In this paper, we report on new polyphenols synthesized by the condensation compounds of phenols and aldehydes. The phenols were 4,4'-biphenol, 2,6-dihydroxynaphthalene and 2,7-dihydroxynaphthalene. The aldehydes were 4- phenylbenzaldehyde and 4,4'-biphenyldicarbaldehyde. And we evaluated basic properties for the Spin-On Carbon Hardmask . We recognized 4,4'-biphenol was showed good applicability to the best raw material of the phenols for polyphenol, and 2,6-dihydroxynaphthalene was showed good applicability to better raw material for polyphenol than 2,7-dihydroxynaphthalene. 4,4'-biphenyldicaraldehyde was better raw material of the aldehydes for polyphenols than 4- phenylbenzaldehyde, in solubility. As for heat resistance, 2,6-dihydroxynaphthalene was the best raw material of the phenols for polyphenols, 2,7-dihydroxynaphthalene was better raw material for polyphenols than 4,4'-biphenol. However, NF7177 synthesized by the condensation of 4,4’-biphenol and 4-phenylbenzaldehyde and NF7A78 synthesized by the condensation of 4,4'-biphenol and 4,4'-biphenyldicarbaldehyde seem to be crosslinking by heating, whence the heat resistance of the polyphenols using 4,4'-biphenol might be improved by optimizing heating condition. These materials are low molecular weight of less than 1000, so we expected having good planarization and gap filling.