In technical definitions, coating thinner or solvent is a part of the coating formulation that is removed from it in the form of product delivery to the customer and is delivered along with the product during spraying so that the customer can apply the coating as desired.
. Color compatibility
. Diluting the coating in the smallest possible volume
. Non-toxic and low risk for the operator
. High leveling power
. Maximum compatibility with the environment
. Volatile according to the nature of the color
Therefore, according to the definitions mentioned at the beginning, the thinner must be compatible with the coating resin base, this compatibility in the design of a thinner is based on knowing the resin and its film drying mechanism. Types of solvents in the coating industry include the following:
. Aliphatic hydrocarbon solvents such as super gasoline, solvent 402 or white spirit
. Ketone solvents such as acetone, MIBK, MEK and cyclohexanone
. Light and heavy aromatic hydrocarbon solvents such as: toluene, xylene, Soloso 100, Soloso 150 and Soloso 200 and monostyrene.
. Ester solvents such as: methyl acetate, ethyl acetate, butyl acetate, methoxypropyl acetate MPA, butyl glycol acetate BGA, butyl diglycol acetate BDGA, methoxy ethyl acetate
. Alcoholic solvents such as: methanol, isopropyl alcohol, butyl glycol, normal butanol.
. Oil solvents such as: DOP, DBP, DINP
Almost all the solvents used in the solvent-based coating industry include the above. Thinner is actually a mixture of two or more samples of the above solvents, this mixture is designed in such a way that it helps to improve the quality of spraying or coatinging coating, gives the most alignment and evaporates in the best possible time and remove the color from the film.
In coatings that are applied with a spray gun, the thinner must dilute the coating in the minimum amount used, this means that the cut of the thinner must be so favorable that it can easily bring the coating to a spraying viscosity of 15 to 17 seconds of cup 4 DIN. This demand is due to the fact that the better the cut of the thinner, the better the dry film solidity and the glossier the product will be. Definitely, this type of thinner will have the properties of alignment and prevention of stinging or the so-called blister.
In the beginning, it was mentioned that a thinner should be directly related to the base of the coating resin and its hardening mechanism, so that the maximum compatibility is possible.
For example, oil coatings are based on long oil alkyd resin and these resins are soluble in white spirit with 70% solids. So, the choice of solvent for this type of coating is to use aliphatic hydrocarbon solvents such as super gasoline and solvent 402. Also, due to its polar properties, nitrocellulose varnish should be compatible with acetic and ester alcohol solvents, and on the other hand, it is incompatible with aromatic and aliphatic hydrocarbon solvents. In the same way, by knowing the color structure, we can choose the right solvent, in designing a thinner with a mixture of several solvents with different families, we actually want to make the most of the properties of individual solvents in improving quality, for example, in the design of instant thinner, in addition to alcoholic solvents, ester and light aliphatic hydrocarbon solvents are also used, also, to adjust the thinner’s jumping point, alcohol solvent and heavy or fatty ester are added in smaller amounts to prevent overspray during spraying.
Instant thinners
Polyurethane thinner
Instant thinners or thinners for nitrocellulose coatings and acid cure polyesters are divided into 10000, 12000, 15000 and 20000 based on the percentage of methanol alcohol, and the higher the number, the lower the methanol content, and instead, its ester, ketone and glycolic solvents are higher. from a qualitative point of view, as we move towards 20000, the quality of thinner cutting and jumping improves, and thinner’s dependence on the temperature of the surrounding environment decreases, On the other hand, relying on experience and technical knowledge, thinner 10000 can be designed so that the customer gets the best result with it, and this depends to some extent on the formulation of the color used. Rangin Kimia Company has designed its products in such a way that it shows the most compatibility with the thinners available in the market, and if the customer uses these products with the thinners produced by the company, the quality results will definitely exceed the customer’s expectations. Because by looking at the product’s specialized formulation, their thinners are designed to give the best possible quality.
Many thinner manufacturers in the market simply do an experimental mixture of solvents, or to reduce the price, they use cleaning solvents in part of the formula, whose long-term effects on the color quality cannot be predicted. Rangin Kimia color thinners are always prepared and produced from high purity solvent and its quality benefits are accompanied by experience and expertise and prevent any possible damage.
One of the features of Rangin Kimia’s instant thinners is their four seasons and this lack of dependence on the temperature of the workshop environment shows the effective use of its ester and ketone solvents and the goal is only to improve quality and customer satisfaction, in addition, polyurethane thinners with codes 100 and 50 have been proven by experience to give a constant quality in any season and temperature and are completely compatible with any type of polyurethane coating, even imported ones, and leads to the best drying and hardening, One of the main features of polyurethane thinner is that you should never use alcohol solvents in it, because the thinner’s free alcohol prevents the hardening of the polyurethane color by reacting with the isocyanate hardener.
The characteristic of instant thinner is that its acid number must always be zero or minimum, because the pH of a thinner has a direct relationship with the degradation of the coating film in the future, for example, if the acidity of a solvent such as methyl acetate in the thinner formula is not controlled, then the free acetic acid will act as a catalyst in the thinner environment and will show itself as an excess hardener in the acid cure polyester, which causes unconventional early drying and hardening of the film in a minimum time, and this will cause cracks in the final film after some time, of course, this type of damage will have other causes, such as the use of flare solvents (petrochemical gas condensate output) and purification solvents in the thinner formula, which again is due to their acidity, and sulfur compounds such as thiol, thiophene, catalyst acid of distillation tower, vaporized compounds such as sodium sulfate salts such as excess catalyst in acid cure polyester will lead to cracking and peeling in the future.
Therefore, Rangin Kimia Group produces its high-quality thinners by relying on full knowledge to avoid any possibility of problems, and experience has proven that customers who use our products with the company’s own thinner have not suffered any problems or damages, this is the true meaning of quality, that is, foresight, relying on technical knowledge and experience to prevent possible damage, quality will always have its steady customers.
Production and collection: Rangin Kimia Industrial Complex
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