Abstract: The invention has been achieved to solve the problem mentioned above. The object of the invention is to provide a novel method of manufacturing a printed wiring board by allowing manufacturers to provide a slit and perforations on the substrate without causing even the slightest crack to be generated in the course of manufacturing the printed wiring board.In the course of manufacturing printed wiring boards splittable across a slit and perforations,the method embodied by the invention executes those sequential steps including the following; provision of thickness adjusting film for specific regions adjacent to the slit and perforations; adjustment of the thickness of a main substrate and a splittable substrate which is splittable by means of the slit and the perforations; and formation of the slit and the perforations by applying a pressing and punching process.

Abstract: The invention relates to a biological activator for septic tanks. The biological activator is characterized by the fact it is in the form of a non-corrosive, non-toxic, finely-divided product having a significant specific surface constituting a base for the optional anaerobic microbic flora, permitting an increase in the density of bacterial saturation in the septic tank for an equivalent quantity of nutriment.