NOVELTY - Producing reduced or partially reduced graphene oxide, involves: (a) providing graphene oxide; and (b) applying a reducing agent to at least part of the graphene oxide.    USE - For producing reduced or partially reduced graphene oxide, which is in the form of a circuit pattern, used as a conducting or partially conducting coating, an anti-microbial coating, an anti-corrosion coating, or an anti-static coating, in and device; or as a conductor for the electrical conduction of electricity (claimed); used in the production of electrodes, sensors, bionic devices, energy conversion devices, fuel cells, solar cells, water splitting cells, water cleaning cells, energy storage devices, rechargeable batteries, super capacitors, hybrid cells, electronic devices, display devices, electrochromic cells, communication/asset tracking devices, electrochemical devices and/or wearable devices; particularly sensors including variable conductivity/resistivity elements combined with functionality; biocompatible materials for biomimetic application; electronics including for e.g. printed circuitry, logic devices, components for anti-static devices; variety of functional coatings and composites for e.g. antifouling coatings for ships and marine structures or anti-radar coating applications; and metal free inductive devices and other solid state 3D conductive devices.    ADVANTAGE - The method provides a simple scalable and ecologically sustainable chemical process to create highly conducting (2000 S/cm), flexible, printable, processable reduced graphene oxide materials without the need for harsh chemical treatment or high temperature annealing. The method enables to produce reduced (rGO) or partially reduced (prGO) graphene oxide films that have improved conductivity when compared to rGO films prepared by other methods. The present method permits selective reduction of graphene Oxide (GO) films using an environmentally friendly and easily scalable process. Rather than chemically reducing GO in solution and subsequently applying the rGO to a surface, the present method reduces GO deposited on a substrate. With the present method, a GO film can be patterned or printed with reducing agent to produce highly conducting rGO tracks within a GO insulating matrix. The present method achieves conductivities of pure CVD grown graphene (3000 S/cm); and no need for high temperatures or post-treatment procedures. The present method can be carried out in room temperature conditions. This is an important factor in, for e.g. the electronics industry, as back-end chip technology requires procedure temperatures to be less than 300 degrees C. The method permits the use of environmentally and operator friendly reducing agents such as ascorbic acid.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a substrate having a layer of reduced or partially reduced graphene oxide on its surface, where the layer has a thickness of less than 2 mu m and a conductivity of greater than 1000 S/cm.