--- So, dye-based inks make for the best color compared with pigment-based ink, but,
they're not as resistible to light and open air, which cause photos to fade. Takizawa: Yes, well done (laughs).--- But ChromaLife100 colors keep for 100 years in an album, right? How did you beef
them up? Weight-lifting? Endurance training? Or maybe bunching particles together to make bigger, more resilient
particles? Takizawa: That's not really on the cards (laughs). You see, it's the small particle size that gives
dye-based colors their translucence and vibrancy, so you have to use a different approach to boost their color
retention.--- And what might that be? Takizawa: Things get a little specialized here. The molecules of dyes consists of substances with
a molecular weight of about 600-1,000. --- Let's see, those molecules are collections of atoms of elements such as oxygen,
hydrogen, nitrogen, sulfur and so on, right? Are you by any chance saying that you know the exact structure
of those molecules? Takizawa: Well, no, not all, but I have a pretty good idea of the basic components.
--- Wow, that's amazing. Takizawa: Even under normal conditions, weak points in the structure begin to degrade through exposure
to light and gases in the air. For example, one common group of dyes called, azo dyes, contain molecular components
known as azo groups that feature two linked nitrogen atoms, and those bonds tend to split apart. So what we
do is protect that N=N bond.--- How exactly do you do that? Takizawa: Well, for example, you can do it three-dimensionally, by hiding the fragile component
deep within the structure, or you can surround the dye molecule with another molecule linked to the azo group,
and protect it that way.
--- In other words, you give the dye molecules a protective coating? Takizawa: That's right. Another protection method is to introduce "decoys", molecules
that have no relation to color producing components, but protect them by serving as alternative targets to
be sacrificed to ozone and other gases .--- Decoys, eh? Takizawa: Yes. In other words, we add vulnerable components to locations that are at a distance
from the vital color producing components, or we modify the structure of non-essential parts to make them vulnerable
to attack, thus drawing ozone, NOx and so on away from the pieces that are most crucial to color.--- So it's a little like using bait, right? You surround the king with a bunch of
knight who absorb all the attack, leaving the king unharmed, eh? But wait a minute, can the color still express
itself with such protection added? Takizawa: There'd be little point in the whole exercise if it didn't, so we just make the ink in
such a way that the color is expressed willy-nilly.--- That's pretty amazing! |
