RU2000627C1 - Gaseous-discharge lamp - Google Patents

Abstract

Use: in the manufacture of low pressure gas discharge fluorescent lamps. SUMMARY OF THE INVENTION: A tubular flask of optically transparent material is filled with an inert gas and mercury. The first layer of a substance absorbing radiation in the long-wave ultraviolet region of 300-400 nm is deposited on the inner surface of the flask. from a suspension based on titanium dioxide; and a second layer from a phosphor suspension. The latter contains magnesium orthophosphate — strontium activated by tin, and zinc orthosilicate activated by manganese. Strontium halophosphate activated by antimony, yttrium oxide activated by europium were introduced into the phosphor suspension, in the following ratio of components, wt.%: Strontium halophosphate activated by antimony 53-61, magnesium orthophosphate strontium activated by tin 27-34; zinc orthosilicate activated with manganese 3-6, yttrium oxide activated with europium 2-6, strontium chlorophosphate activated with europium 3-9. The specific gravity of the first titanium dioxide-based layer is in the range 0.25-0.50 mg / cm2. 2 tab. 73 C

Description

The invention relates to the electrical industry and can be used in the manufacture of gas discharge low pressure fluorescent lamps.

A gas discharge lamp with a single-layer phosphor coating on the inner surface of a flask tube is known, in the production of which a phosphor suspension is prepared using the composition ФЛ Ц-610-3900-4, consisting of a mixture of magnesium or strontium-strontium activated tin , barium titanate phosphate, calcium halophosphate activated

antimony and manganese, zinc orthosilicate, activated with manganese on a water-soluble or organosoluble binder, is coated, dried and the binder is burned out from the phosphor layer 1.

Lamps made by this method have low color rendering index and the presence of radiation in the long-wave ultraviolet region of 300-400 nm, which is about 0.23 watts.

The closest in technical essence and the achieved result to the declaration of o o o o

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In addition, there is a gas discharge lamp containing a tube bulb of an optically transparent material filled with inert gas and mercury, on the inner surface of which is coated, reflecting visible light and absorbing ultraviolet radiation. A second layer of a phosphor luminescent in the visible range of the spectrum is deposited on this layer. The first layer is made of titanium oxide and deposited on the surface of the flask in an amount of 1.2 mg / cm. The second layer contains a luminescent composition consisting of a mixture of strontium borophosphate activated with europium 2 (Sro.98 Euo, 02 O) -0.84 PjOs 0.16 B20s; strontium orthophosphate, tin activated magnesium (Sr, Md) s (P04) 2: Sri; zinc silicate activated with manganese (Zna SIO4: Mn) and calcium halophosphate activated with antimony and manganese, Caio (P04) 6 (F, Cl) 2 Sb, Mn (6100K) 2.

A disadvantage of the described lamp is the large thickness of the first layer and the high cost due to the presence in the coating of a large amount of expensive phosphor activated by a rare-earth element.

The aim of the invention is to reduce the cost of discharge lamps and increase their light output.

The goal is achieved in that in a known gas-discharge lamp containing a tubular flask of optically transparent material, filled with a gas of mercury and mercury, on the inner surface of which a first layer of a substance absorbing radiation in the long-wave ultraviolet region 300-400 nm is deposited from a suspension based on dioxide titanium and a second layer from a phosphor suspension containing tin activated magnesium or strontium orthophosphate and zinc orthosilicate activated by manganese, according to the invention, in the phosphor suspension nzii introduced galofosfat strontium, activated with antimony, yttrium oxide activated with europium and strontium chlorophosphate - barium, activated by europium, the following ratio of components. wt.%:

Strontium halophosphate,

activated

antimony53-61

Strontium Magnesium Orthophosphate Activated

tin27-34

Zinc Orthosilicate,

activated

manganese3-6

Yttrium oxide

activated

europium 2-6

Strontium Chlorophosphate - Bari,

activated

europium 3-9

in this case, the specific gravity of the first layer based on titanium dioxide lies in the 0 range of 0.25-0.50 mg / cm2.

For experimental verification, fluorescent lamps were made in which the first layer of titanium dioxide had three different thicknesses, and for the second layer 5, four compositions of the phosphor mixture were used, which are shown in Table 1.

The use of strontium halophosphate activated by antimony increases the magnitude and stability of the light flux, and also 0 improves the color rendering of the lamps. Its use within the specified limits is due to the specified color temperature of the lamps (5500 ± 500) K. When it is introduced into the mixture of less than 53%, a shift to more than 5 low color temperatures occurs, and when its content exceeds 61%, the color temperature goes beyond the upper limit.

