Inorganic fiber sizing agent and inorganic fibers
Disclosed is an inorganic fiber sizing agent that contains an epoxy compound, an aliphatic sulfonic acid salt, and a nonionic surfactant.
1 . An inorganic fiber sizing agent comprising an epoxy compound (A), an aliphatic sulfonic acid salt (B), and a nonionic surfactant (C), wherein taking the sum of the contents of the epoxy compound (A), the aliphatic sulfonic acid salt (B), and the nonionic surfactant (C) as 100 parts by mass, the inorganic fiber sizing agent contains the aliphatic sulfonic acid salt (B) at a content of greater than or equal to 0.01 parts by mass and less than or equal to 0.9 parts by mass, wherein the aliphatic sulfonic acid salt (B) is an aliphatic sulfonic acid alkali metal salt.
2 . The inorganic fiber sizing agent according to claim 1 , wherein the aliphatic sulfonic acid salt (B) includes an aliphatic sulfonic acid salt (B1) that has a primary sulfonic acid group and an aliphatic sulfonic acid salt (B2) that has a secondary sulfonic acid group.
3 . The inorganic fiber sizing agent according to claim 1 , wherein the nonionic surfactant (C) includes a nonionic surfactant (C1) that has a single ester bond and an ether bond in its molecule.