| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject precursor, from which a novolak resin suitable as a resinous component of a positive type photoresist composition can be synthesized by forming an ortho-ortho bond of a dihydric phenolic compound with a methylene group at a high rate. SOLUTION: This precursor is a connected body of phenolic compounds obtained by substituting one of H in the o-position or the p-position of the hydroxyl of a phenolic compound with a 1-3C alkyl or an alkenyl and connecting remaining two with a methylene bond. The percentage of the ortho-ortho bond based on the number of total methylene bonds in the entire connected body is 30-70%, and the weight average molecular weight of the precursor is 300-10000. The novolak resin is obtained by condensing this precursor with a trihydric phenolic compound in the presence of aldehydes. As a result, the generation of scum is suppressed without containing so much binuclear body and a positive type photoresist excellent in resolution, coating properties, etc., can be provided. |
