Pigments based on Er2O3-Al2O3: Preparation and colouring performance in zirconia ceramics

Microstructure, physical and mechanical properties of dental polychromic multilayer zirconia of uniform composition

“…For instance, the absence of the weaker monoclinic phase is extremely important, because the presence of this phase would lead to surface degradation and feature poor resistance to microcrack propagation [1]. There was also no evidence of the formation of other crystalline phases related to pigments (e.g., Er 3 Al 5 O 12 ) [15]. These results match well with the elemental analysis results conducted at the surface of specimens from the three investigated zirconia groups where only Zr, O, and Y elements were detected.…”

“…To sum up, the amount of yttria defines the translucency of zirconia ceramics, whereas the pigments (added in smaller amounts than yttria, i.e., ∼1%) define the color of zirconia, where their concentration defines the color intensity. Several types of pigments are usually introduced in PMZs of uniform composition, such as CeO 2 , Er 2 O 3 , ErAlO 3 , Pr 6 O 11 , Fe 2 O 3 , and MnO 2 [13][14][15]. However, they must be carefully added in order to obtain the correct degree of lightness, redness/greenness, and yellowness/blueness, with the aid of CIELab, HSB/HSV, or other systems [16].…”

Fabrication and properties of pink 3 mol% yttria‐stabilized zirconia ceramics with high toughness

“…In 2020, Zhang et al prepared two pigments with ErAlO 3 and Er 3 Al 5 O 12 as the main crystalline phases by the gel-polymerization method and then prepared a pink 3YSZ body via the gel-casting method. 31 It was found that when the colorant of ErAlO 3 is added up to 5 wt.%, the redness value a* of the 3YSZ ceramics reaches the maximum of 13.6. However, the color of 3YSZ ceramics is affected by many factors, such as immersion time and colorant concentration, so it is easy to cause uneven coloring of ceramics with larger sizes, which requires an urgent investigation of the mechanism of indepth color change.…”

“…In 2020, Zhang et al. prepared two pigments with ErAlO 3 and Er 3 Al 5 O 12 as the main crystalline phases by the gel‐polymerization method and then prepared a pink 3YSZ body via the gel‐casting method 31 . It was found that when the colorant of ErAlO 3 is added up to 5 wt.%, the redness value a* of the 3YSZ ceramics reaches the maximum of 13.6.…”

Green nanoceramic pigments based on cobalt chromite doped with Al: Synthesis, characterisation and colour performance

“…Mixtures of certain oxides, such as CoO, ZnO, Al2O3 and Cr2O3, are traditionally the most used pigments. Various shades of colours can be obtained, in stoichiometric quantities, from these reagents calcined at high temperatures [1][2][3][4][5][6]. Quite recently, considerable attention has been paid to inorganic pigments of oxides with the formula AB2O4, in which A 2+ are accommodated in tetrahedral positions, whereas B 3+ are in octahedral positions.…”