在如今很多行业都需要使用纸箱，但是如果是硬度不好的话，用纸箱装盛比较的物品就会很容易出现变形或者严重损坏。那么应该如何增强纸箱的硬度呢？
Nowadays, many industries need to use cartons, but if the hardness is not good, the articles packed in cartons will be easily deformed or seriously damaged. So how to enhance the hardness of cartons?
1、添加剂
1. Additive
这种方法就是在造纸前和造纸后向中添加各种化学晶，用于提高的粘结力，从而提高瓦楞纸箱的抗压强度。这些添加剂包括如玉米、淀粉、胶、粘合剂和重金属，及塑料和脲（甲）醛树脂。有时，也采用化学品喷涂纸箱外层的方法来加强纸板。
This method is to add various chemical crystals before and after papermaking to improve the adhesion of corrugated boxes, so as to improve the compressive strength of corrugated boxes. These additives include corn, starch, gum, adhesives and heavy metals, as well as plastics and urea formaldehyde resins. Sometimes, chemicals are also used to spray the outer layer of the carton to strengthen the cardboard.
2、高压
2. High pressure
高压纸板成形法也是一种在造纸过程中增强纸板强度的方法。采用扩大纸上的受压点来紧密地压缩纸板。而纸板结构越紧密，强度就越大。高压纸板成形也有助于从纸浆中挤出更多的水分，但是关键是要制成更紧密的纸板，提高其抗压强度。
High pressure paperboard forming is also a method to enhance the strength of paperboard in the papermaking process. Expand the compression point on the paper to compress the paperboard tightly. The tighter the paperboard structure, the greater the strength. High pressure paperboard forming also helps to squeeze more water from the pulp, but the key is to make a tighter paperboard and improve its compressive strength.
3、交联
3. Crosslinking
交联是一种在造纸过程中改变方向的加工方法。通常纸是纵向平行走向的，这种箱子成型后水平方向围绕在箱子周围，而这是造成纸箱抵抗压力的的坏方向。交联则使许多与机器方向呈90度走向，加工结果是许多与箱边上下垂直走向，这样就能不增加而增加了纸箱堆码强度。
Crosslinking is a processing method that changes direction in the papermaking process. Usually, the paper runs parallel in the longitudinal direction. After the box is formed, the horizontal direction surrounds the box, which is the bad direction that causes the carton to resist pressure. The cross-linking makes many 90 degrees to the direction of the machine, and the processing result is that many are perpendicular to the top and bottom of the box edge, so that the stacking strength of cartons can be increased without increasing.
4、层合
4. Lamination
这种增强瓦楞纸箱强度的方法是建立在两层或更多层；芯纸层合的基础上的。粘合剂可以是一种简单的玉米淀粉粘合剂，产生一种强度的芯纸以夹在交联的、加压成形的或常规强度的纸中间。
This method of enhancing the strength of corrugated boxes is based on two or more layers; Based on core paper lamination. The adhesive can be a simple corn starch adhesive that produces a strong core paper to be sandwiched between cross-linked, pressure formed or conventional strength paper.
