There are three ways toothpaste is striped.
The easiest way is to pour each color evenly into the tube, like this:
If you've ever seen striped taffy being made, it starts out as a series of large colored blocks which are extruded, creating thin, evenly colored pieces. The same principle works with toothpaste: The cone shape near the top forces the colors together evenly, creating an even mix of colors as the paste leaves the tube. However, if you push on one side, it's possible you could get just one or two colors to come out.
The second way is by using an internal valve. The main color fills the back of the tube, while the stripe color is near the opening. The opening is connected to a tube with holes around the stripe area and the paste area. Pressure on the tube draws paste from both sections. Invented in 1955 by Leonard Marraffino, he sold his patent to Unilever, who released the first striped toothpaste in 1960 under the name "Stripe."
The third way is done by dividing the paste into individual chambers that are mixed at the opening. This is only done with pump containers.
Posted 3944 day ago