| 摘要 |
PURPOSE:To provide a highly sensitive photoset magnetic fluid which ensures highly sharp image sensing by adding a specific amount of photosetting resin to a magnetic fluid consisting of a dispersion medium of low viscosity, fine ferromagnetic particles and a surface active agent. CONSTITUTION:In the magnetic fluid consisting of a dispersion medium of low viscosity, ferromagnetic fine particles and a surface active agent which disperses stably such fine ferromagnetic particles in the dispersion medium, photoset resin of at least 25 vol.% is mixed with the dispersion medium. On the occasion of using the photoset magnetic fluid for magnetic flaw detection and visualization of magnetic recording pattern, the surface of sample forming a magnetic field is first coated with the fluid. Hence, the magnetic fluid is attracted to form a mound depending on the leakage magnetic flux of defective part of sample and change of magnetic flux density of magnetic recording. Thereafter, the coated film is irradiated with the light having the wavelength enough for setting the photoset region in the magnetic fluid. Accordingly, a pattern of magnetic fluid can be fixed and minor defect and magnetic recording pattern can be observed more clearly. |
