摘要 |
The present invention relates to transparent microspheres (i.e., beads) that impart yellow color to retroreflected light. The microsphere preferably comprise titania plus alumina, zirconia, and/or silica and iron oxide, manganese oxide, or mixtures thereof. More particularly, the present invention relates to fused microspheres that impart yellow color to retroreflected light having both transparency and mechanical properties suitable, for example, for lens elements in retroreflective articles.
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