Digital BW, The Print

Jeff,

>Does anyone out there know what the story behind the Wilhelm Imaging
>Research, Inc.  web site ?

>... So many paper and ink
>manufactures refer to his testing and results. ...

Pardon my cynicism, but you may have answered the question.

I suspect it is really hard to keep the big-money clients happy while still
doing good science.

Once one tries to deal with all the potential oxidizers in the air and other
variables the problems may become almost insurmountable.

A "display life" representation has always seemed a bit shaky to me.  "200
years of display life (in a vacuum by candle light...)" probably doesn't
make the best ad copy.

(I think I am now noticing dark-storage warming and fading of my test
strips -- which are not kept in a vacuum.)


Paul
http://www.PaulRoark.com

>>(I think I am now noticing dark-storage warming and fading of my test
strips -- which are not kept in a vacuum.)<<

With any particular paper ink combos or all of them?

Thanks,
Doug

Doug,

I have not done a survey of old test strips, but the ones that caught my
attention were some old Piezo on EAM test strips that I wanted to compare
current results to.  I suspect that it affects all of them.  If the process
is oxidation, then even dark stored prints would be expected to "age," even
if at a rate that is much slower than one exposed to light.

Paul


>>(I think I am now noticing dark-storage warming and fading of my test
strips -- which are not kept in a vacuum.)<<

>With any particular paper ink combos or all of them?

Paul Roark wrote:

>   If the process
> is oxidation, then even dark stored prints would be expected to "age," 
> even
> if at a rate that is much slower than one exposed to light.
>
> <http://docs.yahoo.com/info/terms/> 

The process GENERALLY (in acid-free papers) is the result of either 
light or gaseous interactions.

Light induced fading can be tested for by placing the print in a vacuum 
and exposing it to light..

Gaseous interactions are generally  either oxidation or the results of 
free-radicals (chlorine, ozone, etc.)..

That's why the "display behind glass" figures are so pointless to me 
except as a baseline for generalized comparisons (like EPA gas mileage 
figures).  The amount of gaseous interaction "behind glass" is so 
reduced from what the average print sees in lits lifetime that it bears 
little relationship to reality...

The sad fact?  Most of these gaseous interaction problems have been long 
known in the dyestuff industry.  As an example, the cyan dye 
disappearance that lays at the heart of the problem with 1270/1280 OEM 
inks has been know as "Gulf Coast Fading" and recognized in the US 
chemical indsutry since 1955..  

The OEM manufacturers tend to develop inks incrementally, changing 
colors bit by bit in each inkset to increase longevity.. The problem 
with the 1270/1280 cyan dye was it had been changed from the previous 6 
color inksets to increase lightfastness.. BUT, EPSON never tested for 
gaseous interactions in general environmental conditions.. They ASSUMED 
that their changes left that part of the inks characteristics 
unchanged... DUMB move!  But, they "needed to get the product out the 
door in conjunction with their standard release cycle."  

AND, as we all know, the real dyes/pigments are not OEM developments... 
they are developed by the Chemical Companies and simply incorporated 
into carriers for the particular printers.  That's part of why I prefer 
dealing with ink/chemical companies for my inks.

[Keith]
 
 




[Non-text portions of this message have been removed]

Wednesday, May 22, 2002, 12:56:29 PM, Editor P.O.V. Image Service wrote:

EPOVIS> Paul Roark wrote:

>>\ufffd\ufffd If the process
>> is oxidation, then even dark stored prints would be expected to "age," 
>> even
>> if at a rate that is much slower than one exposed to light.
>>
>> <http://docs.yahoo.com/info/terms/> 

EPOVIS> The process GENERALLY (in acid-free papers) is the result of either 
EPOVIS> light or gaseous interactions.

EPOVIS> Light induced fading can be tested for by placing the print in a vacuum 
EPOVIS> and exposing it to light..

EPOVIS> Gaseous interactions are generally\ufffd either oxidation or the results of 
EPOVIS> free-radicals (chlorine, ozone, etc.)..

EPOVIS> That's why the "display behind glass" figures are so pointless to me 
EPOVIS> except as a baseline for generalized comparisons (like EPA gas mileage 
EPOVIS> figures).\ufffd The amount of gaseous interaction "behind glass" is so 
EPOVIS> reduced from what the average print sees in lits lifetime that it bears 
EPOVIS> little relationship to reality...

EPOVIS> The sad fact?\ufffd Most of these gaseous interaction problems have been long 
EPOVIS> known in the dyestuff industry.\ufffd As an example, the cyan dye 
EPOVIS> disappearance that lays at the heart of the problem with 1270/1280 OEM 
EPOVIS> inks has been know as "Gulf Coast Fading" and recognized in the US 
EPOVIS> chemical indsutry since 1955..\ufffd 

EPOVIS> The OEM manufacturers tend to develop inks incrementally, changing 
EPOVIS> colors bit by bit in each inkset to increase longevity.. The problem 
EPOVIS> with the 1270/1280 cyan dye was it had been changed from the previous 6 
EPOVIS> color inksets to increase lightfastness.. BUT, EPSON never tested for 
EPOVIS> gaseous interactions in general environmental conditions.. They ASSUMED 
EPOVIS> that their changes left that part of the inks characteristics 
EPOVIS> unchanged... DUMB move!\ufffd But, they "needed to get the product out the 
EPOVIS> door in conjunction with their standard release cycle."\ufffd 

EPOVIS> AND, as we all know, the real dyes/pigments are not OEM developments... 
EPOVIS> they are developed by the Chemical Companies and simply incorporated 
EPOVIS> into carriers for the particular printers.\ufffd That's part of why I prefer 
EPOVIS> dealing with ink/chemical companies for my inks.

EPOVIS> [Keith]
 
 




EPOVIS> [Non-text portions of this message have been removed]


EPOVIS> Yahoo! Groups SponsorADVERTISEMENT

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Hello,

My 1160 is on the way, as is, a set of FS carts from MIS. Can anyone
give me an approximate idea of how many 13x19 prints one can get on
average from one set of carts?

Thanks.

Best regards,
 Richard  

mailto:richard@...

Jeff,

I am glad someone finally asked the question.
 
I thought that maybe you had to have a secret code to unlock the
information.  Or, the information was only contained in a newsletter,
and that I was the only one who didn't know about it.

Now there is only the message "Our website is temporarily down for
reconstruction and expansion.  We will be up and running again very soon
with image permanence information for many exciting new printers, inks,
and papers!"  That is a change from last week, which promised to be up
by 5/21.

At least as a public web site, Wilhelm Imaging Research "isn't wearing
any clothes."

Bob Rose



Does anyone out there know what the story behind the Wilhelm Imaging
Research, Inc.  web site ?

For the past 1 \ufffd years or more I have periodically  gone to the
site looking for permanence information. So many paper and ink
manufactures refer to his testing and results. For the past 1 \ufffd years
his web site has been continually updated with a promise of a new
report
in a few weeks. When the promise date arrives a new promise date is
posted for another few weeks or months down the road and the cycle
continues.
Now we all have delays but this
seems very odd.

What is this all about ?  Any ideas ? Any inside info?


-Jeff