- Materials & Industrial Technology
Manufacture of aerosol paints
Aerosol paint, also called spray paint, is a type of paint that comes in an aerosol container for spraying onto surfaces. Aerosol paint leaves a smooth surface, unlike many rolled or brushed paints. Spray painting is faster and provides a more uniform application. There are two types of sray paints. Industrial paints, relies on special air compressors that break the paint particles into a fine mist. Commercial paints are self-contained aerosol cans that use liquefied gasses to atomize the paint.
In modern times, paint (spray paint) and marker pens have become the most common used graffiti materials. Art is free form of expression and graffiti is art. It is the act of writing or drawing on walls to send a message to the general public. Now, it is considered as the most popular art among the streets in every part of the world. Some of the famous artists in the graffiti culture are: Banksy (probably the most well-known street artist in the world), Blek le Rat, Keith Haring, Zephyr, etc. Caleb Neelon (“The History of American Graffiti”) says there were fewer options for high-quality spray paints in those days. But in the late ’90s, graffiti writers noticed the influx of higher-quality paints. They were made by companies like Montana (Spain), Molotow (Germany) and Ironlak (Australia).
The concept of an aerosol originated since 1790. Spray cans, constructed from heavy steel, were being tested since 1862. They were too bulky to be successful.
In 1927, engineer Erik Rotheim patented the first aerosol can and the valve that could hold propellant systems.
Edward Seymour invented canned spray paint in 1949. The first paint color was aluminum. Edward Seymour founded Seymour of Sycamore to manufacture his spray paints. The company began customizing its own equipment. It expanded into new businesses, like industrial-machine markets. Spray paint came in small, easy-to-conceal cans. It was two-in-one - paint and brush, it dried quickly and worked well on building materials and subway cars.
Pigments. They are materials used to provide color and opacity. Solvents are the liquids that carry the rest of paint ingredients. Propellants are gasses that force the paint out of the can by expanding rapidly when the valve is opened. Other materials are included to stabilize the pigment dispersion and to prevent corrosion in the can.
The technology behind the aerosol can is amazing. An easy-to-hold sealed aluminium pressurised container with a push-button valve release on the top. Each paint can has a small metal ball, called a pea, that mixes the paint when the can is shaken.
The Manufacturing Process
The first step in the manufacturing process is to prepare the liquid concentrate in large metal tanks. This means mixing the liquid ingredients with large impeller type mixers driven by electric motors. The second step is ensuring that solid pigment particles are properly dispersed. Necessary for this purpose is using special mixing equipment such as a ball mill or a roller mill (two rotating metal cylinders). When the pigments have been wetted, the slurry can be added to the liquid concentrate in the batching tank. The mixture is stirred until it’s homogenous. When the batch is ready it can be transferred to a filling tank. The filling processes used for aerosols is automated. Jets of compressed air blast away any dust or dirt that may be in the cans. After filling the cans proceed to a gassing device that injects liquefied propellant into the can and crimps the valve against the rim of the can to seal it shut. The cans travel through hot water so they can be checked for leaks. At the end, an overcap is fitted over the valve to protect the aerosol from accidental activation.
Manufacturers struggle to find new ways to market their products. The best spray paint brands at this moment are Montana spray cans, Ironlak spray paint, Molotow Paints, MTN cans, Kobra, etc.
Given the growing market demand, it is worth considering the opportunity to invest in this sector. For instance by purchasing an already established company. Buying a manufacturing company can be a lot of work, but is often seen as a rewarding move for those who decide to run their own business.