Blue-violet ceramic pigments based on Co and Mg Co2−xMgxP2O7 diphosphates

Synthesis and characterisation of Ba(Zn1−xCox)2Si2O7 (0 ≤ x ≤ 0.50) for blue-violet inorganic pigments

“…Accordingly, selection of an appropriate host lattice, minimization of the Co content and strong colouring performance are necessary, when Co is applied to colour pigments. Although many studies on the reduction of the amount of Co in the pigments have been reported, [10][11][12][13][14] almost of them are on the blue pigments and there are only a few reports on the violet pigments. 13,15,16 Generally, the colour of inorganic pigments is mainly affected by the crystal eld, generated by the ions surrounding the chromophore.…”

Synthesis of non-toxic inorganic blue pigments in the melilite-type structure

“…While various ions like Cu 2+ , Fe 2+/3+ , Co 2+ , Mn 3+/5+/6+ , Ni 2+ , V 4+ , and S 3À are known to function as blue chromophores, currently, the most used inorganic blue pigments are based on cobalt compounds, such as cerulean blue (CoOÁnSnO 2 ), cobalt silicate blue (Co 2 SiO 4 ), or ''Cobalt blue'' (CoAl 2 O 4 ). [1][2][3][4][5] These materials exhibit exceptional properties providing intense hues in combination with a high stability against heat and chemicals. For these reasons, they can be used in both indoor and outdoor applications without a loss of color quality over time.…”

Intense Blue Colors in Wolframite‐Type Co2+:MgWO4 Oxides Through Distortion in Co2+ Octahedra.

“…The commonly used blue pigments are Co‐aluminate, (Co,Zn)‐aluminate, (Co,Cr)Al 2 O 4 and also (Co,Zn) 2 SiO 4 willemite and in these pigments the intense blue color is associated to Co 2+ in tetrahedral sites ,. In contrast, when Co 2+ ions are accommodated in octahedral sites the color obtained is not so intense and is often violet or pink, as it occurs in Co 2 SiO 4 olivine or in some phosphate‐based pigments . Cobalt based green colored inorganic pigments are also available.…”