Ad
Ad
Ad
Pages: [1]   Bottom of Page
Print
Author Topic: Hahnemuhle Protective Spray  (Read 2569 times)
Mike Sellers
Sr. Member
****
Offline Offline

Posts: 435


WWW
« on: March 20, 2013, 10:01:00 AM »
ReplyReply

Has anyone tried this? It is odorless so that`s good. I wonder if it would do a good job on canvas? I would be worried about the corners cracking while stretching.
Logged
Ken
Full Member
***
Offline Offline

Posts: 179



WWW
« Reply #1 on: March 20, 2013, 10:34:03 AM »
ReplyReply

I've been using it on paper for about a decade because I don't like glass on my framed pieces. It is not odorless! Maybe the smell is only the isopropanol, but it's definitely there. This is from their tech specs PDF:

"The principal safety and health hazards when using the product are due to inhalation of isopropanol vapours. There is also a risk of ignition with the spray product should it pass through or onto an ignition source. Inhalation may occur while spraying the product or during the drying process. If the product is used with adequate ventilation, risk of excessive inhalation is eliminated."

I have used it on canvas and it was fine... no cracks, but I prefer the look of a relatively heavy lacquer look, so I spray a light coat or two before applying something like ClearShield with a roller. The spray coat helps prevent ink smearing on the first roller pass.
Logged
MHMG
Sr. Member
****
Offline Offline

Posts: 624


« Reply #2 on: March 20, 2013, 11:53:32 AM »
ReplyReply

My guess is that HN Protective Spray is rebadged Premier Print Shield, or that both vendors are sourcing their private labeled product from the same manufacturer. Label is different, but the can's design, nozzle performance, viscosity and solvent formulation appear to be identical. You can use them interchangeably without noticing any differences.  Also, samples having been coated with both products are in test at Aardenburg Imaging and the general light fastness enhancement to the samples is the same. I personally and routinely use either product with excellent success on Hahnemuhle Photo Rag Pearl, my favorite satin/luster "traditional photo" paper. This paper has it's own distinctive "look" not closely copied by other media, holds the wet spray coating very well without sag, and dries down beautifully with very little change in surface appearance other than the elimination of all differential gloss (which is relatively low on this paper to begin with, but I'm fanatical about removing all traces).

The challenge to working with low viscosity sprays like HN Protective Spray and Premier Print Shield is applying enough to make a substantive coating (two coats optimal) yet not applying too heavily that the low viscosity solution puddles or sags before drying.

While it can work for canvas, it won't necessarily alter the canvas surface patina which many artists actually intend to do when varnishing (ie. use a varnish for decorative gloss/color gamut enhancement as well impart protective barrier properties.   It's also undoubtedly a very expensive option compared to the aqueous-based varnishes that most people apply with HVLP spray guns or rollers, so most artist wouldn't use it unless they produce only a few canvas prints each month.  The coating resin is acrylic, but not being an aqueous emulsion like ClearStar ClearShield, BC Timeless, etc, it may be more prone to cracking when the canvas is stretched even though the thickness of the coating will be quite low.

The only actual experience I have with HN Protective Spray/Premier Print Shield on a canvas medium is with the Kernewek Fabric "St Ives" (see: http://www.aardenburg-imaging.com/news.67.html ). This is a unique "infused" inkjet medium that retains the weave of the fabric exceptionally well because the inkjet receptor layer is infused into the fabric rather than production top coated like most canvas/inkjet media. The conventional overcoats tend to fill in the weave pattern on the canvas.  Spraying with HN Protective Spray alters the delicate structure of the St Ives fabric very little, and it looks essentially as if no coating was ever applied yet provides some barrier protection.  One artist colleague I print for on the St Ive's fabric will sometimes desire a thicker decorative coating on the Kernewek fabric.  He applies the HN spray as an undercoat on the Kernewek Fabric, then rolls on a top coat of aqueous-based varnish (I seem to recall him saying ClearStar) with very good results. The reason he does this is because testing at AaI&A has shown some chemical compatibility problems with the aqueous chemistry needed to emulsify the resin in the acrylic varnishes and the aqueous pigment based inks (i.e., light fade resistance is impaired rather than enhanced). The HN spray is thus acting as an intermediate barrier coat between the encapsulated ink particles and the aqueous acrylic emulsion chemistry.


cheers,
Mark
http://www.aardenburg-imaging.com
« Last Edit: March 20, 2013, 12:22:58 PM by MHMG » Logged
Mike Sellers
Sr. Member
****
Offline Offline

Posts: 435


WWW
« Reply #3 on: March 20, 2013, 11:56:09 AM »
ReplyReply

Ok thanks.
Is there a difference between a lacquer based spray and a solvent based spray?
Logged
MHMG
Sr. Member
****
Offline Offline

Posts: 624


« Reply #4 on: March 20, 2013, 01:00:03 PM »
ReplyReply

Ok thanks.
Is there a difference between a lacquer based spray and a solvent based spray?

