AAE Chemie Solvent information

How to use thinners

A thinner consists of different solvent parts. In order to produce high-quality thinners, careful attention must be paid to the exact concentration of each solvent in the mixture. The major groups of solvents that are used as a basis for a thinner are:

The active solvents dissolve the colour. These are highly volatile and in order to keep the active solvents stable, one adds non-actives and/or aromatics. These keep the lacquer system open for a longer time, so that the pigments can settle after application. Non-active solvents serve as thinner. Conductive solvents serve to increase the conductivity of the lacquer system, so that one can spray around the edge without difficulty. The gloss improver is there to increase the gloss effect that comes from the lacquer system.

A good thinner is a well weighed out mixture of the components mentioned above. In a system of varnish for woodwork, the active part is dominant, while in a car repair or industry lacquer system the concentration of aromatics is higher than that of the actives. Woodwork or furniture à higher concentration of actives. Car à higher concentration of aromatics. A quick drying mixture is not desirable for a car repair lacquer, because the faster the lacquer system dries, the less glossy the end result is. If the lacquer system dries too quickly, no pigment layer can be built to settle on the surface of the metal. When the car is then washed, a rapid attack on the gloss will occur because there is no pigment layer to protect it. This is the reason why no binder layer exists that improves the gloss. Here a pigment free zone would have to be created by a second layer of paint: a varnish.

Before a car is painted, its surface has to be treated and every unevenness has to be removed. In most cases, this can be done by filling the surface. After the mending, the surface is flattened using a “wet” or “dry” method. During the wet flattening, one has to be careful not to let the water that was used for the flattening trickle onto the ground, because pigments could enrich there. When dry flattening, we highly recommend using a suction system to protect the painter from inhaling the dust particles.
After the flatting, a dust layer will remain on the surface. This has to be removed before the paint can be applied. One should use a solvent here; it will bind with the dust particles without dissolving the lacquer. The solvent system is called “silicone remover”.
The painter should never remove the dust by hand and after the dust has been removed from the surface, it should not be touched. When the surface has been properly cleaned, it is ready to be painted.

The following techniques should be observed while painting:

Preparing processes before spraying.

The distance between the spray gun and the object that is being painted is very important. The correct distance has to be determined individually for each paint job, depending on the used material, the spray pressure and the size of the jet.

If the spray gun is held too close to the object, the spray angle will decrease and too much of the material will be applied to the surface - often resulting in runs through the paint job. If the spray gun is held too far from the object, the material will almost be dry by the time it reaches the object and the lacquer surface will be rough instead of smooth, resulting in orange peel effect and a loss of gloss.

The spray gun should be brought exactly parallel - not arched to the object by hand. While painting, it needs to waved above the object in slow and smooth movements, and the colour jet of the next spray process should overlap the preceding half.

In order to reach an equal distribution of colour, one needs to spray crosswise: after leading the gun from left to right (horizontal process), the jet head is transposed and a vertical process from top to bottom follows. Because the spray processes are right-angled, this method of gun leading is known as “cross process”. The edges of an object will be sprayed first, and areas that are difficult to reach are sprayed before the main components. The spray stripes should overlap wet in wet.

When applying gloss lacquers, one has to work fast so that the a recently applied layer of paint can absorb a fresh layer before it dries. If the paint is already too dry, a faint passage occurs. If the lacquer is still fresh however, this can be prevented by using thinners. The same goes for when the area of the beginning of the lacquering is reached at the end of the painting process, especially with gloss lacquers at the back roof sides.

Before starting the spraying process, one has to make sure that there are no obstacles on the work floor that could hinder the painter once he has started working, because every hesitation on his part will produce a thicker lacquer layer which, however slight, can potentially cause a formation of runs. One also has to be careful when closing the cover of the colour cup of the gun, so that no lacquer drop falls onto the fresh lacquer.

