| 摘要 |
PURPOSE:To produce a taken-up roll which is good after cutting without generating a beadlike build-up by irradiating the film with a laser of a specific wavelength, thereby cutting the film. CONSTITUTION:The film is cut by the irradiation with the laser having <=3600nm wavelength in the method for cutting the continuously transported film during the transportation. The light energy of this region exactly coincides with the region of the chemical bond energy of an org. compd. and, therefore, the absorption efficiency of the energy is extremely good and the energy is consumed only for cutting of the molecular bonds constituting the film. Then, the molecules of only the parts irradiated with the laser are cut and the conversion to thermal energy hardly changes regardless of the kinds of polymers and, therefore, the temp. rise of the peripheral part is small and the influence in the parts not irradiated with the laser beam is substantially eliminated. Then, the building up of the cut parts is obviated and the extremely sharp cut surface is obtd. |
