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The universal recycling symbol (U+2672 ♲ universal recycling symbol or U+267B ♻ black universal recycling symbol in Unicode) is an internationally recognized symbol used to designate recyclable materials. It is composed of three mutually chasing arrows that form a Möbius strip (an unending single-sided looped surface).
In 1969 and early 1970, worldwide attention to environmental issues culminated in the first Earth Day. In response, then Chicago-based Container Corporation of America, a large producer of recycled paperboard which is now part of Smurfit-Stone Container, sponsored a contest for art and design students at high schools and colleges across the country to raise awareness of environmental issues. It was won by Gary Anderson, a 23-year-old college student at the University of Southern California, whose entry was the image now known as the universal recycling symbol.
The recycling symbol is in the public domain, and is not a trademark. The Container Corporation of America originally applied for a trademark on the design, but the application was challenged, and the corporation decided to abandon the claim. As such, any one may use or modify the recycling symbol, royalty free.
Though use of the symbol is regulated by law in some countries, countless variants of it exist worldwide. Anderson's original proposal had the arrows form a triangle standing on its tip — upside down compared with the versions most commonly seen today — but the CCA, in adopting Anderson's design, rotated it 60° to stand on its base instead.
Both Anderson's proposal and CCA's designs form a Möbius strip with one half-twist by having two of the arrows fold over each other, and one fold under, thereby canceling out one of the other folds. However, most variants of the symbol used today have all the arrows folding over themselves, producing a Möbius strip with three half-twists. Existing single half-twist variants of the logo do not generally agree on which of the arrows is the one to fold underneath. The logo is usually displayed with the arrows circulating clockwise, but the underlying Möbius strip exists in two topologically distinct mirror-image forms of opposite handedness.
The American Paper Institute originally promoted four different variants of the recycling symbol for different purposes. The plain Möbius loop, either white with an outline or solid black, was to be used to indicate that a product was recyclable. The other two variants had the Möbius loop inside a circle — either white on black or black on white — and were meant for products made of recycled materials, with the white-on-black version to be used for 100% recycled fiber, and the black-on-white version for products containing both recycled and unrecycled fiber. For example, a paper envelope might have both the first and last of these four symbols, to indicate that it was recyclable, and made from both recycled and unrecycled fibers.
In addition to the resin identification codes 1-7 in the triangular recycling symbol, Unicode lists the following recycling symbols:
- U+2672 ♲ universal recycling symbol
- U+267A ♺ recycling symbol for generic materials
- U+267B ♻ black universal recycling symbol
- U+267C ♼ recycled paper symbol (indicates product contains recycled paper)
- U+267D ♽ partially-recycled paper symbol (indicates product contains partially recycled paper)
- U+267E ♾ permanent paper sign (e.g. for acid-free paper)
An ISO/IEC working group has researched and documented some of the variations of the recycling logo currently[when?] in use, and has made recommendations for adding some more of them to the Unicode standard.
Resin identification code 
In 1988, the American Society of the Plastics Industry (SPI) developed the resin identification code which is used to indicate the predominant plastic material used in the manufacture of the product or packaging. Their purpose is to assist recyclers with sorting the collected materials, but they do not necessarily mean that the product/packaging can be recycled either through domestic curbside collection or industrial collections. The SPI symbols are loosely based on the Möbius loop symbol, but feature simpler bent (rather than folded over) arrows that can be embossed on plastic surfaces without loss of detail. The arrows are formed into a flat, two-dimensional triangle rather than the pseudo three-dimensional triangle used in the original recycling logo.
The different resin identification codes can be represented by Unicode icons ♳ (U+2673), ♴ (U+2674), ♵ (U+2675), ♶ (U+2676), ♷ (U+2677), ♸ (U+2678), ♹ (U+2679), and ♺ (U+267A).
Other variants 
♾, an infinity sign (∞) inside a circle represents the permanent paper symbol, used in packaging and publishing to signify the use of durable acid-free paper. In some ways, this logo expresses the opposite intention from the recycle logo, in that the acid-free paper is intended to last indefinitely, rather than being recycled. Nevertheless, acid-free paper does not usually contain toxic materials (although certain inks do), so it is easily recycled or composted.
A satirical version of the classic recycling logo also exists, in which the three arrows are twisted from a circular pattern to pointing radially outward, thus symbolizing wasteful one-time usage rather than environmentally friendly recycling. This message is reinforced by the circular inscription, "THIS PROJECT WAS ENVIRONMENTALLY UNFRIENDLY", surrounding the modified logo. The satirical logo appears in the 1998 catalog of an installation art work in Bayonne, New Jersey, in which the artist Steven Pippin modified a row of glass-doored washing machines in a laundromat to operate as giant cameras. The cameras were used to take sequential photographs in the manner of pioneering stop motion photographer Eadweard Muybridge. The front-loading washing machines were then used to develop and process the 24 inch (61 cm) diameter circular film negatives. For technical reasons, the processing of the film was very inefficient in its use of photographic chemicals, perhaps prompting the use of the ironic logo. It is not known whether this particular variant of the recycling logo was used prior to or subsequently to its appearance in the art catalog.
- Jones, Penny; Jerry Powell (May 1999). "Gary Anderson has been found!". Resource Recycling: North America's Recycling and Composting Journal: pg.1–2. Retrieved 2011-05-26.
- "Rules Governing Use of Recycling Logo". Recycling Expert [website]. recyclingexpert.co.uk. Retrieved 2011-05-16.
- Everson, Michael (co-editor); Asmus Freytag (co-editor). "Background information on Recycling Symbols". ISO/IEC JTC1/SC2/WG2 N2342. ISO/IEC. Retrieved 2011-05-26.
- Pippin, Steven John; San Francisco Museum of Modern Art (1998). Laundromat locomotion : Mr. Pippin : [on the occasion of the Exhibition Laundromat Locomotion] (SoftcoverISBN 90-5705-094-3.). [Amsterdam ; Dresden]: Verlag der Kunst.
See also 
- Green Dot symbol
- List of international common standards
- Recycling codes
- Japanese recycling symbols
- Resin identification code – SPI resin identification coding system (NA Society of the Plastics Industry) for classifying different recyclable plastics.
- Jones, Penny; Powell, Jerry. "Gary Anderson has been found!". Resource Recycling: North America's Recycling and Composting Journal, May 1999. 
- Everson, Michael; Freytag, Asmus (2001-04-02). "Background information on Recycling Symbols" (PDF), ISO/IEC Working Group Document N2342
- 44 Recycle Logos and Symbols
Media related to Recycling symbols (3 arrows - folded) at Wikimedia Commons