ALEXANDRIA, Va., Nov. 6 -- United States Patent no. 12,461,444, issued on Nov. 4, was assigned to SAN-APRO LTD. (Kyoto, Japan).
"Sulfonium salt, photoacid generator, curable composition, and resist composition" was invented by Takuto Nakao (Kyoto, Japan) and Yuji Nakamura (Kyoto, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "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 formulatio...