Abstract: A method for manufacturing a paper core material is described. The paper core material has uses such as in the building industry and has the advantage that no toxic home syndrome is caused in a newly built house or office. The paper core material has a continuous geometric pattern such as rectangular or hexagonal cells and is made by the method of providing a plurality of base paper strips, bending and gluing the base paper strips to form the paper core material having a continuous geometric pattern, treating the paper core material with a charcoal solvent comprising activated carbon dust, wood vinegar and a flame-resisting agent, and drying the paper core material. An alternate method is provided which involves treating the base paper strips with the charcoal solvent, drying the base paper strips, and then bending and gluing the base paper strips to form the paper core material having a continuous geometric pattern.