Pioneer Blu-Ray Disc Drive

Advantages of optical discs with regard to storage lifetime

As the following comparison chart shows, optical discs are characterized by having a long life compared to other methods of storage.

Source (IDEMA Japan News)
http://www.idema.gr.jp/common/pdf/news/tenbo2022.pdf

Why BD-R offers longer term storage than CD-R or DVD-R

The materials used as recording layer are different.

Although CD-R and DVD-R discs can be manufactured at low cost, they utilize an organic recording material that is susceptible to degradation over time.
Conversely, BD-R discs utilize an inorganic recording material that is not susceptible to degradation.

The protection provided to the recording layer is different.

CD-Rs and DVD-Rs feature a coating of organic recording material on top of a substrate. The recording layer has been known to deteriorate due to factors such as water penetrating from the substrate side.
BD-Rs, however, provide a strong level of protection to the recording layer by covering both the upper and lower surfaces of the recording material with a dielectric.

The protection of the disc surfaces is different.

With BD-R the recording surface and outer edge of the disc is hard-coated.
This coating is resistant to scratching, dust, fingerprints, and smudges.

Differences between standard BD-Rs and DM for Archive-compatible BD-Rs

Unique recording layer suitable for long-term storage

Utilizes a unique Metal Ablative Recording Layer (MABL). Recording marks are formed using the ablation method, which is more stable than existing phase-change materials, and is suitable for long-term storage.
Additionally, ablation-based recording is irreversible, offering a true write-once capability that makes data tampering theoretically impossible.

Rigorous quality control

These discs have passed strict quality control by having each disc pass defect and servo inspections using stricter inspection standards than for normal Blu-ray discs.
Additionally, acceleration tests are performed on all lots using inspection standards based on the results of lifetime estimate testing. Only those discs that pass are shipped, reducing the likelihood of data playback faults.

DM for Archive-compatible BD-Rs, offering lifetime archive

ISO/IEC 18630 recommends storing discs in a case away from direct sunlight, in an environment that is as dust-free as possible.
In addition, it is recommended that long-term storage environments be kept at a temperature of between 10 ℃ to 25 ℃ (50 ℉ to 77 ℉), and a relative humidity of 40% to 60%.
The period for which a recorded disc can be read without error when stored in this kind of environment is estimated through experiment.
The method for testing that estimated lifetime (the period for which recorded data can be read without error) is strictly defined in international standard ISO/IEC 16963.

If the estimated lifetime is confirmed as being more than 100 years using this testing method and good, archival-quality records are achieved, then the Grade 100 standards, for which an estimated lifetime of at least 100 years is required, the determining criteria for ISO/IEC 18630, are satisfied.
The following is a simple explanation of ISO/IEC 16963 testing methods.

ISO/IEC 16963 specifies a testing methodology based on the theoretical assumption that estimated lifetime depends only on temperature and humidity, and that lifetime follows a log-normal distribution.
To determine the estimated lifetime at 25 ℃ (77 ℉)/50% based on this standard, recorded discs are subjected to the following four stress conditions.

Discs are subjected to four stress conditions, accelerating disc degradation to determine the failure time when the likelihood of data reading failures is increased.
From that failure time,
Lifetime (logarithm) = β0 + β1 × absolute temperature reciprocal + β2 × relative humidity
Coefficients β0, β1 ,β2 and standard deviation σ are calculated.
The results of third-party (ADTC) lifetime estimate testing based on the ISO/IEC 16963 international standard showed an estimated lifetime* of 6468 years at 25 C (77 ℉)/50%RH.

ISO/IEC 16963 controlled storage conditions (25 ℃ (77 ℉)/50%) anticipates storage in a constantly air-conditioned room. Accordingly, calculating the estimated lifetime at different temperature and humidity based on the results of the above tests produces a graph as follows.
Even in an office environment (30 ℃ (86 ℉)/80% RH), estimated lifetime is at least 100 years.

The results of third-party (ADTC) lifetime estimate testing based on the ISO/IEC 16963 international standard are here:
https://www.verbatim.jp/download/test_report/report_sl_j.pdf

Recommended storage environment for use in long-term storage

Store in a dedicated case

When storing the disc, place in a dedicated disc case for storage.
Storing in a case protects the recording and label surfaces from scratching and dust.

Storage location/Environment

Store in a location away from direct sunlight in surroundings with as little dust as possible.
When storing in an office, a temperature between 5 C and 30 C and relative humidity of 15% to 80% is suitable.

• Extended exposure to direct sunlight may cause the recording layer to degrade, making normal playback impossible.
• Storing at high temperature may cause the disc to deform, making normal playback impossible.
• Storing at low temperature may cause condensation during playback.