Is there a difference between a lacquer based spray and a solvent based spray?
[/quote]

This question is a little bit out of my realm of expertise, but traditionally lacquers and varnishes have resins suspended in a solvent other than water (water is a solvent, too), typically aromatic hydrocarbons.  The value of acrylic resin emulsions which are water based, is that they tend to be less toxic and easier to clean the tools after application. Beyond that, most folks use lacquer and varnish rather interchangeably, but there are other technical distinctions for those that want to be sticklers for accuracy. For example, a traditional varnish is made up of a resin that is kept in suspension by the addition of thinners and also contains drying oils that will help dry down properties, whereas a lacquer is made up of resin/solvent mixtures that also have dissolved nitrocellulose in them. The film forming properties of acrylic emulsions tend to be poorer at creating coatings with the highest gas and vapor barrier properties compared to resins, even the same acrylic resin, when suspended directly in a solvent rather than emulsified.  I'm sure others on this forum can add further nuances that account for various technical distinctions between acrylic emulsions, resin varnishes, and lacquers. Or google the topic. You will find out more that you ever wanted to know Cheesy

best,
Mark
« Last Edit: March 20, 2013, 01:09:53 PM by MHMG » Logged
Mike Sellers
Sr. Member
****
Offline Offline

Posts: 435


WWW
« Reply #5 on: March 21, 2013, 09:05:07 AM »
ReplyReply

Amazing amount of info on this website! Thanks
Logged
stevenarnott
Newbie
*
Offline Offline

Posts: 15


« Reply #6 on: December 12, 2013, 04:50:54 PM »
ReplyReply

Came upon this topic while searching for something else, but thought I would mention, for the benefit of anyone thinking of trying Hahnemuhle Protective Spray...

It's true that it is generally odorless on the print after it's dried, but it is certainly not odorless when you are applying it! This stuff is pretty nasty, actually. You don't want to breathe this at all, and the smell is strong; it quickly spreads throughout the house, and it's not pleasant.

It works very well, though, so I'm still using it. If it were warmer outside, I would restrict its usage to the outdoors. Since it's cold out, I spray prints just before I'll be leaving the house for a few hours.

Just a heads-up, since the word "odorless" implies something that is not true of this product.
Logged
Dan Berg
Sr. Member
****
Offline Offline

Posts: 1535



WWW
« Reply #7 on: December 12, 2013, 07:19:11 PM »
ReplyReply

Ok thanks.
Is there a difference between a lacquer based spray and a solvent based spray?

You have heard the term solvent based and water based. Lacquer is a solvent based finish.
In laymans terms the lacquer is the solids and what sticks and the solvent gives it the viscosity and what makes it sprayable.
Deft is well known solvent based lacquer in a can. Used for all types of projects
These lacquers are pretty much all a 10/90 blend. Very close to what you have with the Hahnemuhle.
10% solids and 90 % solvent. The solids are what sticks to your project and the solvents evaporate.
The solvents give it the viscosity to spray and have most of the nasty smell and chemicals.
That's why the smell goes away ,after it has flashed off and evaporated you are left with only the dried solid lacquer,thus no more smell.
I deal mostly with catalized finishes in my cabinetry business because of the much higher concentration of solids.
Catalized lacquers have about 37% solids and catalized varnishes about 48% solids. The higher the solids the thicker the build. 2 coats of catalized varnish (conversion varnish)would take 10 coats of deft to equal the same build.
Problem is it is still not the same as the cat finishes are a two part finish almost like an epoxy,really tough stuff.
Biggest issue is they are all full of nasty,nasty stuff.
Toluene,zylene,butyl acetate and formaldehyde just to name a few.

« Last Edit: December 13, 2013, 05:07:11 AM by Dan Berg » Logged

Ken
Full Member
***
Offline Offline

Posts: 179



WWW
« Reply #8 on: December 13, 2013, 01:02:33 PM »
ReplyReply

I have been using this for years on paper and canvas. Great stuff, but at about $16 a can, quite expensive when applying five coats, as I do... and not "odorless" until the propellant has dried. I think it is important to vent this and any other spray because it's not just the propellant that's floating around. Undoubtedly, the lacquer, paint, glue or whatever else you're spraying will settle on all surfaces where you can smell the propellant... including your lungs if you don't wear a mask.
Logged
Bullfrog
Full Member
***
Offline Offline

Posts: 175


« Reply #9 on: December 14, 2013, 05:31:16 AM »
ReplyReply

Has anyone tried this? It is odorless so that`s good. I wonder if it would do a good job on canvas? I would be worried about the corners cracking while stretching.

