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Flip Flop Day!

We’ve had a very hot week, so it’s fitting that it is National Flip Flop Day! Celebrated the third Friday in June, National Flip Flop Day was created by the restaurant Tropical Smoothie Cafe as a fundraiser for Camp Sunshine, a summer camp for children with life-threatening illnesses. 

Flip flops became popular in America after World War II when American soldiers brought Japanese zori back from their deployments. Zori can be traced back to the Heian Period (794-1192 CE) and are often paired with tabi socks, which allow the wearer to don both socks and sandals at the same time. Today Americans often wear their flip flops during summer activities like going to the beach, so we forego the socks. 

Traditional Japanese Zori Men's Sandals in Straw Velvet | Etsy Singapore
Traditional Japanese Zori

Flip flops are not patented, but improvements to them can be patented! How would you improve your flip flops?

Many patents are for decorative elements and the ways in which they are attached to the shoe, like this daisy or this fun fringe

Replaceable Ornament for Flip-Flop Sandal, US 2010/00116223 A1


Flip-Flop Shoe and Method of Making Same US 2006/2013080 A1

Some people seek to improve the functionality of flip flops, like adding straps or creating a convertible flipflop/slipper.

Flip-Flop Back Strap Device US 8381415 B1
Flip Flop and Slipper in One/Convertible Sandal Slipper US 2012 0079739 A1

If you want a more scientific approach to flip flops and shoes in general, come check out The Science of Footwear edited by Ravindra S. Goonetilleke to learn more about everything in the process of designing, manufacturing, and marketing footwear.


Stay cool and wear your flip flops to the beach this weekend!