Process for preparing water resistant luminous pigments
AssigneeMatsui Shikiso Chemical Co., Ltd.
InventorsYosuke Kitagawa, Ryuichi Hoshikawa
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Abstract
A process for preparing a water resistant luminous pigment with durability, characterized in that a luminous pigment, in which an oxide matrix comprising at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn and at least one element selected from the group consisting of B, Al, P and Ga is doped with at least one rare-earth metal element, is allowed to an acid treatment under the condition of pH of not more than 3 using at least one acidic compound selected from the group consisting of acids and acid generating compounds, and is subsequently allowed to an alkaline treatment under the condition of pH 4-9 using at least one alkaline compound selected from the group consisting of alkalis and alkali generating compounds.
Claims10
A process for preparing a water resistant luminous pigment, characterized in that a luminous pigment, in which an oxide matrix comprising at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn and at least one element selected from the group consisting of B, Al, P and Ga is doped with at least one rare-earth metal element, is acid treated under the condition of a pH of not more than 3 using at least one acidic compound selected from the group consisting of acids and acid generating compounds, and is subsequently given an alkaline treatment under the condition of a pH of 4-9 using at least one alkaline compound selected from the group consisting of alkalis and alkali generating compounds.
Dependencies are inferred from the claim text.