A novel process and intermediates thereof for making 4,5-dihydro-pyrazolo3,4-cpyrid-2-ones of the type shown below from appropriate phenyl hydrazines is described. The summing device is coupled to an output node. The OS storing unit includes a first region that stores an OS and a second region that stores a check value of an algorithm, the check value corresponding to the OS. Then, operation of reading out photographing data from the memory and performing digital development processing again is executed a necessary number of times. The invention furthermore relates to a heating device to be used in a device for the evaporation of volatile active substances as well as to a method for the production of the heating device.