Corrugated board is produced by guiding a paper web, the corrugating medium or fluting, through a silt between two corrugated rolls and pressing it into a waveform through a conbiation of pressure and heat. In the same machine, a even paper web(facing or liner) is then glued on to this corrugated board on one or both sides. Illustrates the manufacturing of corrugated board Corrugated board is engineered for stackability. It withstands top and side pressure, and it is crush-resistant and passes brust-strength tests. Corrugated baord offers tear, tensile and burst strength to withstand shipping pressure. Corrugated board resists impact, drop and vibration damage and offers uniform stacking and weight distribution.
Corrugated board is mainly used to make containers for shipping products to factories, warehouses, retail stores, offices and homes. It is good to use corugated cardboard for transporting these products because it is light, strong and easily custom-sized for all products. Corrugated medium layered between inside and outside linerboard. On the production side, corrugated is a sub-category of the paperboard industry. On the marketing side, it is a part of the packaging industry.
Throughout the distribution cycle of moving goods from producer to consumer, corrugated boxes are the most widely used shipping containers. Traditionally, corrugated is best known for its structural stength that offers protection to packaged products throughout the transportation cycle. However, it has evolved over the course of time and today it is a much more versatile product.
According to the number of outer/inter mediate plies and flutes, corrugated board is classified as follows: single face corruaged board, single wall(double faced) corrugated board, twin wall corrugated board, triple wall corrugated board. below picture illustrates the types of corrugated board. Corrugated board is mainly made in one of four flute sizes, designated A, B, C and E. There are, however, other flute sizes available in the market which adapt the material to numerous usage.
A-flute is the original flute. Because of its highest flute size, A-flute provides excellent cushioning and stacking properties for fragile and delicate items.
B-flute has more flutes per meter and lower arch heights in the flute profile, therefore, it has a higher crush resistant property tahn A-flute.
C-flute is thinner than A-flute, thicker than B-flute, and provides good cushioning, stacking and printing properties. C-flute is by far the most widely used flute size.
E-flute has the greatest number of flutes, and therefore it provides the greatest crushing resistance and the flatest surface for high quality printing applications.
Generally, larger flutes provide greater strength and cushioning, while smaller flutes have better printability and foldability. Flute profiles can be mixed and matched within the same piece of combined board, to mainpulate printability, compression strength, cushioning strength and the total thickness of the board. For instance, CE double wall gets its durability from its C-flute layer, while the E-flute gives it a smoother printing surface.
In 1856, the first known corrogated material was patented for sweatband lining in top hats. During the following four decades other forms of corrugated material were used as packaging material for glass and other products shipped in wooden crates, Then in 1894 the first corrugated box was made.
At this point production of corrugated was very slow and the market was skeptical of its use as a dependable shipping material. Over the next several years it was only used to package lightweight items delivered locally. However, by 1990 there was a nationwide network of railroads which made it possible to distribute products thoughout the nation. At this point corrugated containers were still not a recognized classification by which to ship goods. The term”contained” meant enclosed on all sides in wood. Then in 1903 corrugated was approved as a valid shipping material for a manufacturer of cereal that had obtained an exception to the official classification.
This initial acceptance jump-started the market for corrugated production and by 1910 there were an estimated 50 companies in business making corrugated or solid fiber boxes. While corrugated lacked the stacking strength of wood it was more affordable, more readily available, lighter weight, more uniform in quality, and more adaptable to volume packing, sealing, and handling. It also offered cushioning and printability advantages. All of these characteristics were attractive to businessmen at that time who were eager to take advantage of nationwide distribution at that time who were eager to take advantage of nationwide distribution. Corrugated soon became the dominant shipping container and has adapted to and evolved with changing over the years to solidify and epand its role.
The corrugated industy has done a great job with recycling. In 2003, recovery of old corrugated containers rose to a record high of 75.2%. This is up almost 25% since 1997. Converters are also using more environmentally frindly inks in their printing processes. Legislation in the early 90’s reduced the allowable content of certain metals such as mercury, lead, cadmium, and copper. The corrugated industry had already reduced the levels of these metals. The use of oil based inks and clean up solvents that contain dangerous volatile organic compounds(VOC’s) has been virtually eliminated in corrugated plants. Water based inks are now used almost exclusively. The qulaity of the water discharged from box plants has improved significantly. Water quality is measured in terms of biological oxygen demand(BOD) and from 1984 to 1993 BOD was cut in half and has continued to improve. Some plants have zero discharge.