(57) A molding roll (10) comprises a plurality of plate-like blades (11) having a same
shape and including neighboring first blades and second blades respectively, the blades
being laminated and center axes of the blades being positioned on the same line, the
blades having convex portion forming regions which are formed continuously every constant
pitch angle at their outer peripheries, each of the convex portion forming regions
constituting one of a roll ridge portion and a roll root portion, the roll ridge portion
being protruded outward to form one of the first convex portion and the fourth convex
portion, the roll root portion becoming depressed inward to form one of the second
convex portion and the third convex portion, the second blades being positioned to
be shifted by an integral multiple of the pitch angle relative to the first blades,
neighboring convex portion forming regions being aligned along the center axes when
the blades are laminated, laminated blades having first columns, which consist of
roll ridge portions constituting the first convex portions and roll root portions
constituting the third convex portions and are aligned along the center axes, and
second columns, which consist of roll root portions constituting the second convex
portions and ridge root portions constituting the fourth convex portions and are aligned
along the center axes, the first columns and the second columns being arranged alternatively
along a peripheral direction of the blades; and a spacer provided between the first
and second blades, the spacer creating a clearance to rise up the third convex portions
and the fourth convex portions.
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