| abstract |
An object of the present invention is to provide a production method capable of stably and efficiently performing a flame-resistant treatment even when fibers are present at a high density, and to provide a high-performance flame-resistant fiber and a carbon fiber. It's something you want. The oxidized fiber material of the present invention has an average oxygen concentration in the fiber of 0.07 to 0.17 measured by elemental analysis / oxygen analysis. The method for producing a flame-retardant fiber material of the present invention comprises the steps of converting an acrylic fiber material into an organic compound, excluding an amine compound, a fluorine compound, a siloxane, a nitrate, and a compound of one or more of two or more nitrites. It is characterized in that it is subjected to a flameproofing treatment at 300 ° C. The outermost surface measured value A1 of π * / σ * and the highest value A2 inside the single fiber obtained by measuring the cross section of the single fiber of the carbon fiber material of the present invention by electron energy loss spectroscopy using a field emission electron microscope. Is in the range of 0.83 to 0.94. [Selection diagram] None |