I use Hahnemuhle spray on paper prints (watercolour and fine art paper) with no complaint.NO.   I would not use it on canvas.

If you are using anything in a can - it has propellants added which are poisonous if inhaled in large quantities and if I was spraying every day, I would strongly urge you to get the proper mask.  ( a regular painter's mask may not be sufficient). 

Solvent based varnishes use mineral spirits or turpentine instead of water to bind the polymers or resins used in the formulation. 

Lacquer is actually derived from an insect or a tree - I am not personally aware of a commercially sold lacquer for application on canvas but won't say it cannot be done.  The issue with giclee printing is the ink may not tolerate it - and only through experimentation does one find out.
« Last Edit: December 14, 2013, 05:46:10 AM by Bullfrog » Logged
Bullfrog
Full Member
***
Offline Offline

Posts: 175


« Reply #10 on: December 14, 2013, 10:14:21 AM »
ReplyReply

Is there a difference between a lacquer based spray and a solvent based spray?


This question is a little bit out of my realm of expertise, but traditionally lacquers and varnishes have resins suspended in a solvent other than water (water is a solvent, too), typically aromatic hydrocarbons.  The value of acrylic resin emulsions which are water based, is that they tend to be less toxic and easier to clean the tools after application. Beyond that, most folks use lacquer and varnish rather interchangeably, but there are other technical distinctions for those that want to be sticklers for accuracy. For example, a traditional varnish is made up of a resin that is kept in suspension by the addition of thinners and also contains drying oils that will help dry down properties, whereas a lacquer is made up of resin/solvent mixtures that also have dissolved nitrocellulose in them. The film forming properties of acrylic emulsions tend to be poorer at creating coatings with the highest gas and vapor barrier properties compared to resins, even the same acrylic resin, when suspended directly in a solvent rather than emulsified.  I'm sure others on this forum can add further nuances that account for various technical distinctions between acrylic emulsions, resin varnishes, and lacquers. Or google the topic. You will find out more that you ever wanted to know Cheesy

best,
Mark

The above is a good technical answer, the information I provide is more basic.   Wink

Most people are familiar with Shellac - this is a common form of lacquer which I recall thinking my father used to use on wood furniture.  Apparently nail polish uses it too.

http://en.wikipedia.org/wiki/Shellac

I suppose you could try Shellac on a canvas, but I have no idea what it would do or why it would be preferential.

Further, a solvent based varnish by my definition is a solution that uses mineral spirits or turpentine as a base for polymer and resin particles to be suspended in.

Through the curing process, the solvent evaporates (exposure to air) and the polymers bind with the resins to form a tight honeycomb surface which is both flexible and mar-able.

I know this, because I use this myself and have done so for over 5 years now.  

"Epoxy" finishes that use resins also can be used.  The effect is similar.

Mineral spirits mixed with oil based pigment have been used for centuries, we commonly call them oil paintings - more recent is the invention of polymers and the introduction of acrylic paintings which float polymers (plastic) in an aqueous base.  In both cases, the acrylic painting or oil painting are then varnished with a clear solvent based varnish to protect the painting underneath.  This is considered a truly archival method of painting because the varnish CAN be gently removed and reapplied if the surface layer is damaged (there is an isolation layer which separates the surface varnish from the paint layer).  Removing the varnish does not affect the surface layer

Water based solutions innovated in the last decade or so for use on giclee prints perform a similar function, but cannot be removed - so archival terminology in this context is a bit of a misnomer.  The print is really being coated with a permanent coating which bonds directly to the canvas, and it does enhance dmax, and also afford protection from fading, cracking and environmental pollution - but if the surface is damaged, repairing it is near impossible if not very very difficult.  ( Its easier to just print another one and coat it)

Shellac is not flexible and while we want a coating that will protect our canvases from fading, cracking and the environment, it must not be so rigid it is inflexible to movement or the varnish layer would crack.

Nowadays, people do all kinds of neat things with paper, canvas and photography and there are no "rules" - however, the danger in experimentation is that what may look good today doesn't stand the test of time.  What you put on top of your ink and paper may react and yellowing or flaking, or even cracking can happen in months.



Good luck

« Last Edit: December 14, 2013, 10:23:03 AM by Bullfrog » Logged
Pages: [1]   Top of Page
Print
Jump to:  

Ad
Ad
Ad