High-value lacquer materials have a complicated structure, consisting of numerous coordinating single components. They can deal with most minor processing errors, but some will delay or prevent a spotless drying. Three of the most important causes are:

The information given above is based on our practical experience in different parts of the world, where we have worked in different climates, with varying temperatures and humidity levels.

About Solvents

What’s a SOLVENT

Organic solvents can be classified into three groups based on their chemical structure:

An organic solvent contains carbon molecules – one of the basic building blocks of life. Water is also a solvent but is classified as inorganic because its chemical structure does not contain carbon.

About SOLVENTS

Have you ever wondered why paint flows? Or why the ink on the page of a magazine doesn’t smudge? Or even why you are able see through your car window?
The answer is: because of solvents. A solvent is a liquid that has the ability to dissolve, suspend or extract other materials. Solvents make it possible to process, apply, clean or separate materials. Solvents have significantly changed modern living and are an invaluable solution for industries, from companies manufacturing pharmaceuticals and microelectronics, to applications in domestic cleaning and printing products. In fact, without solvents many of the products we use and rely on, from penicillin to industrial paints, would not be up to the standards we demand today. This is why thousands of producers and manufacturers and over 10 million workers in Europe rely on solvents every day: to provide solutions to new manufacturing needs, and ensure excellence in functional performance.

How are solvents made?

With the exception of alcohol, all solvents are produced from oil. The amount of oil used for solvent production is, however, relatively low. Only about 1 - 2% of the world’s oil production is used for solvent production. Many solvents are also recycled, so that they may be used again.

How do solvents work?

Solvents are liquids that are used to dissolve other substances. Water, for instance, is also a solvent that can dissolve many things - but it cannot dissolve oily/greasy substances. Solvents work on the principle of “like dissolves like” e.g. solvents are chemically much more similar to greases than water and can therefore dissolve them more effectively.

Where and how are solvents used?

Thousands of producers and manufacturers and over 10 million workers in Europe rely on solvents every day. From penicillin to industrial paints, without solvents many of the products we rely on would not be up to the standards we demand today.

Uses & benefits of solvents

The largest demand for solvents comes from the paint and coatings industry; it relies on almost two million tons every year. But the pharmaceutical sector is also a growing market, showing a steady increase in demand year after year, because of solvents' invaluable contribution to the purity of modern medicines.

History of SOLVENTS

The first man-made solvents were almost certainly hydrocarbons, such as turpentines derived from wood sources, and ethanol from wine spirits. Ancient civilizations discovered that by fermenting vegetable matter, such as grapes or sugar cane, they could produce ethanol. In many ways it looked and behaved like water; in other ways it was very different and proved invaluable for dissolving oils and resins. Ancient Syrians found that heating wood sealed away from the air resulted in a variety of tars and liquids. One of the liquids, now called methanol by chemists, proved to be a useful solvent and fuel.


Solvents were also discovered for medicinal purposes. The “Book of the Ten Treatises on the Eye” (Assyrian Hunayn Ibn-Ishaq 809-873 A.D.) contains recipes for eye compresses in which Hunayn described methods of preparation, techniques, ingredients and solvents used. The Egyptians may have used solvents in the production of cosmetics. Chemists from L’Oreal have worked together with scientists from the Louvre in Paris to analyse make-up from the 2nd millennium. In doing so, they learned that the black eye make-up contained components that did not exist in nature, which means that the Egyptians synthesized these substances. The complicated science of wet chemistry – working with solvents – seems to date as far back as to the time of the pharaoh’s.


The use of solvents in the production of perfume reached an important turning point when, in 1900, Antoine de Chiris and Roure Bertrand Fils presented essences extracted with volatile solvents at the Paris World Fair, for which they consequently won the World's Fair Grand Prize. With industrialization, the mass market for cosmetics was born. At the same time, other large-scale uses were also developed – first with coal and eventually with oil-derived products. The use of synthesized solvents, cost effectively and consistently produced, has over the past one hundred years enabled the development of an enormous variety of goods that we nowadays take for granted, but without which modern living standards would be drastically reduced.