What does the colored block at the end of a toothpaste tube really mean?

What is the real story behind this information? Allegedly there are group of they (the name of the group or organization is unknown) try to explain to us who do not understand the meaning of the colored block on toothpaste. In fact they would like to shows us if the toothpaste is made entirely healthful products.

So what is the meaning of the colorful blocks:

• Red blocks are natural ingredients with some chemicals
• Blue blocks are natural ingredients plus some medicine
• Black blocks are all chemicals
• Green block are all natural

The most preferable are the pastes with green blocks.
In no incarnation of this myth does anyone try to explain who came up with this system of marking the tubes, nor do they explain why anyone would need to implement such a system.

But what is the real matter? These marks known as eye marks, color marks or printer marks are used as indicator to high-speed light beam sensors. They show where the tube should be cut or fold or sealed. This is almost too fast for the human eye to understand because the machinery works on the procedure that the change of color activates the sealing and cutting or folding mechanism.

According to another scientific discovery these marks are placed to line up the various colors on the tube. The marks are used to line up the three or four print runs so that the logos and images are lined up properly.