Effect of paper`s grain direction on packaging design

　　Generally, the grain direction should be vertical with the main creasing line (longest creasing line).

　　Advantages：
•It makes the 4 surfaces of the box body smooth, avoid ballooning phenomenon.
•It is helpful to high speed automatic box-pasting machine.
•The creasing line is not easy to burst and break(especially on thick paper ).

　　When the carton size is small and accuracy requirement is not too high, it could apply mixed step- and-repeat ignore the grain direction, thereby saving cost.

　　The grain direction of Tubes with curved surface

　　The bending resistance of the paper`s vertical direction (perpendicular to the grain direction) is smaller than grain direction, which means it is more easily bent, so with the curved surface, the grain direction of the carton should be perpendicular to the curved creasing line.

　　We can clearly see the paper`s vertical direction is easy to bend so that the box body is formed into a very smooth arch. At the same time, box b on the contrary, because the unreasonable design caused the box body distortion.