Ms Twinkle Parikh – Managing Partner – Sanjay Adhesives
Flute buckling refers to deformation of flute due to vertical stress on the corrugated fibreboard. Buckled flutes is one of the major factors that lead to a dramatic reduction in Compression Strength (C.S.) of the board. Hence one of the means to increase board’s C.S. without altering the manufacturing process is to limit this buckling mode. But the real challenge lies in reducing this subjected vertical stress on the board, given the area and transportation constraints.
Furthermore, these light weighted linerboards are subjected to high densification for scrimping and saving, given the tight budgets at all levels. So finding a cost effective and reliable solution is a prerequisite to be a successful quality optimizer.
One of the most efficient ways to optimize the quality and prevent flute buckling is with the use of right adhesive, which amounts to a minuscule change in raw material. Adhesive can excellently aid in remodelling the boards’ ECT, overall stiffness and Bending Stiffness. While the combination of papers chosen to build the corrugated fibreboard, flute pitch, flute height, arc radius and angle of wrapare critical factors, the adhesive and its application also plays a significant role in obtaining the best board at the end of the sophisticated machinery.
Adhesive prepared using Steins Halls Method is highly alkaline due to the use of caustic soda. Caustic Soda has great affinity for and absorbs moisture from the atmosphere. It is extremely hygroscopic and rapidly absorbs water and carbon dioxide from the atmosphere becoming wet and slimy. When thefibreboards prepared using this adhesive containing caustic soda is exposed to high humidity, it also tends to absorb more moisture than necessary which results in flute buckling due to vertical stress.
Today boxes are used for packing every imaginable product including machinery, electronics and perishables. The use of box is not just constricted as a means to just protect the product it holds but is also used as a medium of advertisement and information. Wet and soft corrugatedfibreboards can be a menace at any given juncture as printing quality suffer in such fibreboards.
Modified starch adhesives with low alkaline hydrogen ion concentration can outplay and deliver better strength and stiffness while accelerating the speeds of productions. Modification of starch involves processing the native starch to alter its physiochemical properties by various means to alter its stability, gelatinization temperature, hygroscopicityand adhesion strength. Modified starch adhesive can also help muddle through warpage resulting from superfluous dampness.
The right Adhesive bequeaths high quality bond and high productivity through the whole range of boards produced. It ensures that overall strength and performance of the board does not get affected by external environmental factors.
It is important to note that the structural strength of corrugated fibreboard stems from its fluting geometry. Correct corrugator setup to ensure glue application on centre is inevitable despite good paper and adhesive. If Bond Centering is not achieved, one side of the flute will be stronger and one will be weaker, which will negatively affect overall Compression Strength.
