Iron powder for exothermic composition, production method therefor, exothermic composition using said iron powder, and exothermic body production method

Abstract

An iron powder for an exothermic composition according to the present invention has a bulk density of 0.3 to 1.5 g/cm3. Furthermore, an exothermic composition according to the present invention contains the iron powder, a carbon material, a halide salt, and water. Furthermore, an exothermic body production method according to the present invention includes: forming a coated member by coating a base material sheet with a flowable exothermic composition containing the iron powder, a carbon material, and water; and adjusting an amount of moisture in the coated member by removing water from the coated member. Furthermore, the present invention is directed to a production method for the iron powder (an iron powder for an exothermic composition) including: a reducing step of reducing iron oxide to obtain reduced iron; and a step of milling the reduced iron. In the reducing step, the iron oxide is reduced by introducing iron oxide and a solid reductant with a volatile matter content of 10% by mass or more into a heating furnace whose internal portion contains no sulfur gas or is set to an air or inert gas atmosphere, and setting the internal portion to a reducing gas atmosphere through heating under a condition that an ambient temperature of the internal portion is from 900 to 1000° C.

Dependencies are inferred from the claim text.