Coincidentally as pharmacist was doing his testing on lightfast inks, I was also on a similar mission to offer superior inks more closely matching Epson Claria. I had dropped hints of what was forthcoming in past threads.
In discussion with an ink chemist and a very good one at that, this is what I learned.
First overall aspect that needs to be understood is this.
As a rule, dyes that have good UV fade resistance have inversely bad ozone fade resistance. If you don’t use paper with a coating that swells around the ink droplet to protect it from air, dyes that might be very lightfast will fade very quickly due to ozone.
So in general very lightfast inks do not perform well in ozone resistance. Why this upside down relationship, you ask?
Here's the reason why.
Color is due to conjugated double bonds in a dye molecule. When the bonds are broken, color is reduced.
Dyes that are good for UV light fastness generally have a metal atom like copper complexed into the dye molecule. When a photon ( UV) breaks a bond ( the bond is made by shared electrons between two carbon atoms), the metal atom limits the damage because metal atoms are electron rich and donate electrons to the bond.
Ozone breaks a bond due to oxidation. The electrons in the metal atom in a lightfast dye actually help promote the oxidation and destruction of the double bond, in layman’s terms.
Apparently Epson's competitor had once forgotten this relationship. Unfortunately Pharmacists test did not include or exclude the ozone content or determined how much was present.
With that in mind, I ended up getting something that is promised to be balanced in most aspects.
It is said, there's no free lunch. Maybe it is true that you can't get something for nothing.
Don't ask me to explain further because I won't be able to very well, I am not an ink chemist by trade. These will be soon available after profiles are developed...just waiting to be scanned and put through the computer......not that profiles are really necessary for most with this inkset. Really.
In discussion with an ink chemist and a very good one at that, this is what I learned.
First overall aspect that needs to be understood is this.
As a rule, dyes that have good UV fade resistance have inversely bad ozone fade resistance. If you don’t use paper with a coating that swells around the ink droplet to protect it from air, dyes that might be very lightfast will fade very quickly due to ozone.
So in general very lightfast inks do not perform well in ozone resistance. Why this upside down relationship, you ask?
Here's the reason why.
Color is due to conjugated double bonds in a dye molecule. When the bonds are broken, color is reduced.
Dyes that are good for UV light fastness generally have a metal atom like copper complexed into the dye molecule. When a photon ( UV) breaks a bond ( the bond is made by shared electrons between two carbon atoms), the metal atom limits the damage because metal atoms are electron rich and donate electrons to the bond.
Ozone breaks a bond due to oxidation. The electrons in the metal atom in a lightfast dye actually help promote the oxidation and destruction of the double bond, in layman’s terms.
Apparently Epson's competitor had once forgotten this relationship. Unfortunately Pharmacists test did not include or exclude the ozone content or determined how much was present.
With that in mind, I ended up getting something that is promised to be balanced in most aspects.
It is said, there's no free lunch. Maybe it is true that you can't get something for nothing.
Don't ask me to explain further because I won't be able to very well, I am not an ink chemist by trade. These will be soon available after profiles are developed...just waiting to be scanned and put through the computer......not that profiles are really necessary for most with this inkset. Really.