General paper property that takes into account two measures of a paper's ability to withstand being torn. Internal tearing resistance refers to the work required to tear a paper sample through a specified distance once the tear has been started. Edge tearing resistance refers to the work required to tear a paper sample by starting the tear at the edges of the sheet. Lighter papers are more susceptible to edge tears than to internal tears, so the latter measurement is frequently the more useful one. Tearing resistance is an important property in many end-use applications, from cover, wrapping, bristol, and bond papers to map and envelope papers.
As with most paper properties, tearing resistance is a function of the degree of fiber refining; greater interfiber bonding enhances tearing resistance, but excessive refining tends to shorten the fibers, which works to decrease the tearing resistance. The addition of fillers decreases tearing resistance. The procedures that increase tearing resistance sometimes diminish other desirable properties. (See Paper and Papermaking: Paper Properties.) Also known as tearing strength or simply tear.