The previous article introduced the function and dosage of thinner,Click to read: The role and dosage of diluent, below, we introduce which organic solvents can be used to prepare dilutions agent.
The composition of the thinner is not a technical secret, because the corresponding composition is found in the MSDS that the coating manufacturer must provide or disclose (although the composition of the composition in the MSDS usually gives a range).
Let’s look at the commonly used ones first What are the organic solvents used to prepare non-reactive diluents?
①Aliphatic hydrocarbons: Hydrocarbons in which the carbon atoms in the molecule are connected to form a chain-like carbon skeleton, with both ends open and not forming a ring, are called open-chain hydrocarbons, or chain hydrocarbons for short. Because fats have this structure, they are also called aliphatic hydrocarbons. oftenThe most common aliphatic hydrocarbon solvents include 200# solvent gasoline (rosin water, mineral spirits, white water), 140# solvent gasoline, etc.
②Aromatic hydrocarbons: Aromatic hydrocarbons usually refer to hydrocarbons containing benzene ring structures in their molecules. It is a type of closed chain. It has the basic structure of a benzene ring. Most of the compounds discovered early in history had an aromatic taste, so these hydrocarbons were called aromatic hydrocarbons. Hydrocarbons discovered later that did not have an aromatic taste also used this name. Aromatic hydrocarbon solvents include: benzene, toluene, xylene (usually a mixture of isomers including ethylbenzene), trimethylbenzene (usually a mixture of isomers), heavy aromatic hydrocarbon solvent naphtha (also known as high Boiling point aromatic hydrocarbon solvents refer to aromatic hydrocarbon mixtures with more than 10 carbon atoms).
③Alcohols: including methanol, ethanol, isopropyl alcohol, n-butanol, benzyl alcohol, etc.
④Esters, alcohol esters : Ethyl acetate, butyl acetate, sec-butyl acetate, propylene glycol methyl ether acetate (PMA), propylene glycol ethyl ether acetate, ethylene glycol Diethyl ether acetate, ethylene glycol butyl ether acetate, dimethyl carbonate, mixed dibasic acid ester (DBE), mixed acid propylene glycol ester (CBE), polyol dibasic acid ester (EGDA), etc.
⑤Ketones: acetone, methyl ethyl ketone (butanone), cyclohexanone, methyl isobutyl ketone (MIBK), isophorone, diacetone alcohol, etc.
China's limit standards for harmful substances in coatings limit requirements for some solvents
Standard name | Restricted solvents | Limited value |
Limits of Hazardous Substances in Marine Coatings | Toluene (limited solvent coating | ≤15% |
Methanol (limited to inorganic coatings) | ≤1% | |
Sum of halogenated hydrocarbons | ≤1% | |
Benzene | ≤1% | |
The sum of glycol ethers and ether esters | ≤1% | |
Limits of Hazardous Substances in Indoor Floor Paints | Benzene | ≤0.1% (solvent and solvent-free) |
Sum of benzene, toluene, ethylbenzene and xylene | ≤20% (solvent type);≤1% (solvent-free) | |
The sum of glycol ethers and ether esters | ≤300mg/kg | |
GB 24409-2009 Limits of Hazardous Substances in Automobile Coatings | Benzene | ≤0.3% (Class A) |
Sum of benzene, toluene, ethylbenzene and xylene | ≤40% (Class A) | |
Glycol ether and the sum of ether esters | ≤0.03% (Class A, B) | |
GB 30981-2014 Limits of Hazardous Substances in Anticorrosive Coatings for Building Steel Structures | Benzene | ≤1% |
The sum of halogenated hydrocarbons | ≤1% | |
Methanol (limited to inorganic coatings) | ≤1% | |
Glycol ether sum | ≤1% | |
GB 24613- 2009 Limits of Hazardous Substances in Toy Paints | Benzene | ≤0.03% |
Sum of benzene, toluene, ethylbenzene and xylene | ≤20% |