A monomer has the structure

##STR00001##

wherein R is an organic group comprising a polymerizable carbon-carbon double bond or carbon-carbon triple bond; X and Y are independently at each occurrence hydrogen or a non-hydrogen substituent; EWG1 and EWG2 are independently at each occurrence an electron-withdrawing group; p is 0, 1, 2, 3, or 4; n is 1, 2, 3, or 4; and M.sup.+ is an organic cation. A polymer prepared from monomer is useful as a component of a photoresist composition.

Disclosed are a salt represented by formula (I), and a method for producing the salt, and a quencher and a resist composition comprising the same: ##STR00001## wherein R.sup.1 and R.sup.2 each represent a hydrocarbon group, and —CH.sub.2— included in the hydrocarbon group may be replaced by —O— or —CO—; R.sup.3, R.sup.4 and R.sup.5 each represent a halogen atom, an alkyl fluoride group or a hydrocarbon group, and —CH.sub.2— included in the hydrocarbon group may be replaced by —O— or —CO—; m3 represents an integer of 0 to 2, and when m3 is 2, two R.sup.3 may be the same or different from each other; and m4 and m5 represent an integer of 0 to 5, and when m4 and/or m5 is/are 2 or more, a plurality of R.sup.4 and/or a plurality of R.sup.5 may be the same or different from each other.

The present invention provides a sulfonium salt photoinitiator, a preparation method therefor, a photocurable composition comprising sulfonium salt photoinitiator, and use thereof. The sulfonium salt photoinitiator has a structure represented by formula (I). By modifying the structure of an existing sulfonium salt photoinitiator, a sulfonium salt photoinitiator having a new structure is obtained, which can exhibits a higher photosensitivity and an excellent as well as characteristics of low odor and low toxicity, when being used in a photocurable composition. This is significantly superior to existing similar photoinitiators. ##STR00001##

The present invention provides a sulfonium salt photoinitiator, a preparation method therefor, a photocurable composition comprising sulfonium salt photoinitiator, and use thereof. The sulfonium salt photoinitiator has a structure represented by formula (I). By modifying the structure of an existing sulfonium salt photoinitiator, a sulfonium salt photoinitiator having a new structure is obtained, which can exhibits a higher photosensitivity and an excellent as well as characteristics of low odor and low toxicity, when being used in a photocurable composition. This is significantly superior to existing similar photoinitiators. ##STR00001##

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

Provided are: a new sulfonium salt highly photosensitive to active energy ray, in particular, i-line or h-line; and a new photoacid generator which is highly photosensitive to i-line or h-line, and comprises a sulfonium salt that is highly soluble in a solvent and a cationically polymerizable compound such as an epoxy compound, and has excellent storage stability in the formulation. The present invention pertains to a sulfonium salt represented by general formula (1), and a photoacid generator comprising said sulfonium salt.

##STR00001##

Provided are: a new sulfonium salt highly photosensitive to active energy ray, in particular, i-line or h-line; and a new photoacid generator which is highly photosensitive to i-line or h-line, and comprises a sulfonium salt that is highly soluble in a solvent and a cationically polymerizable compound such as an epoxy compound, and has excellent storage stability in the formulation. The present invention pertains to a sulfonium salt represented by general formula (1), and a photoacid generator comprising said sulfonium salt.

##STR00001##

A monomer has the structure ##STR00001##
wherein R is an organic group comprising a polymerizable carbon-carbon double bond or carbon-carbon triple bond; X and Y are independently at each occurrence hydrogen or a non-hydrogen substituent; EWG1 and EWG2 are independently at each occurrence an electron-withdrawing group; p is 0, 1, 2, 3, or 4; n is 1, 2, 3, or 4; and M.sup.+ is an organic cation. A polymer prepared from monomer is useful as a component of a photoresist composition.

A monomer has the structure ##STR00001##
wherein R is an organic group comprising a polymerizable carbon-carbon double bond or carbon-carbon triple bond; X and Y are independently at each occurrence hydrogen or a non-hydrogen substituent; EWG1 and EWG2 are independently at each occurrence an electron-withdrawing group; p is 0, 1, 2, 3, or 4; n is 1, 2, 3, or 4; and M.sup.+ is an organic cation. A polymer prepared from monomer is useful as a component of a photoresist composition.