Abstract: A horology component (1) for a timepiece, including a first portion (10) and a second portion (20), the first portion (10) comprising one part that is at least partially transparent and at least partially superposed on top of the second portion (20), this second portion (20) taking the form of a massive portion comprising a material capable of emitting at least one emission light wave if excited by at least one excitation light wave, and the at least partially transparent part of the first portion allowing an emission light wave emitted by the second portion (20) to be transmitted at least partially toward the outside of the horology component so that the horology component exhibits at least a first appearance by day and at least one different second appearance by night where the first portion (10) is backlit by an emission light wave emitted by the second portion (20).

Abstract: A horology component (1) for a timepiece, including a first portion (10) and a second portion (20), the first portion (10) comprising one part that is at least partially transparent and at least partially superposed on top of the second portion (20), this second portion (20) taking the form of a massive portion comprising a material capable of emitting at least one emission light wave if excited by at least one excitation light wave, and the at least partially transparent part of the first portion allowing an emission light wave emitted by the second portion (20) to be transmitted at least partially toward the outside of the horology component so that the horology component exhibits at least a first appearance by day and at least one different second appearance by night where the first portion (10) is backlit by an emission light wave emitted by the second portion (20).

Abstract: The invention relates to a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state. The invention furthermore relates to a method for the preparation of a phosphorescent ceramic composite material as defined in any of the previous claims, the method comprising the following steps: preparing a mixture of a metal oxide and a phosphor; fabricating a green body from the mixture; and heat treating the green body in a reducing atmosphere.

Abstract: Watch component made of a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state, the watch component having a surface which comprises an area which shows phosphorescent emission and an area which does not show phosphorescent emission or which shows phosphorescent emission with an intensity which is lower than that of the emission of the other area.

Abstract: The present invention relates to long decay phosphors comprising rare earth activated strontium aluminates and methods for producing them. The phosphors comprise a matrix of the formula Sr4Al14O25 comprising europium as an activator and a further rare earth element as a co-activator, wherein the molar ratio of Al/Sr in the starting materials is in the range of 3.1 to less than 3.5 and the ratio of Eu/Sr is in the range of 0.0015 to 0.01. The process for the preparation of a phosphor comprises the steps of milling the starting materials for the synthesis of the phosphor, the starting materials comprising a boron compound selected from boric acid, boric oxide or a borate salt in an amount such that the B/Sr molar ratio is between 0.1 and to 0.3, treating the milled composition with heat, grinding the block material which is obtained through the heat treatment, ball-milling the crushed material, sieving the material, and washing the material with an aqueous solution.

Abstract: The invention relates to a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state. The invention furthermore relates to a method for the preparation of a phosphorescent ceramic composite material as defined in any of the previous claims, the method comprising the following steps: preparing a mixture of a metal oxide and a phosphor; fabricating a green body from the mixture; and heat treating the green body in a reducing atmosphere.

Abstract: The invention relates to a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state. The invention furthermore relates to a method for the preparation of a phosphorescent ceramic composite material as defined in any of the previous claims, the method comprising the following steps: preparing a mixture of a metal oxide and a phosphor; fabricating a green body from the mixture; and heat treating the green body in a reducing atmosphere.

Abstract: Watch component made of a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state, the watch component having a surface which comprises an area which shows phosphorescent emission and an area which does not show phosphorescent emission or which shows phosphorescent emission with an intensity which is lower than that of the emission of the other area.

Abstract: The invention relates to a persistent phosphorescent ceramic composite material which is a sintered dense body comprising two or more phases, a first phase consisting of at least one metal oxide and a second phase consisting of a metal oxide containing at least one activating element in a reduced oxidation state. The invention furthermore relates to a method for the preparation of a phosphorescent ceramic composite material as defined in any of the previous claims, the method comprising the following steps: preparing a mixture of a metal oxide and a phosphor; fabricating a green body from the mixture; and heat treating the green body in a reducing atmosphere.