Cyanine vs Pthalocyanine
which is better, or have a longer life.
I have 2 NAN-YA disc that is burned a few months ago now totally unreadable
with Samsung CD-ROM. SC152L
Luckily my ARTEC CDRW still can read it and i quickly backup all my data to Ritek and
prodisc(black) CDRs.
Is pthalocyanine disc reliable?

or cyanine is better?
or it depends on manufactures

Ppl seems to use Taiyo's disc only?
but is ritek and prodisc reliable?
but they are short, not long.......
do u have any pthalo. dye disc die on u?

Yes, many Pthalo CDRs died on me as well as other people (Mitsui). Gold CDs seems to last longer, but they die too, though none of mine have died already.

Tayo Yuden may manufacture very rubust CDR. But not having found some dead ones doesn't prove they don't exist.

The thread for dead CDRs : http://forums.afterdawn.com/thread_view.cfm/3247

And don't forget to check the CDR media section of our FAQ

But most website said that phthalo can stand up to 100 years!

......read the FAQ

Ritek is quite ok

I've also learned that sunlight will make a CDR die even faster

if i leave me disc under sunlight for a few hours (maybe 20?),
then, i'll check again wether the disc is damaged or not
...is this an appropriate way to test the longevity of CDRs?

If the disc can really stand the sunlight for 20 hours without producing any yellow sectors, then can i conclude that Ritek is a good disc manufacturer?

thanks

I have a bunch of old Mitsui discs, about 4 years old, which are now totally unreadable, despite the CDs themselves appearing to be in perfect condition (no visible scratches or marks). I've had better luck with prodisc.

I prefer Azo by Mitsubishi Chemical Media (sold by Verbatim overseas Japan)
Because they are cheaper than Taiyo Yuden and Mitsui in a nearby shop.

At the shop there were:
Mitsubishi: 1980yen/50discs Spindle Tub
Taiyo Yuden: 3280yen/50discs Spindle Tub
Mitsui: no Spindle Tubs

I don't like hearing people have had Mitsui's "die". All of my audio CDR's are either Mitsui (Mainly Gold Ultra II, a few Gold Ultra and a few Golden Dye) or Taiyo Yuden TDK's. I thought Mitsui were up there with TY.

Edit: Just remembered that the only CDR I've had die that wasn't caused by bad treatment was a Mitsui burned in a Yamaha. I notice in the "dead CDR thread" one person mentions Mitsui's burned with a Yamaha that are dead and Mitsui's burned with a Teac that are fine so hopefully I don't have anything to worry about with Mitsui's burned in my Teac or Lite-On.

I've got plenty of other discs that were burned in the Yahama that have had every bad treatment possible. Heat, sunlight, UV light, water, scratches, alcohol based permanent markers, etc, and they read at full speed read with cd-speed. Haven't ever scanned them for C1/C2 with my Lite-On.

It makes me wonder what some people are doing to their discs for them to become unreadable but I suppose it'll happen to me one day.

-dave

I've tested, i leave one of my RiTEK disc under direct sunlight
no jewel casing nothing, just direct sunlight
for 2 hours
I think i would continue to expose it to more long hours of sunlight tomorrow

I think my samsung cdrom drive must be crazy coz the yellow boxes turn out
to be less than before the disc was expose under direct sunlight.

When the disc is runned under ARTECs CDRW, the percentage of
yellow box is actually 0% and it can still be read at 40x
and higher


No data loss!

NOW Can i conclude that Ritek CDRs are good?

or should i test it this way
pour some oil and wash it with detergen
then, try reading it again

How about just waiting a few years. Exposure to direct sunlight for a short time is very different than exposure to room light for a period of years (despite that it may seem similar -- the time factor aspect can only be simulated, never proven).

An example of this -- health differences if you run a marathon (then sit around constantly) vs. getting moderate exercise over a period of several years.

It is in the specs of CD-R's that they can take a couple of hours of direct light (of specified intensity).
I remember (having read a test) that the most important factor in CD-R life is storage temperature. Any temp above 25 C seemed to shorten the lifespan considerably.

(Sorry, can't realy prove it)
--
Ge Someone

Very interesting, could you try to find back this article ? I hope it was not from me

My CDs usually stands 30°C for two monthes in summer. Same CDRs stand a bit less in my father's house and they lasted a bit longer.

50 % of mine were dead while none of his were. Several monthes later (now) 100 % of mine are dead and 50 % of his ones are dead.

At first sight there is no visible alteration, but scanning an old and a recent one reveals the yellow coloration :



Complete analysis of these CDRs here : http://www.hydrogenaudio.org/forums/index....t=0&#entry87185

Dgover2, the Teac/Yamaha Mitsuis were mine. The Teac ones are dead too, now, they just lasted a bit longer. At the present time, only my gold CDRs survived.

The fact that the metallic layer seems to be the cause of early death invalids accelerated aging tests like sun exposure and maybe also UV/heat/moisture exposure that lead to 100 years life expectancy. These tests, especially sun exposure, rather attacks the photosensitive layer than the metallic one.
Someone in a thread mentioned that silver (CDRs are made of silver or gold, unlike pressed CDRs that are made of aluminium) turns yellow when it is exposed to sulphur. Maybe the SO2 in my town is responsible for my dead CDRs.

Here's the SO2 in the air near my flat for march 2003. Quite average.



EDIT : compared to june's data, these one are rather high. In June the SO2 oscillated between 0 and 10 µg/m3 with some peaks at 20 µg/m3

Given that the average urban SO2 concentration in the US (2000) was 15.4 ug/m3, it appears as if just about everyone will have similar problems if they are indeed a result of SO2 emissions.

Many of my Mitsuis which died had not been touched at all over the course of 3-4 years. A couple of them were CDs that I burned, put in cases, totally forgot about (sitting in a drawer somewhere) and then found again, only to discover they were unreadable despite no visual damage.

However, they were all burned with a Yamaha CD burner, which is what I have used since I started burning CDs, so it's interesting that you mention about the problems with Mitsui/Yamaha, although I can't see how one burner would burn a CD any different than another.

Also: All the Mitsuis which I've had die on me were silvers. I haven't really tried the gold mitsuis.

I never had any Mitsui Gold.