Lead minium or lead oxide (Pb 3 O 4 ) is a chemically resistant substance insoluble in water and sulfuric acid. It is best known as a high-quality natural pigment of orange or brick-red color, which is part of anti-corrosion primers and paints that are widely used in painting practice.
Description
Lead mead (GOST 19151-73) is a heavy fine-crystalline powder with a particle size of 2 to 10 microns, which is obtained in the process of thermal oxidation of the glta semi-finished product and lead powder with atmospheric oxygen. The substance has a high density, is the strongest oxidizing agent.
The latter property determines the scope of its application as an anticorrosive agent in soils, putties, paints, putties, etc. When the meerk enters into a reaction with iron, a dense impermeable oxide film forms on the metal surface, which reliably protects the treated surfaces of metal structures from rust. It is produced only in chemical plants. The substance is quite toxic and, in accordance with the Russian standard, is assigned to the first
hazard class, therefore the “Surik Lead” paint made on its basis is prohibited for use in residential and
public buildings.
Application
The main purpose of lead pigment is to provide increased anti-corrosion properties of paintwork materials, which are used for metal structures and surfaces, including those damaged by rust or with residues of scale.
These materials are actively used in shipbuilding for priming and painting exterior surfaces exposed to salt water and atmospheric phenomena. Lead minium is not afraid of aggressive environments, has high adhesion, and is an effective
corrosion inhibitor. It can also be used to create a protective decorative coating for reinforced concrete and concrete structures. In addition, lead red lead is necessary for the manufacture of batteries, as well as in the production of crystal and some grades of protective, radiation-resistant and
optical glass. In the chemical industry, it serves as a reagent in the production of acetate, carbonate and other lead compounds. Thickly grated lead red lead is the basis of resistant putties and coatings, which are used in the assembly of oil, steam and water pipelines. The practice of using the aforementioned pigment for protection against gamma radiation, as well as for the production of matches and some termite
explosives.
The method of application of paint "Lead lead"
Before use, the paint must be thoroughly mixed and, if necessary, diluted to the desired viscosity with solvents: solvent or white spirit. You can use a mixture of toluene with solvent in a ratio of 1: 1. The surface to be painted must be cleaned and degreased. The finished paint, the temperature of which should not be lower than 15 ° C, should be applied in two layers with a brush, roller or spray gun. In this case, the air temperature (from 5 to 35 degrees) should be taken into account. At least 2 hours are allowed to dry each layer. During painting, the minium should be stirred as often as possible, in order to avoid the deposition of heavy particles of this substance to the bottom of the container.
Pigment packaging, storage and transportation
Lead minium is packaged in steel flasks, wooden or plastic barrels, plywood, steel or cardboard-navivny drums, special soft disposable containers.
The container must be waterproof. It is transported by any means of transport in compliance with the rules of protection against atmospheric moisture. Lead pigment is stored in packaged form in dry closed warehouses at a temperature of -40 ° C ... +40 ° C for no more than 1 year from the date of manufacture. Given that lead red lead is toxic, the necessary safety precautions should be taken during transportation and storage.