SU402766A1 - THERMAL INDICATOR COATING - Google Patents

Description

one

The invention relates to the field of determining the temperature of surfaces and can be used to display and control the surface temperature of objects and heat-generating elements in various installations and electronic circuits operating under high temperature conditions.

Thermal indicator coating is known, which contains organic luminescent substances and an adhesive solvent. The heat-sensitive ingredients of these coatings are colorless organic phosphors, oxazole derivatives, oxadiazole-1, 3,4 and pyrazoline-D2, the luminescence maxima of which lie within 370-450 nm. As the surface temperature rises, luminescence subsides.

The disadvantage of such a thermal indicator coating is that the registration of temperature changes is determined only by the drop in the intensity of luminescence observed when irradiated with ultraviolet light.

To expand the range of thermal indicator coatings, which allow determining the surface temperature over large areas, and to facilitate the control of temperature changes of surfaces, the colored organic compound is introduced into the composition of the proposed coating, having the general formula I and their condensation products with orthodiamines, for example II.

Vco

S.N.S.S.

I

CH N

with AG,

ten

15AH-ei K (. // -,. 1 11 II

(Ar - and Afi-unsubstituted or substituted aromatic radicals; X - hydrogen or functional substituents).

When the temperature of the controlled surface reaches 116-130 ° C, a change in the color of the coating is observed, which is clearly visible to the naked eye. Along with this, the color of the luminescence changes (the absorption and luminescence maxima drastically shift into the shortwave region of the spectrum), and

the intensity of the glow increases.

Thus, in contrast to the known coatings, which allow recording temperature changes only in terms of luminescence quenching, the proposed coatings make it possible to observe them visually, both in color and in luminescence color.

Changes in coloration are clearly visible under daylight and electric illumination, and therefore there is no need to irradiate the surface under study with ultraviolet light.

The proposed coatings, which are solutions of compounds I or II in a xylene solution of methyl butacrylate ether with methyl methacrylate (lacquer CBM-31), are applied to the test surface, on which after evaporation of the solvent a uniform layer is applied to the coating.

Example 1. A solution of 4-1-phenyl-5- (p-methoxyphenyl) -pyrazolinyl-A-3-naphthalic acid (0.005 g) in 5 ml of lacquer CBM-31 is applied on a controlled surface, after evaporation of the solvent a uniform lacquer film is formed yellow color. At 130 ° C

the film becomes discolored and the color of the glow, originally yellow, turns purple. Example 2. A solution of 1-phenyl-5 - ((g-dimethylaminophenyl) -3-1, 8-naphthoylen-G, 2-benzimidazolyl-4 (5) -pyrazoline-D2 is similarly applied to a controlled surface. At 116 ° C, a change in the color of the film from red to yellow is observed. The color of luminescence, originally orange-red, does not occur in yellow-green.

Subject invention

Thermal indicator coating containing an organic thermo-sensitive ingredient and adhesive solvent, characterized in that, in order to expand the range of thermal indicator coatings, which allow to determine the surface temperature over large areas, and facilitate the control of temperature changes of surfaces, a colored organic compound is introduced into the composition of the coating, for example 4- (1,5-diarylpyrazolinyl-L-3) -naphthalic acids.