| 摘要 |
PROBLEM TO BE SOLVED: To provide a resinoid grindstone, which is especially useful in heavy-duty grinding applications, excellent in heat resistance as a problem of the conventional resinoid grindstone, and excellent in durability, and to provide a phenol resin composition from which the resinoid grindstone can be produced.SOLUTION: A resinoid grindstone is obtained by using a phenol resin composition obtained by blending a phenol resin/boric acid compound mixture, which is obtained by adding boron oxide to a reaction product obtained when an addition condensation reaction of phenols with formaldehydes is completed and heating/dehydrating the boron oxide-added reaction product under reduced pressure. The phenol resin composition is used for producing the resinoid grindstone. |
