{{Infobox media
| name = Flexplay
| logo = 
| image = 
| caption =
| type = optical disc
| encoding = 
| capacity = 4.7 GB (single layer), 8.5 GB (dual layer)
| read = 
| write = 
| standard = 
| owner = 
| use = Rental Videos
| extended from = 
| extended to = 
}}

'''Flexplay''' is a trademark for a DVD-compatible optical video disk format with a time-limited (usually 48-hour) playback time. They are often described as "self-destructing" although the disc merely turns black and does not physically disintegrate. The same technology was used by Disney's Buena Vista releasing company under the name '''ez-D'''. The Flexplay concept was invented by two professors, Yannis Bakos and Erik Brynjolfsson, who founded Flexplay Technologies in 1999. The technology was developed by Flexplay Technologies and General Electric.

The intended market for the EZ-D discs was short-term hire and promotional deals. Since the disc was capable of being used in any standard DVD player, the manufacturers hoped it would succeed where other time-limited DVD technologies, such as DIVX, failed. Test marketing began on August 2003 and was canceled early when consumers rejected the concept (partly due to environmental issues).

'''SpectraDisc''' was another such technology, and in January 13, 2003 Flexplay Technologies acquired all of the SpectraDisc Corporation assets. [http://www.flexplay.com/News_press_spectradisk.htm] SpectraDisc DVDs worked same way as Flexplays, only not starting as red and turning blue instead of black. The addition of the red layer to Flexplay discs may be in order to protect the expired discs from being read in next-generation players using blue lasers, for which the oxidized blue-color layer is essentially transparent.

==Specifications==
Flexplay discs do not bear the DVD logo. When asked whether Flexplay discs do or do not comply with DVD forum standards, a company spokesperson replied that "Flexplay DVDs are produced to be readable in DVD players adhering to DVD Forum specifications."

A Flexplay disc is shipped in a vacuum-sealed package. There is a clear dye inside the disc, contained within the bonding resin of the disc, which reacts with oxygen. When the seal is broken on the vacuum-packed disc, the layer changes from clear to black in about 48 hours, rendering the disc unplayable. If unopened, the shelf life of the sealed package is said to be "about a year." The DVD plastic also has a red dye in it, which prevents penetration of the disc by blue lasers, which would go straight through the oxygen-reactive dye.

The Flexplay discs are dual-layer DVD-9 discs. The change against standard DVDs is the composition of the resin adhesive holding the inner and outer layer together, which is sensitive to oxygen and darkens within a pre-set time, usually 48 hours, when exposed to air. The replacement of the adhesive results in only minimal altering to the DVD manufacturing process. The time of the darkening can be influenced by varying the exact composition of the resin. For the DVD-5 discs, where there is no layer of bonding resin in the optical path, surface coating can be used.

According to the vendor, "Flexplay discs are fully recyclable and conform to all applicable EPA environmental standards." Some environmental groups have endorsed the product due to Flexplay's recycling plans and partnership with environmental industry leaders such as GreenDisk, leading to the creation of the first DVD recycling operation. Others such as the Grass Roots Recycling Network nevertheless have objected to the creation of a short-lived "disposable" version of a traditionally durable product.

==Chemistry==
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The reactive layer comprises a polymer resin that acts as a carrier for a suitable leuco dye, which, upon contact with atmospheric oxygen, oxidizes to form an opaque or semi-opaque material.  

Some of the dyes used are reduction using a suitable reducing agent. The method commercially used by Flexplay and SpectraDisc employs methylene blue reduced by sodium dithionite.

In order to prevent the oxidation being triggered during manufacture of the discs, and in order to avoid the need for operating in inert atmosphere, the leuco dyes are further chemically modified to their blocked forms. Such blocked leuco dyes are the leuco dye precursors that form the leuco dye by a slow, controlled chemical reaction. Leucomethylene blue can be reacted with water, the blocked leuco dye compound undergoes hydrolysis, releasing the unblocked leuco dye. This reaction is slow (several days to a week), and the hydrolytic compound is supplied either as atmospheric moisture, or in the formulation of the resin.

The rate of the deblocked leuco dye oxidation is dependent on the pH of the resin polymer matrix. By adding basic compounds (e.g. 1,4-diazabicyclo[2.2.2] octane (DABCO), or other amines), the pH is increased, and the reaction rate increases correspondingly. Correspondingly, by adding strong protic acids (e.g. camphorsulfonic acid), the reaction rate can be decreased and the lifetime of the disc prolonged.

The residual oxygen can be removed from the substrates used for disc manufacture by storing them under vacuum or oxygen free atmosphere (e.g. pure nitrogen) for a period of time (hours to days). Alternatively, an oxygen scavenger (e.g. iron(II) salts, tin(II) salts, or organometallic compounds) can be added to the polymer formulation, reacting with the oxygen present in the polymer matrix in shorter timeframe than the hydrolysis of the blocked leuco dye takes.

The reaction timing can be further controlled by addition of other substances. As the diffusion rate of oxygen through the polymer layer is more or less constant, a supply of suitable antioxidants (eg. organometallic compounds) which react with the oxygen preferentially to the leuco dye leads to gradual depletion of the antioxidant compound. Only after the antioxidant is consumed, the leuco dye starts being oxidized, achieving the period of delay of the reaction onset, followed by a rapid reflectivity degradation. Stannous ethylhexanoate can be used here as the antioxidant organometallic. Various resin-soluble tin(II) and iron(II) compounds can be used, e.g. chelates and fatty acid salts. Other usable compounds are e.g. hydroquinones, alkylhydroxylamines, dithionates, reducing saccharides (e.g. glucose), alpha-hydroxyketones (acetol), substituted boron hydrides and silicon hydrides. 

'''48DVD'''（よんぱちでぃーぶいでぃー）はレンタルDVDを代替するすべく低価格で提供され、発売前は大きな話題となったが、登場した当初よりレンタルDVDが普及する中での48DVDの意義を疑問視する声が多く、販売用は3タイトルが登場しただけで、2006年には販売終了になった。

ディスクに特殊な塗料が塗られていて（表面が赤い）、真空パックされた状態で販売される。開封と同時に塗料が酸化していき、徐々にディスクの塗料が赤から黒に変化し、最終的にドライブのレーザーを通さなくなり、そのディスクは視聴できなくなる。
過酷な環境で視聴されることを想定してマージンをとってあるため、実際には48時間以上経過しても視聴できる場合が多いが、ディスク品質が悪化していくのは確実である。また、開封しなくても塗料の酸化が完全に止まっているわけではないため、開封前の保存可能期間は約1年とされている。また、開封後すぐにパソコンなどで複製してしまえば、その後も保存することが可能である問題点もあった。

「廃棄物の増加につながる」として米国では環境保護団体から抗議を受けた（これについては英語版参照）。