| CPC B43K 1/082 (2013.01) [C04B 35/48 (2013.01); C04B 35/62675 (2013.01); C04B 35/64 (2013.01); C04B 2235/3208 (2013.01); C04B 2235/3217 (2013.01); C04B 2235/3225 (2013.01); C04B 2235/3229 (2013.01); C04B 2235/3244 (2013.01); C04B 2235/604 (2013.01); C04B 2235/612 (2013.01); C04B 2235/6567 (2013.01); C04B 2235/77 (2013.01); C04B 2235/963 (2013.01)] | 20 Claims |
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1. A writing instrument comprising:
a ceramic writing ball,
wherein the ceramic writing ball comprises relative to the total weight of the ceramic writing ball:
about 1.0 wt.-% to about 14.6 wt.-% of Y2O3, HfO, MgO, CaO and/or Ce2O3,
about 0.15 wt.-% to about 3.0 wt.-% Al2O3, and
ZrO2 as balance.
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