adhesive and surface barrier treatments, all aqueous dispersions of .25 - 30 pounds per ream (24x36/500) on each side of the web.

Another manyfacturer has these for "technical and industrial papers":
Base paper for Lamination
for PE-extrusion and for Film protection
http://www.coldenhove.com/index2.html