Metal-clad phenolic resin laminate

A metal-clad phenolic resin laminate obtained by heating and pressing a lamination which comprises:

• (i) a central portion comprising one or a plurality of paper base prepregs, each of which is made of a paper base impregnated with a first phenolic resin composition, wherein said paper base is selected from the group consisting of kraft paper, linter paper, pretreated kraft paper with a water-soluble phenolic resin or a methylol melamine resin, and pretreated linter paper with a water-soluble phenolic resin or a methylol melamine resin;
• (ii) outer portions laid on upper and lower sides of the central portion, in which each of the outer portions comprises one or a plurality of glass fiber substrate prepregs, each of which is made of a glass fiber substrate impregnated with a second phenolic resin composition;
• and
• (iii) a metal foil laid on one or both of the outer portions;
• wherein each of the first phenolic resin composition and the second phenolic resin composition contains an unmodified resol-based phenolic resin, a novolac-based phenolic resin, an oil-modified resol-based phenolic resin, and one or more flame-retardant compounds selected from the group consisting of a halogen compound, a phosphorous compound and an amino resin,
• a total amount of the unmodified resol-based phenolic resin and the oil-modified resol-based phenolic resin is 30 to 60 wt %, an amount of the novolac-based phenolic resin is 5 to 20 wt %, and an amount of the oil-modified resol-based phenolic resin is 10 to 40 wt %, with respect to the total amount (based on solid content) of the phenolic resin composition,
• an amount of the flame-retardant compound is 5 to 36 wt % with respect to the total amount (based on solid content) of the phenolic resin composition, and
• a long-term moisture absorption rate of said central and outer portions after the metal foil is removed from the metal-clad phenolic resin laminate in accordance with JIS C6481, and being left under an environment of 60° C. and 90% relative humidity for 1,000 hours and left under an environment of 20° C. and 65% for 30 minutes, is 2 wt % or less.