An optical converter is provided that has both a stable colour even at highest luminous powers and a high luminous efficiency. The optical converter includes a ceramic element that is fluorescent so that light of a first wavelength is absorbed in the ceramic element and fluorescent having longer wavelength light is emitted. The ceramic element includes pores spatially irregularly distributed within the ceramic element. The distribution of the pores within the ceramic element is inhomogeneous so that the radial distribution function of the pore locations deviates from unity and has a maximum at a characteristic distance, the maximum having a value of at least 1.2.

Systems and methods for printing a luminescent 3-dimensional object. The method includes mixing a dry cementitious composition with water, the dry cementitious composition comprising a cementitious binder, conveying the mixture to a print head, applying the mixture and one or more luminescent compounds from the print head to form a luminescent 3-dimensional object, and curing the luminescent 3-dimensional object.

Luminescent concrete compositions containing cement, fine aggregates such as sand, and a phosphor such as strontium aluminate. Glow-in-the-dark concrete products made therefrom and methods of producing such concrete products are also specified. The glow-in-the-dark concrete products demonstrate good mechanical strength (e.g. compressive strength) and skid resistance. The addition of phosphorescent strontium aluminate provides luminance that persists for up to 10 hours to the concrete products.

A multicolor light-storing ceramic for fire-protection indication and a preparation method thereof are provided. The preparation method includes: adding a glass based raw material, a light-storing powder, a dispersant and an alumina powder into a granulator, adding water mixed with a pore-forming agent and then mechanically stirring for granulation; adding a plasticizer after the stirring of 4?8 h, and continuing the stirring for 1?3 h to thereby obtain a mixture; packing the mixture into a mold and performing tableting; demolding and obtaining a light-storing self-luminous quartz ceramic by drying and firing using a kiln; printing a pattern onto a surface of the ceramic and then curing to obtain a light-storing ceramic for indication sign. Using an industrial waste glass has advantages of low sintering temperature and green environmental protection; dispersed pores and alumina introduced as scattering sources improves light absorption efficiency, fluorescence output phase ratio and light transmission of the ceramic.

A fluorescent member includes: a plurality of fluorescent particles; an inorganic binder; and a plurality of pores. An upper surface of the fluorescent member is a light extraction surface of the fluorescent member. The plurality of pores are localized in a vicinity of at least one of the plurality of fluorescent particles in a cross section that is parallel to the upper surface of the fluorescent member and extends through the fluorescent particles and the pores.

A method of monitoring conditions in a wellbore by disposing capsules with a signaling agent downhole, and monitoring the presence of the signaling agent released from the capsules that escape the wellbore. The capsules are formed by combining immiscible liquids, where one of the liquids contains the signaling substance, and each of the liquids contains a reagent. When combined, the liquids segregate into a dispersed phase and a continuous phase, with the dispersed phase having the signaling agent. The reagents react at the interfaces between dispersed and continuous phases and form polymer layers encapsulating the signaling agent to form the capsules. When disposed downhole, such as in casing cement, the capsule membranes can burst under pressure or temperature to release the signaling agent. Adjusting relative concentrations of the reagents varies membrane strength and permeability.

Luminescent concrete compositions containing cement, fine aggregates such as sand, and a phosphor such as strontium aluminate. Glow-in-the-dark concrete products made therefrom and methods of producing such concrete products are also specified. The glow-in-the-dark concrete products demonstrate good mechanical strength (e.g. compressive strength) and skid resistance. The addition of phosphorescent strontium aluminate provides luminance that persists for up to 10 hours to the concrete products.

Disclosed is a colored luminescent composite pigment including an association of at least one luminescent pigment having an average particle size of between 50 and 2000 m and at least one coloring agent. Also disclosed are compositions and materials including the pigment, to the method for the production thereof and to the use of same for coloring materials, particularly of a hydraulic binder composition.

A method of making an identifiable gypsum-based building product, includes incorporating a suitable amount of an optically identifiable marker into the product to be sensed by a conventional detecting device; applying the product with the marker in a conventional manner in the course of building construction, creating a finished building product; and analyzing the finished building product and optically detecting the presence of the marker in real time onsite.

The present invention relates to floor levelling compositions which can be mixed with water and comprise fluorescein or a derivative thereof. The present invention further relates to the use of fluorescein or fluorescein derivatives as indicator for the readiness for being covered of a floor levelling composition mixed with water.