PURPOSE: To provide good fixing properties and good bleeding, in recording paper having the exposed parts of pulp fibers and the parts covered with particles of pulp fibers coexisting on the surface thereof, by setting the absorption coefficient of raw paper, whose contact time in a Bristol test using ink of which the surface tension at specific temp. is a specific value is the specific value or less, used in the production of the recording paper to the specific value or more.
CONSTITUTION: Recording paper is based on chemical pulp, a size agent and a filler and contains other papermaking auxiliary agents if necessary and is produced by applying an aq. coating soln. containing pigment, a resin and other additives to recording raw paper produced by a usual papermaking method and dying the coated raw paper and characterized by that the exposed parts of pulp fibers and the parts covered with particles of pulp fibers coexist on the surface thereof. The absorption coefficient of the recording raw paper of the recording paper for a contact time of 4 msec or less must be 10 [ml/(m2.msec1/2)] or more like raw paper C. The absorption coefficient is the inclination of a graph formed from the transfer amt. of a liquid per a unit area with respect to the 1/2 flux of the contact time calculated in a Bristol test using ink of which the surface tension at 25°C is 45-50 dyne/cm.
SUZUKI EIICHI
SAKAKI MAMORU
KATAYAMA MASATO
