▎ 摘　　要

NOVELTY - Method for producing a flexible circuit board with an electric heating patch involves (a) adding the flexible single-sided copper-clad laminate and make a circuit pattern, (b) making a first solder resist ink composite graphene resin layer on the positive and negative combined circuits to form a resin layer flexible board, (c) adding a heat-resistant insulating sheet, the heat-resistant insulating sheet is a mica sheet or a glass fiber sheet, and make a second solder resist ink composite graphene resin layer on the heat-resistant insulating sheet, pre-baking, and cutting, forming several electrothermal patches with multiple sizes matching the size of a single positive and negative combined circuit, (d) carrying out alignment bonding, fast pressing, and curing and baking to form a circuit board to be attached, (e) attaching a cover film to the side of the circuit board to be attached with the electric heating patch, and performing post-processing to form the flexible circuit board. USE - Method for manufacturing a flexible circuit board with an electric heating patch for a heating device i.e. household water heater. Can also be used for an underfloor heating system. ADVANTAGE - The method provides flexible circuit board with high reliability, high heating efficiency, heating and cooling speed of the self-heating flexible assembly, and stable and reliable material performance. DETAILED DESCRIPTION - Method for producing a flexible circuit board with an electric heating patch involves (a) adding the flexible single-sided copper-clad laminate and make a circuit pattern, where the circuit pattern comprises positive and negative electrode combination circuits, (b) making a first solder resist ink composite graphene resin layer on the positive and negative combined circuits to form a resin layer flexible board, (c) adding a heat-resistant insulating sheet, the heat-resistant insulating sheet is a mica sheet or a glass fiber sheet, and make a second solder resist ink composite graphene resin layer on the heat-resistant insulating sheet, pre-baking, and cutting, forming several electrothermal patches with multiple sizes matching the size of a single positive and negative combined circuit, (d) where the side of the first solder resist ink composite graphene resin layer of the resin layer flexible board is opposite to the side of the second solder resist ink composite graphene resin layer of the electrothermal patch, carrying out alignment bonding, fast pressing, and curing and baking to form a circuit board to be attached, (e) attaching a cover film to the side of the circuit board to be attached with the electric heating patch, and performing post-processing to form the flexible circuit board, where the solder resist ink composite graphene resin are obtained by (i) adding the reduced graphene oxide, coupling agent and grafting agent, mixing to form a mixture, adding an acetone solution to the mixture for the first stirring, and obtaining the first component, where the weight ratio of the reduced graphene oxide to the coupling agent to the grafting agent is 7:1:1-5:0.5:0.5, and the weight ratio of the mixture to the acetone is 1:10-1:100, (ii) adding the first component into the solder resist ink, adding a dispersant, and performing a second stirring to form a second component, the weight ratio of the first component to the dispersant to the solder resist ink is 0.5:0.02:100-5:0.5:100, and (iii) adding an ink diluent to the second component, and performing a third stirring to form the solder resist ink composite graphene resin.