Heat preservation coating powder syrup for electric arc tube of metal halide lamp

Abstract

The invention provides heat preservation coating powder syrup for an electric arc tube of a metal halide lamp. The heat preservation coating powder slurry is prepared from 1000-1500g of Al2O3 powder, 1500-2000g of deionized water, 20-60g of polyethylene oxide or ammonium polymethacrylate powder, 3-5g of dispersing agent and 0.1-0.5g of wetting agent. The heat preservation coating powder syrup is prepared by comprising the following steps of: (1) stirring 500-750g of deionized water at a high speed, slowly adding polyethylene oxide powder to the deionized water till the polyethylene oxide powder is dissolved, then adding 1000-1500g of deionized water, and stirring at a low speed so as to prepare a polyethylene oxide aqueous solution; (2) adding 1000-1500g of Al2O3 powder, dispersing, stirring the wetting agent, and preparing Al2O3 pasty liquid powder syrup; (3) detecting when the density of the liquid powder syrup is 1.8-2.5g / cm<3> and the viscosity reaches 25-50 seconds for later use. An organic binding agent is decomposed and removed at a high temperature in a lamp manufacturing process so as to prevent a heat preservation coating from being blackened; the initial lighting effect and uminous maintenance rate of the sprayed heat preservation layer are improved, so that the quality of the heat preservation layer is improved, the service life of the lamp is prolonged, the light output energy efficiency is improved, and the energy consumption is reduced.

Description

technical field [0001] The invention relates to a thermal insulation coating powder slurry and a manufacturing process thereof, in particular to a metal halide lamp electric arc tube thermal insulation coating slurry for spraying on both ends of an arc tube discharge chamber. Background technique [0002] The two ends of the discharge chamber of the metal halide lamp arc tube in conventional use can be sprayed with an insulating coating of dry powder flame spraying or water powder slurry spraying made of alumina powder. [0003] Now because of the high material utilization rate, short heating time, low consumption and high work efficiency of water-powder slurry spraying, it will be favored by enterprises. However, in the actual production, the water-powder slurry often uses inorganic binders, so there are still alkali metal ions that will cause quartz glass crystallization, and the expansion coefficient of the quartz glass crystallization point will be more than 10 times hig...

AI Technical Summary

Problems solved by technology

However, in the actual production, the water-powder slurry often uses inorganic binders, so there are still alkali metal ions that will cause quartz glass crystallization, and the expansion coefficient of the quartz glass crystallization point will be more than 10 times higher than that of quartz glass. During the working process of the bulb Due to thermal expansion and contraction of quartz glass, cracks will occur on the edge of the crystallization point of quartz glass, resulting in air leakage, thereby shortening the life of the bulb

Even individual bulbs may explode at the end of their life; the impurities of the inorganic binder will gradually cause Al 2 o 3 Blackening of the thermal insulation coating, resulting in a decrease in the light output and energy efficiency of the bulb

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