Production method of film paperboard

The invention discloses a production method of film card paper. The method comprises the following steps: A, detecting the content of metal ions such as iron ions and calcium ions in slurry and production water, and making sheets in a laboratory; and b, taking the selected primary pulp, smashing with production water, adding salt substances of ethylenediamine tetraacetic acid during pulp grinding and pulp mixing, obtaining paper pulp needed by papermaking through a slag removal system, diluting the prepared pulp with production water to the concentration required by quantification of each layer, feeding into a paper machine, dehydrating and forming through each layer of forming net, spraying an interlayer bonding auxiliary agent, and carrying out compounding, squeezing, steam drying, surface treatment and coiling on all the layers of wet paper sheets to prepare finished paper. According to the invention, the method has the advantages that the number of the metal iron points is far less than 4000/m ; and durin