| abstract |
(57) [Summary] [Problem] A dimensional change is extremely small even in an atmosphere where high and low temperatures are repeated or in an atmosphere involving moisture absorption and desorption, and when used as a reinforcing fiber of a resin reinforced laminate, drilling or cutting is performed. An aromatic polyamide fiber and a fiber which can form a flat and clean processed surface, in which a fibrillation or a defective fiber cutting does not easily occur on the cut surface, the cut surface, and the laser processed surface when laser processing is performed; An aromatic polyamide fiber paper comprising: SOLUTION: From the diffraction intensity curve of wide angle X-ray diffraction, Scherr The apparent crystal size determined by the er equation is A fiber that simultaneously satisfies (3), and has a coefficient of linear thermal expansion of -1.0 × 10 −6 / ° C. to −7.5 × 1. This is achieved with aromatic polyamide fibers in the range of 0 -6 / ° C. (1) Crystal size (A) of 110 plane is 75 (angstrom) or more (2) Crystal size (B) of 200 plane is 82 (angstrom) or more (3) A × B is 6150 to 63000 |