The use of the indicated limits for the content of yttrium oxide activated with 0 europium is due to the need to achieve high luminous flux values and color rendering indices. At the same time, a content of yttrium oxide activated by europium in the composition of less than 2% leads to a 5 decrease in the luminous flux and a deterioration in color reproduction, and when used above 6%, the cost of the lamps increases.

The introduction of strontium chlorophosphate - barium activated by europium improves the color rendition of lamps. Its content is due to the indicated color temperature limits. An increase in its content shifts the lamps to a region of higher 5 color temperatures, and a decrease to a region of lower color temperatures.

The use of a titanium dioxide protective coating in fluorescent lamps with a specific density of 0.25-0.50 mg / cm 0 provides reliable protection against ultraviolet radiation in the region of 300-400 nm. The fraction of radiation does not exceed that for incandescent lamps of the corresponding power.

5 The use of the specified limits of the specific density of the protective coating is due to the need to preserve the proportion of ultraviolet radiation at the specified limits at the maximum lamp efficiency. In this case, the decrease in specific

a density of the protective coating of less than 0.25 mg / cm leads to an increase in the fraction of radiation in the long-wave ultraviolet region, and an increase in the density of the protective coating of more than 0.50 mg / cm2 leads to a decrease in the light output of the lamps.

PRI me R. 600 g of glass balls with a diameter of 18-25 mm, 100 ml of varnish based on an aqueous-alkaline solution of a copolymer of methyl methacrylate and methacrylic acid with a viscosity of 0.088 Pa s at 293 K, 50 g of titanium dioxide are loaded into a 2-liter porcelain drum. The resulting mixture is then milled for 25 hours at a drum speed of 60 minutes.

Thereafter, the resulting suspension was applied to the tube of a fluorescent lamp by a standard procedure. The specific load of the protective coating is 0.25 mg / cm2.

To deposit a second phosphor layer, 600 g of glass balls of 18-25 mm diameter, 61 g of strontium halophosphate activated with antimony in an amount of 0.8 May are loaded into a 2 liter porcelain drum. %; 27 g of magnesium orthophosphate - strontium activated by tin (0.4 wt.%); 5.0 g of zinc orthosilicate activated by manganese (4 wt.%); 4.0 g europium activated yttrium oxide (6 wt.%); 3.0 g of strontium barium chlorophosphate activated with europium (4 wt.%), 60 ml of varnish based on a copolymer of butyl methacrylate and methacrylic acid dissolved in butyl acetate, with a viscosity of 0.01 Pa s at 293 K and 1% barium tetraphosphate . Then the resulting mixture is ground for 20 minutes at 60 minutes.

After that, the obtained phosphor suspension is applied according to the standard procedure to the tube of a fluorescent lamp over a protective coating. The specific load of the bilayer coating is 3.5-4.0 mg / cm2. Binding of the binder is carried out simultaneously from two layers at 540-560 ° C for 5 minutes with the addition of heated air.

Using the proposed composition, gas-discharge low-pressure fluorescent lamps with a power of 36 W were manufactured.

Table 2 shows the data characterizing the luminous efficiency of fluorescent lamps with a radiation power in the long-wave ultraviolet region of 300-400 nm.

A new method for applying two-layer coatings increases the light output of lamps by up to 1.5%. In addition, in the proposed luminescent composition, in comparison with the prototype, the content of expensive phosphors activated by rare-earth elements is reduced from 46 to 7-12%, which reduces its cost and the price of lamps with its use.

Their color temperature is 5500 K with a high color rendering index.

Such lamps are especially needed for lighting museums and art galleries, where a high degree of color difference is required and, at the same time, a reduced power of ultraviolet radiation, which accelerates the process of ink destruction.

Claims (1)

The claims A gas discharge lamp containing a tube flask made of optically transparent material filled with an inert gas and mercury, on the inner surface of which a first layer of a substance absorbing radiation in the long-wavelength ultraviolet region 300–400 nm is deposited from a suspension based on titanium dioxide and a second layer from a phosphor suspension containing tin activated magnesium-strontium orthophosphate, activated zinc and orthosilicate of zinc activated with manganese, characterized in that, in order to reduce the cost, the composition of the phosphor suspension is introduced nygalofosfatstrontsi, activated with antimony, yttrium oxide activated with europium and strontium chlorophosphate -bar, activated with europium, with the following component ratio, wt.%: Strontium halophosphate, activated antimony53-61 Orthophosphate Magnesium-Strontium tin activated Zinc Orthosilicate, activated manganese3-6 Yttrium oxide activated by europium 2-6 Chlorophosphate strontium bari activated by europium 3-9 and the specific gravity of the first layer based on titanium dioxide is in the range 0.25-0.50 mg / cm2. Table 1 table 2