White cardboard is used for printing business cards, envelopes, certificates, invitations and packaging and decorating cardboard, white cardboard for the flat paper, the size of the main: 880mm * 1230mm, 787mm * 1032mm. According to the quality level white cardboard is divided into A, B, C three.
Thick white cardboard firm, more quantitative, the quantitative 200 g / m2, 220 g / m2, 250 g / m2, 270 g / m2, 300 g / m2, 400 g / m2 and other specifications. White cardboard tightness is usually not less than 0.80 g / m3, whiteness requirements are higher, A, B, C third-class whiteness were not less than 92.0%, 87.0%, 82.0%. To prevent swill, white cardboard requires a greater degree of sizing, A, B, C and other three sizing degree of not less than 1.5mm, 1.5mm and 1.0mm. In order to maintain the smoothness of paper products, white cardboard should be thick and firm, high stiffness and bursting strength, for different grades of different quantitative white card its stiffness have different requirements, the larger the quantitative, the higher the level, very The greater the degree of requirement, the general longitudinal stiffness should not be less than 2.10-10.6mN • m, transverse stiffness should be not less than 1.06-5.30 mN • m.
A, B, C third-class burst resistance index of not less than 2.00KPa • m2 / g, 1.60 KPa • m2 / g and 1.20 KPa • m2 / g. In order to ensure the printing ink evenly distributed and the appearance of the paper itself, the smoothness of the white card is not less than 20-40S. In addition, white cardboard paper should be flat, not allowed to have spots and streaks and other paper diseases, warping deformation is not allowed, the paper should be uniform fibrous tissue, dust no more than 0.2-1.5mm2 28 / m2 (A, etc. ), No more than 1.5mm2 dust.
White cardboard is usually 100% bleached pulp as raw material, the surface, the bottom of kraft chemical softwood pulp, core hardwood chemical mechanical pulp, slurry after beating by adding calcium carbonate, barium sulfate and other fillers, with AKD for neutral heavy sizing, paper-making on a wire-net paper machine, calendering and coating, as required, after embossing to produce cardboard with special embossed pattern, Special embossed white cardboard may not check the smoothness and whiteness. In addition to white, through the pulp dyeing, but also produce a variety of color cardboard, then the whiteness, the other technical performance are consistent with the technical performance of white cardboard.