Fluorescent lamp and lighting device

Abstract

Provided is a fluorescent lamp hardly generating peel-off or a crack of a protecting film at the time of bending a glass bulb after forming of the protecting film and a phosphor layer. The fluorescent lamp is provided with a translucent discharge vessel made of a glass bulb formed in a non-straight-tube shape by the bending process; the protecting film formed on an inner face of the translucent discharge vessel before its bending process with non-luminous material particles having high reflective characteristics with an average particle size of 1 [mu]m or more as a main component; a phosphor layer formed before the bending process of the translucent discharge vessel on a surface side of the protecting film with a binder added by 3.0 to 5.0 mass% with a melting point of 900[deg.]C or less; a pair of electrodes arranged so as to generate discharge inside the translucent discharge vessel; and a discharge medium sealed inside the translucent discharge vessel. Since the binder with the melting point of 900[deg.]C or less is added to the protecting film 2 constituted by the non-luminous material particles with an average particle size of 1 [mu]m or more, intensity of the protecting film 2 can be improved without degradation of a light output.

Description

technical field [0001] The present invention relates to a fluorescent lamp in which a non-straight tube is formed by bending after forming a phosphor layer, and an illuminating device using the fluorescent lamp. Background technique [0002] The known ring-shaped fluorescent lamp first forms a phosphor layer on the inner surface of a straight glass electron tube, then welds a pair of electrodes at both ends of the glass electron tube, and then bends it to form a ring shape, and then evacuates the inside of the glass electron tube and seals it Made of mercury and argon. In such a circular fluorescent lamp, a protective film is generally formed on the inner surface of the glass tube before bending, and a phosphor layer is formed thereon. This protective film is formed to prevent the alkaline components (mainly sodium) in the glass tube from moving and depositing from the surface of the tube due to ultraviolet radiation, that is, the problem of deterioration of the phosphor du...

AI Technical Summary

Problems solved by technology

[0006] However, when the phosphor layer formed on the surface side (discharge space side) of the protective film is bent, the peeling phenomenon of the phosphor film is likely to occur mainly on the part where the glass protrudes.

Therefore, there is a problem of poor appearance, and it is necessary to increase the strength of the phosphor layer.

[0007] Moreover, when pinhole-like peeling and cracks (cracks) occur on the protective film, the inner surface of the glass tube will be exposed on the phosphor or discharge space side, so alkaline components and phosphor or The problem of mercury reacting and coloring

Images