DVD stands for either Digital Versatile Disc or Digital Video Disc. The "R" in DVD-R stands for "recordable." This means the disc will be used to record one time, and will become a read-only disc that cannot be recorded on again. This differs from the suffix "RW," which means "rewritable," and indicates a disc can be recorded again and again. Since DVD-R discs are only recorded one time, it's often important to choose a top-quality disc. Look for several factors to help ensure top quality.
Standard CDs, DVDs and Blu-rays in the ROM, R, and RW/RE formats employ an aluminum alloyed reflective layer for the data to be read by the drive's laser. Due to the properties of aluminum, it is highly susceptible to corrosion which can therefore shorten the lifespan of the disc. Consequently, 24 carat gold and occasionally pure silver replaces aluminum for some manufacturer discs to combat corrosion.
Aluminum disc layers can start to rust immediately after coming into contact with air. To a lesser extent, silver will oxidize, but at a slower rate-its weakness for tarnishing is its contact with sulfurous materials. Traditionally, a protective lacquer coating is meant to shield aluminum and silver alloyed layers and well as the disc's subsequent layers from environmental factors, but it's not always impenetrable. Corrosion of these discs will still occur even with the use of a hard lacquer.
The use of gold in a disc's reflective layers provides manufacturers with a significant upgrade in the quality and shelf life of CDs, DVDs and Blu-rays. Pure gold does not oxidize in air or water as well as in most other elements it could encounter under normal circumstances. Therefore, gold maintains its luster for reflective purposes over a longer period of time.
For example, one manufacturer tested that gold-based reflective layers can endure a greater dose of prolonged UV, humidity and heat exposure in conjunction with a high grade of Phthalocyanine dye. This manufacturer calculated and claimed the disc's lifespan to be at approximately 300 years, which defeats the average 25-100 year lifespan of aluminum layered discs.
Gold archival discs are available for CD-R, DVD-R and BD-R formats. The quality and durability is reflected in the price of the media. Currently, gold discs are more than quadruple the price of their aluminum layered counterparts. It should be noted however that gold discs are not any stronger than standard manufacturer discs when encountering the impact of physical damage.
Source: cd-info
Instructions
* Check the color as an initial guide. The underside of the disc is coded by color and is sometimes indicated on the box label. Gold discs are often considered to be the best quality, though other colors can be just as good.
* Check the label for the kind of dye used in manufacturing, as this is more important than actual color. The dye used to create the color is indicative of the quality of the disc. The highest quality is a phthalocyanine dye.
* Check the brand. High-quality brand names often use manufacturers who offer the better product. Verbatim and JVC Taiyo Yuden are considered top quality, as of October 2010.
* Check the country where the discs are manufactured. For brand-name suppliers, Taiwan and Japan are considered to manufacture the best quality, with Malaysia and China manufacturing the worst. Generic names that come from Taiwan are too often bulk produced with low quality.
Source : ehow
Gold Archival CD/DVD Media
The use of the precious metal gold is implemented for optical media with the intent of extending longevity, especially for archival purposes. Backup storage is essential for home, commercial and industrial purposes, but the average disc may not provide the reliability and durability of a sustainable shelf life.
Standard CDs, DVDs and Blu-rays in the ROM, R, and RW/RE formats employ an aluminum alloyed reflective layer for the data to be read by the drive's laser. Due to the properties of aluminum, it is highly susceptible to corrosion which can therefore shorten the lifespan of the disc. Consequently, 24 carat gold and occasionally pure silver replaces aluminum for some manufacturer discs to combat corrosion.Aluminum disc layers can start to rust immediately after coming into contact with air. To a lesser extent, silver will oxidize, but at a slower rate-its weakness for tarnishing is its contact with sulfurous materials. Traditionally, a protective lacquer coating is meant to shield aluminum and silver alloyed layers and well as the disc's subsequent layers from environmental factors, but it's not always impenetrable. Corrosion of these discs will still occur even with the use of a hard lacquer.
The use of gold in a disc's reflective layers provides manufacturers with a significant upgrade in the quality and shelf life of CDs, DVDs and Blu-rays. Pure gold does not oxidize in air or water as well as in most other elements it could encounter under normal circumstances. Therefore, gold maintains its luster for reflective purposes over a longer period of time.
For example, one manufacturer tested that gold-based reflective layers can endure a greater dose of prolonged UV, humidity and heat exposure in conjunction with a high grade of Phthalocyanine dye. This manufacturer calculated and claimed the disc's lifespan to be at approximately 300 years, which defeats the average 25-100 year lifespan of aluminum layered discs.Gold archival discs are available for CD-R, DVD-R and BD-R formats. The quality and durability is reflected in the price of the media. Currently, gold discs are more than quadruple the price of their aluminum layered counterparts. It should be noted however that gold discs are not any stronger than standard manufacturer discs when encountering the impact of physical damage.
Source: cd-info
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