| 摘要 |
In the field of printed circuit boards and circuit boards, the present invention has excellent glass cloth impregnating abilities and prepreg appearance, and exhibits excellent heat resistance in a cured product thereof. The present invention provides a phosphorus atom-containing phenol resin which has a phosphorus atom-containing structural site (i) represented by structural formula (Y1) or (Y2) (In the structural formulas (Y1) and (Y2), R1 to R4 are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) and an alkoxymethyl group (ii) in an aromatic nucleus of a phenol compound, wherein the percentage of the number of the alkoxymethyl groups (ii) with respect to the total number of the phosphorus atom-containing structural sites (i) and the alkoxymethyl groups (ii) is 5 to 20%. |
