The Complete Handbook of Drink Sleeves

Chapter 1: Understanding Drink Sleeves

A drink sleeve is a removable covering that fits around the outside of a cup, can, or bottle to insulate the hand from the contents and to improve grip. You have handled thousands of them, but the engineering that makes a sleeve work is rarely examined. In its most common form - the corrugated paper sleeve found on hot coffee cups - the sleeve performs three jobs simultaneously: it reduces heat transfer to your hand, it prevents condensation on cold drinks from creating a slippery surface, and it provides a flat, printable area for branding. Each of those functions has design constraints that interact with the cup's geometry, the beverage's temperature, and the user's grip.

Consider the standard scenario at a coffee shop. The barista pulls a shot, steams milk, and assembles the drink in a 12-ounce paper cup. The cup is double-walled in some designs, but for a single-wall paper cup, the liquid inside is at roughly 80°C. A bare paper cup of standard weight conducts heat quickly; within fifteen seconds, the outer surface is uncomfortable to hold. The sleeve, made of corrugated board, creates a layer of trapped air between the cup wall and the sleeve's outer surface. Air is a poor conductor of heat. The corrugation - the fluted, wavy middle layer - holds that air in place and prevents it from circulating and carrying heat away from the cup. The result is that the outer surface of the sleeve stays much