Corrugated cardboard, also known as corrugated cardboard. It is made of at least one layer of corrugated paper and one layer of carton paper (also called carton board), which has good elasticity and extensibility. Mainly used in the manufacture of cartons, carton sandwiches and other packaging materials for fragile goods.
Also known as corrugated cardboard. It is made of at least one layer of corrugated paper and one layer of carton paper (also called carton board), which has good elasticity and extensibility. Mainly used in the manufacture of cartons, carton sandwiches and other packaging materials for fragile goods. Soil straw pulp and waste paper were beaten to make yellow cardboard-like base cardboard, then machined to roll into corrugated shape, and then bonded with box paper with sodium silicate and other adhesives on its surface.
Corrugated corrugates of corrugated cardboard are like connected arched doors, which are arranged side by side and support each other to form a triangular structure. They have good mechanical strength, can withstand certain pressure from the plane, and are elastic and have good cushioning effect. They can be made into cushions or containers of various shapes and sizes according to need. It is simpler and faster than plastic cushioning material, less affected by temperature, better shading, no deterioration by light, and generally less affected by humidity, but it is not suitable for long-term use in humid environment, which will affect its strength.
Classification:
According to different combinations, corrugated cardboard can be divided into the following five types:
1. The cardboard consisting of a layer of core paper and kraft cards is called "dew corrugated cardboard". Corrugated cardboard is generally used only as cushion, spacer and wrapping irregular objects.
2. The cardboard consisting of a layer of core paper and two layers of kraft cards is called "single pit cardboard".
Corrugated cardboard:
3. Two layers of core paper are divided into three layers of kraft cards called "double pit cardboard". Double pit cardboard can be made up of pit paper with different pit width and paper quality, such as "B" pit paper with "C" pit paper.
4. Three-layer core paper is called "three-pit cardboard" which is sandwiched in four-layer kraft cards.
5. Super-strong duplex cardboard is developed from single pit cardboard. Its middle layer of core paper is made of two pieces of thick core paper overlapped and bonded.
It is gratifying that today we have been able to produce many different combinations of corrugated cardboard, which have different characteristics and strength to meet the changing needs of the market.
Pit pattern:
Corrugated cardboard can be further subdivided according to the size of pits on core paper, i.e. its height and the number of pits per unit length. Core paper pit pattern
There are four kinds. The following table shows cardboard produced by Mitsubishi and Langston pit machines.
Compared with "B" and "C", cartons with thicker "A" pits have better top and bottom compressive strength, but with "A" and "B" pits, thinner "B" pits have better compressive strength. "A" and "C" pits are used in the manufacture of cartons under pressure and with pads for packaging. "B" pit pattern is suitable for the manufacture of cartons whose capacity and space are more important and whose stacking strength is less important. "E" pit pattern has the highest compressive resistance, but its shock absorption capacity is slightly poor. It is mainly used on offset (color printing) corrugated cardboard boxes with heavy loads.
Core material:
The bigger the pit diameter of corrugated cardboard, the stronger its rigidity. The toughness of cardboard originates from the core paper layer, without the need for thick and hard fillers. In this way, the weight and cost of cardboard can be reduced. Core paper can be made from semi-chemical pulp (which provides the best paper strength) and recycled paper. The latter is preferred by Hong Kong manufacturers because of its low cost. Although the paper strength is not as good as the former, it can be improved by adding starch to the paper mill.
The pits occupy a certain space in the corrugated paper, and play a very important role, by which they can withstand flat pressure, side pressure and other irregular pressures.
Leather card:
Kraft cards form the inner and outer layers of corrugated cardboard. Their functions may be structural and/or decorative. Each layer of kraft cards provides a variety of characteristics for cardboard, which can be expanded by bonding, waxing and other processing processes.
