Zipper storage bag
A zipper storage bag or slider storage bag is an inexpensive flexible rectangular storage bag, usually mainly transparent, made of PVC or similar plastic, which can be sealed and opened many times by a slider which works in a similar way to a zip fastener. The bags are made in many sizes; a typical small size is 1.5 by 2.5 inches (3.8 cm × 6.4 cm) suitable for a few buttons, a large size is 9 by 12 inches (23 cm × 30 cm). Material thickness (gauge) varies; smaller bags are typically 40 to 45 µm.
Many such bags are of food grade, suitable for foodstuffs such as sandwiches, and freezer storage. Single and multiple small items for sale are often packed in small zipper bags for convenience and visibility.
Sometimes other types of bag, such as a cloth bag for toiletries fitted with a conventional zip fastener, are described as zipper bags.
The bag was patented by Robert W. Vergobbi on May 18, 1954. In the same year, Minigrip licensed them as pencil bags. The zipper storage bag's most recognized function was not realized until 1957, when a fifth-grader named Robert Lejeune demonstrated that the bag could also be used safely as a food storage device.  Eleven years later, in 1968, Dow Chemical Company began marketing them under the name Ziploc.
- Yam, Kit L (2009). The Wiley Encyclopedia of Packaging Technology. John Wiley & Sons. ISBN 978-0-470-08704-6.