The base layer of YUPO® is biaxially stretched,
which mainly provides strength and stiffness, while
the paper-like surface layers that make up the top and
bottom of YUPO® are stretched horizontally only. Specifically,
the stretching process creates many microvoids that
scatter light, providing a high level of whiteness and
opacity. The manufacturing process also gives YUPO® a
paper-like quality that is good for both printing and
writing.
In addition, the numerous microvoids reduce YUPO®'s relative
density, which contributes to its light weight.
Although the base layer is biaxially aligned, because
the paper-like layers on the top and bottom are aligned
horizontally only, YUPO® has directionality.
Figure 2 shows the composition of YUPO®, while Figure
3 shows electron-microscope photographs and 3D images
of the surface and cross section of YUPO®, coated paper
and premium-grade paper. |
