Digital BW, The Print

John,

>Do you notice any difference in apearance between the print 
>sprayed with Lascaux and Print Guard.

I do see the dmax advantage of Lascaux in side-by-side test strips.  Other
than that they look the same to me.

> I've been using Priemier Art 
>Print Shield and have not been able to detect its presence after 
>spraying. Can you "See" either of the other products, any gloss, Etc.

To me, when I just do 3 light coats, the images look the same as the
unsprayed prints.  The paper white, for example, is unchanged.  On many
matte papers the dmax is also unchanged with light spraying.

>Also, do you know what the Laquer formula is for either the Print 
>Guard or Print Shield.

No, I don't know what they are made of.  The Premier Imaging people call it
a "lacquer" instead of an acrylic, but I often think of the term "lacquer"
as just generic.  Many of the traditional lacquers, such as nitrocellulose
lacquer, yellowed.  Acrylic, on the other hand, has about the best
reputation for not yellowing.  So, when a company tells me the product is a
"lacquer" and not acrylic, this is not really a positive statement.  

On the other hand, the Wilhelm, de facto, stamp of approval for PremierArt
Print Shield does carry some weight with me.  It and Lascaux (B72 formula)
are at the top of my list (PremierArt to reduce bronzing on glossy paper,
and Lascaux for the matte papers).  Grumbacher Tuffilm is just down a notch,
having a nozzle that is not as good, especially for glossy prints; for matte
papers the nozzle is fine. (The Grumbacher fixative is cheap and readily
available, but I have not tested it for dmax decrease on UltraSmooth or
Scrapbook.)  There may be other great clear coats, but if they are unknown
proprietary formulas, they are, I believe, going to need some age testing to
be accepted in the fine art field. 

Paul
www.PaulRoark.com
____________________________



--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul Roark" 
<paul.roark@v...> wrote:
> Steve wrote:
> 
> >I have been using Lyson Print Guard (same product) on my HPR 
prints for
> >framing without glazing.  It looks fine but a measured step wedge 
will show
> >a significant shift in density post spraying, including a large 
drop in
> >dMax.
> 
> 
> I've seen and measured this with UltraSmooth and PremierArt Print 
Shield,
> which, as you note, appears to be the same as Lyson Print Guard 
(though the
> Premier Imaging people deny they are the same).
> 
> Perhaps related to this is the observation by another forum member 
that the
> surface of smooth prints can feel a bit gritty after spraying with
> PremierArt Print Shield, at least when used in hot, dry 
conditions.  After
> looking into it, this person concluded that the solvents in the 
PremierArt
> Print Shield were so quick to dry that the coating was starting to 
solidify
> before hitting the print.  Lascaux Fixativ, however, uses solvents 
that are
> less volatile and, thus, may keep its acrylic in liquid form long 
enough to
> more effectively surround the pigment particles and lock them to the
> surface.
> 
> Today I did a comparison of the two sprays on UltraSmooth.  I 
sprayed two
> test strips of UltraSmooth with 3 coats of the 2 products.  The 
dmax started
> at 1.61.  The test strip sprayed with PremierArt Print Shield had a 
dmax
> drop to 1.52 and 1.51.  The test strip sprayed with Lascaux Fixativ 
had the
> dmax drop to 1.59 and 1.57.
> 
> Perhaps related to this is my finding that PremierArt Print Shield 
is more
> effective at reducing the bronzing on glossy papers than is the 
Lascaux.
> With Lascaux I'll have to find a different procedure than my usual 
3-4
> quick, light sprays.
> 
> It appears to me that the PremierArt Print Shield tends to stay on 
the
> surface of the print more, whereas the Lascaux appears to soak in 
more.  The
> Lascaux solvents are, apparently, less volatile -- they evaporate 
slower.
> In addition to the chemist's conclusions in this regard, I simply 
can smell
> the Lascaux on the print longer.
> 
> I might add that the drop in dmax does not happen with all matte 
papers.
> UltraSmooth is the paper that I like and use frequently that 
definitely does
> have a tendency to have this happen.  From now on, I might be using 
Lascaux
> on it instead of PremierArt Print Shield.  (The Lascaux is also the 
Rohm &
> Haas B72 formula that is most highly thought of by the conservation
> industry.)
> 
> Paul
> www.PaulRoark.com