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Adhesive tape was invented in 1925. As a painter's masking tape for auto body shops. That lead
to transparent tape designed to seal the cellophane wrap by the food industry. Then tape was introduced
as a household item and the idea just stuck. These rolls of plastic film called polypropylene
are on their way to becoming shipping tape. The rolls go on a machine called the "Unwinder".
Workers then position a strip of adhesive splicing tape along the end of each roll.
This will enable them to connect one roll after another. Creating an uninterrupted feed
to the production line. Now watch closely. Once a roll unwinds completely
it's end sticks completely onto the end of the next roll.
Once that roll is unwind it's end will stick to the beginning of the next, and so on.
An automatic tension adjuster ensures that the machine pulls the film evenly to prevent
ripping. The "Unwinder" also applies a solvent to the
films surface. This prevents the film from sticking while unrolling.
To transform this film into tape, they coat one side with a hot adhesive, known as "hot
melt". Made from several ingredients. Synthetic rubber gives it flexibility.
A UV protector keeps it from drying and discoloring. While an antioxidant prevents aging.
Synthetic resin makes it sticky. While pigmentation oil provides a choice of
colors. In this case, tan.
They load the "hot melt" into a preheated holding tank which maintains it at a pipping
200 degrees Celsius, to keep it from hardening. The tank pumps the adhesive through to a machine
called the "Gluer". They wipe away the excess.
Then roll the film.
And there goes the adhesive. A cooling roller. That black one on the top.
Immediately hardens it. A computerized sensor ensures there is an
even coat of adhesive. If not it automatically signals the pump to adjust the output.
Now a machine, called the "Rewinder", rolls the tape onto spools.
Remember the "Unwinder" that spliced the rolls together? Well, the "rewinder" unsplices them.
When a spool fills, a knife separates the tape at the splice point. So that winding
can begin on the next spool.
The tape on just one of these spools would run the length of 85 football fields.
The spools feed a roll of sharp razor blades called the slitters. Which divide the meter
and half wide tape into several strips. Shipping tape is 48 millimeters wide. So, they get
31 strips per spool. Each strip winds onto a cardboard core. It's
ends sealed with a tab.
The length of tape per roll varies according to the customer's specifications.
As the machine ejects the finished tape rolls. In comes the next batch of cardboard cores.
Then it is off to the packing department. Nothing is shipped out however before a quality
control check. They test a sample roll of each spool.
In one test they unwind the tape sticky side up, then release a tiny stainless steel ball
down the incline. Measuring how far the ball rolls before it sticks and comes to a stop.
to pass the test the ball has to adhere within a certain distance.
The stopping distance varies depending on the type of adhesive tape.