The invention relates to a composition for the immediate termination of a free-radical polymerization, the use thereof for the stabilization of free-radically polymerizable monomers against free-radical polymerization and a method for the immediate termination of free-radical polymerizations.

The invention relates to a composition for the immediate termination of a free-radical polymerization, the use thereof for the stabilization of free-radically polymerizable monomers against free-radical polymerization and a method for the immediate termination of free-radical polymerizations.

A novel process can be used for purifying methyl methacrylate (MMA) contaminated with low-boiling components by distillation, where the process involves producing MMA by oxidative esterification, and a crude product containing methyl propionate (MP), methyl isobutyrate (MIB), and methacrolein (MAL) as low-boiling components. The process is compatible with MMA produced from C.sub.2-based methacrolein containing the low-boiling components specified.

A novel process can be used for purifying methyl methacrylate (MMA) contaminated with low-boiling components by distillation, where the process involves producing MMA by oxidative esterification, and a crude product containing methyl propionate (MP), methyl isobutyrate (MIB), and methacrolein (MAL) as low-boiling components. The process is compatible with MMA produced from C.sub.2-based methacrolein containing the low-boiling components specified.

An object of the present invention is to provide a chemical liquid purification method which makes it possible to obtain a chemical liquid having excellent defect inhibition performance. Another object of the present invention is to provide a chemical liquid. The chemical liquid purification method according to an embodiment of the present invention is a chemical liquid purification method including obtaining a chemical liquid by purifying a substance to be purified containing an organic solvent, in which a content of the stabilizer in the substance to be purified with respect to the total mass of the substance to be purified is equal to or greater than 0.1 mass ppm and less than 100 mass ppm.

Provided is a method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester (AGAECE) for photoresist processing, wherein the method comprises the step of distillation after passing industrial AGAECE through a porous adsorbent impregnated with a basic material, and it is possible to obtain a semiconductor-grade high-purity AGAECE maintaining a low acid value and high purity according to the present invention.

Provided is a method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester (AGAECE) for photoresist processing, wherein the method comprises the step of distillation after passing industrial AGAECE through a porous adsorbent impregnated with a basic material, and it is possible to obtain a semiconductor-grade high-purity AGAECE maintaining a low acid value and high purity according to the present invention.

An object of the present invention is to provide a chemical liquid purification method which makes it possible to obtain a chemical liquid having excellent defect inhibition performance. Another object of the present invention is to provide a chemical liquid. The chemical liquid purification method according to an embodiment of the present invention is a chemical liquid purification method including obtaining a chemical liquid by purifying a substance to be purified containing an organic solvent, in which a content of the stabilizer in the substance to be purified with respect to the total mass of the substance to be purified is equal to or greater than 0.1 mass ppm and less than 100 mass ppm.

The present invention is directed to a purification method for purifying a fluorine-containing polymerizable monomer of the formula (1), in which the fluorine-containing polymerizable monomer is purified by distillation in the coexistence of a phenolic compound A such as 6-tert-butyl-2,4-xylenol and a phenolic compound B such as 2,2′-methylene-bis(4-methyl-6-tert-butylphenol). ##STR00001##
By the combined use of the phenolic compound A and the phenolic compound B, it is possible to significantly suppress polymerization or oligomerization of the fluorine-containing polymerizable monomer even during industrial-production-scale distillation and efficiently purify the fluorine-containing polymerizable monomer by distillation.

The present invention is directed to a purification method for purifying a fluorine-containing polymerizable monomer of the formula (1), in which the fluorine-containing polymerizable monomer is purified by distillation in the coexistence of a phenolic compound A such as 6-tert-butyl-2,4-xylenol and a phenolic compound B such as 2,2′-methylene-bis(4-methyl-6-tert-butylphenol). ##STR00001##
By the combined use of the phenolic compound A and the phenolic compound B, it is possible to significantly suppress polymerization or oligomerization of the fluorine-containing polymerizable monomer even during industrial-production-scale distillation and efficiently purify the fluorine-containing polymerizable monomer by distillation.