SU1710529A1 - Composition for preparation of quartz haloid incandescent lamp-tight coating - Google Patents

Description

The invention relates to compositions for the manufacture of thermal and moisture resistant coatings applied to the surface of a bulb of halogen incandescent lamps used in the electrical industry.

The aim of the invention is to increase the moisture resistance of the coating.

The composition for obtaining opaque, coating of quartz gas and log incandescent lamps has the following composition, wt.%:

Copper ferrite 49-53

Sodium silicate or

Kali, 16-22

Aluminum oxide 2-5 Silikazole + hydroxyd

sodium or potassium 2-4

Polymethylsiloxane Water 14-23

Claims (1)

Polymethylsiloxane CHj-Si-O, Sioj was used as a hydrophobic additive, where n varies from about to 1. Polymethylsiloxane's hydrophobicity is due to the orientation of nonpolar methyl groups — they are turned towards the environment on the powder surface, as a result of which the powder is not wetted by water. With the uniform distribution of polymethylsiloxane in the composition, it becomes hydrophobic. Polymethylsiloxane is prepared according to the method, the essence of which is the hydrolysis of a mixture of methyltrichlorosilane and silicon tetrachloride in water-ace3: i At the same time, it produces a tonic medium, with the reaction of aCH3 SiCl 3 - bSiC 4-gH20 HE {CH3Si0 5 | ij SiO ,, 5 Si02DpJh (XtZ) HCl The precipitate is washed from the acid with water to a neutral medium, then calcined at and at 500-550 C for 6-8 h. As a result of heat treatment, the OH groups capable of being wetted with water disappear and it turns out product of composition CH5-Si-0, .5 Csi Oi ". Example. A mixture containing copper ferrite 51 g, a water-repellent additive 6 g, aluminum oxide 3 g was mixed in a ball mill drum for 1.5 hours. Then a solution of sodium silicate (potassium) was added in an amount of 20 g, silicasol + sodium hydroxide ( potassium) 4 g, water 16 s and stirring is repeated (t 2.5 g). The resulting suspension was applied to the outer surface of the lamp bulb by immersing the lamp in the suspension and dried by igniting the lamp for 1-3 minutes. The table shows specific examples of the composition and their moisture resistance. As follows from the table, the proposed composition allows to obtain an opaque, heat-resistant and moisture-resistant 9 coating, which has good adhesion to the lamp bulb walls (up to 100) and a high shielding capacity (low-reflective, black-colored coating with a transmittance, 13, 0). In addition, the manufacture, application and storage of the suspension fully complies with the technological conditions used on semi-automatic production lines of serial quartz halogen incandescent lamps. Claims of the Invention Composition for producing an opaque coating of quartz halogen incandescent lamps, including copper ferrite, sodium or potassium silicate with a silicate module, alumina, silica sol + sodium or potassium hydroxide with a ratio of Si02: NaOH 1 and Si02: KOH 1, i о o lich and so that, in order to improve the moisture resistance of the coating, it additionally contains / methyl aloxane in the following ratio, wt.%: Copper ferrite 9-53 Sodium or potassium silicate () 16-22 Alumina. 2-5 Silica sol + sodium hydroxide or potassium 2-C Polymethylsiloxane C-6 Water 14-23