A low-cost method of producing coated boxboard or coated kraft paperboard produced by the method and coated kraft cardboard or coated cardboard box

The invention relates to a coated box board or coated kraft liner, in particular to a coated box board/kraft liner and a method for producing the same at low cost. The method comprises the steps of coating prime coat on the box board or unbleached kraft liner and coating top coat on the box board or unbleached kraft liner, wherein the primer coat comprises starch; and the top coat comprises an optical brightening agent. The coated box board or coated kraft liner and the method have the following beneficial effects: the prime coat and the top coat do not have mandatory requirements for the rawmaterials and different quality of pigments can be used in the coat of different coatings, thus further saving the production cost, and the coating weight each time is lower, thus not only being beneficial to drying but also being beneficial to improvement of the production efficiency.