METHOD OF OBTAINING RETROREFLECTIVE COATING IN ELECTROSTATIC FIELD AND APPARATUS FOR DEPOSITING MICROSPHERICAL RETROREFLECTIVE PARTICLES IN ELECTROSTATIC FIELD

摘要

FIELD: physics.SUBSTANCE: coating is obtained in an electrostatic field by successive deposition of layers. A support layer from a polymer powdered composition is deposited in an electrostatic field, followed by heat treatment at temperature below the temperature of formation of the polymer powdered composition. An information mark of the corresponding colour is formed on top of the support layer on a mask from similar polymer powdered composition with heat treatment similar to that of the support layer. Subsequent deposition of a reflecting layer with optical microspheres is carried out in an electrostatic field. After depositing the reflecting layer, final heat treatment is carried out until fixation thereof, followed by deposition of a protective layer from a transparent polymer material. The apparatus has a housing (1) with a handle (2), a hopper (3) for feeding microspherical particles, a shaft (4) with a channel (5) for flow of microspherical retroreflective particles and a voltage multiplier (6) with a corona electrode (7) lying in the outlet of the shaft (4). A spray seat includes a cylindrical housing (8) with a conical section at the outlet, in which in series, in the direction of flow, there is a central channel (9) with a closed end at the outlet, and at the inlet connected to the channel (5) for flow of microspherical retroreflective particles, an annular cylindrical channel (10) which transforms at the outlet into an annular conical channel (11), respectively formed by a cylindrical bushing (12) and a conical reflector (1) at the outlet, lying coaxially with the housing (8). The central channel (9) is connected to the annular channel (10) at its inlet by tangential holes (14) on the circular surface of the cylindrical bushing (12). On the surface of the conical reflector (13) there are grooves (15) for ordered movement of microparticles on the annular conical channel (11) to the article, as well as under the action of air ejected through a row of holes (16) and (17) on the housing (8). The central channel (9), at the inlet of the spray seat, has a section (18) which narrows in the direction of flow, and at the end surface of the central channel (9), there is a conical splitter (19) with a vertex which is directed opposite the flow of microspherical retroreflective particles.EFFECT: invention simplifies the process, improves quality and prolongs the service life of the article.9 cl, 4 dwg