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Author Topic: Canvas - poly-cotton vs cotton, whether to spray 1 side or both  (Read 9224 times)
shadowblade
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« on: February 26, 2014, 10:54:06 AM »
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I've previously been less than impressed with canvas prints - most of them have a thick gesso coating (which almost-but-not-quite masks the underlyiing canvas texture), on top of which an inkjet receiver layer is sprayed, giving them the thick appearance of a canvas for oil painting, but without the corresponding texture of oil paints on top of them, which is a strange appearance to me. Moreover, the gesso layer, which supports the inkjet and pigment layer, is liable to crack while stretching or flexing and to brittle with age.

Recently, however, I saw some prints made on Kernow's Kernewek range of inkjet-compatible canvases (as tested on Aardenberg) and am considering trying one of them. These lack the gesso layer - the fabric looks and feels like fine fabric, rather than canvas painted with layers of primer, are soaked rather than layered in inkjet coating and seem to give bright, saturated colours. It's hard to describe, but there's a 'lightness' to the fabric that suits smooth, textureless photographic output, as opposed to other canvasses whose thick layers of primer make them seem more suitable for oil or acrylic paints rather than photos.

I'm a bit at a loss on how to handle canvas, though, or even which one to select.

Kernewek's St Ives canvas is a 100% cotton, 400gsm canvas in a full Panama weave. Kernewek's Tresco canvas is a 50% polyester, 50% cotton blend - at 160gsm, it is a much lighter and finer weave. Both are OBA-free and seem to print very nicely, and I didn't see any evidence of cotton seeds in the 100% cotton canvas. Is there any technical/print quality/longevity reason to pick one over the other? Some people seem to swear by pure cotton, while others prefer poly-cotton, for reasons such as canvas sagging over time.

Secondly, how should a canvas print be sealed? Obviously the face of the print will need to be sealed, but what about the reverse side of the canvas? This will be inside the frame of a wrapped canvas, but still exposed to the atmosphere, allowing pollutants to penetrate the porous canvas and attack the pigments from the other side. Should both sides be sprayed, or just one side? If I spray the reverse, would the additional sealing protect the print better, or simply seal up solvents and other chemicals within the canvas, accelerating its deterioration?

Finally, is it possible or advisable to mat and frame a canvas print in a similar manner to a paper print, if the print looks good on canvas? If a canvas print - particularly one without the easily-cracked gesso layer - is to be displayed in this manner, would you suggest still coating it with Timeless Glossy/Matte or Eco Print Shield, or could you use something like Hahnemuhle Protective Spray instead, so as not to alter the surface appearance of the canvas?
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Justan
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« Reply #1 on: February 26, 2014, 11:22:19 AM »
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The media sounds interesting. My neighbor at a recent show did a technique called ďbatikĒ which is producing art works on cloth. And then he does lithographs or inkjet prints based on that. The works have a very unique and seductive texture, even when reproduced on paper. What you are describing sounds similar.

For finishing, personally I use Glamour 2 on the front and Miracle Muck to bond the back to an underlayment, but I donít use wraps. There is a lot of previous discussion on both of these materials.

Cotton would logically be stable the longest. There are a number of articles on the behavior of polyester and cotton cloth mixes over time. Use Mr. Google. As they are different materials, accordingly the reflective qualities change and they break down differently over time.

I have produced some canvas works that are not glued but rather taped to the underlayment using archival linen tape along the top edge along with traditional cotton fiber matting materials placed over the canvas edges. This works great for the most part but I have noticed that the canvas is more likely to bulge and move around than are paper based media using the same technique. This may be due to the fact that the exhibit works go in and out of a trailer during show cycles, but the other detail is that even coated canvas is nowhere near as stiff as paper. No one who has bought works done this way has made any negative comments, and that implies that in a typical environment this combination works fine.

The reason to coat the backside of canvas would be mostly to either bond it to something or to help protect it from decay. AFAIK, most put no coating on the back of gallery wraps, other than sometimes spray some distilled water to help shrink the canvas a bit.
« Last Edit: February 26, 2014, 11:24:38 AM by Justan » Logged

shadowblade
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« Reply #2 on: February 26, 2014, 11:40:50 AM »
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I'm not sure about cotton being the most stable. Unlike polyester, it absorbs water and, being composed of cellulose, it's also food for insects and fungi. Obviously a coating would slow this down, but polyester is entirely inedible.
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shadowblade
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« Reply #3 on: February 26, 2014, 12:52:43 PM »
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The range is also sold by Freestyle Photographic Supplies in the US, with different names for the same product, just to be confusing.

St Ives 400gsm = Monument Valley 400gsm (100% cotton, OBA-free)
Tresco 160gsm = Rushmore 160gsm (50/50 poly/cotton, OBA-free)
Marazion 260gsm = Sedona 260gsm (100% cotton, fire-retardant, OBA-free)
Newlyn 260gsm = Yosemite 260gsm (100% cotton, OBA-free)
Tintagel 140gsm = Yellowstone 140gsm (65% cotton, 35% poly, contains OBAs)

It looks like they produce a better Dmax than Lyve and Chromata White, too, as measured by the 'Max Black' patch in the Aardenburg files, using the same inkset.

I'm wondering, though - all the canvas media tested appear to have very weak blacks and saturation, at least going on the L value of the maximum black. Generally, they produce L values of 25-35 for the deepest blacks, as compared with 21 for Arches Watercolour (uncoated) and 19.5 for Hahnemuhle Photo Rag 308, using the same inkset. But canvas prints look neither undersaturated or lacking in contrast - why is that? Is it purely because of the gloss or matte spray universally applied to them? Does that mean that, when profiling an inkset for canvas prints, the profile has to be made using prints after they are sprayed, in order to end up with the correct colours?
« Last Edit: February 26, 2014, 01:04:34 PM by shadowblade » Logged
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« Reply #4 on: February 26, 2014, 07:03:29 PM »
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"But canvas prints look neither undersaturated or lacking in contrast - why is that? Is it purely because of the gloss or matte spray universally applied to them? Does that mean that, when profiling an inkset for canvas prints, the profile has to be made using prints after they are sprayed, in order to end up with the correct colours?"


I have also longed for an answer to this question.  Before or after varnish/coating profiling  for matt canvas.
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bill t.
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« Reply #5 on: February 26, 2014, 08:35:40 PM »
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Here are superimposed gamut hulls for Sunset Select canvas resulting from two profiles generated from the very same target, before and after coating with an extremely clear varnish.  Color hull is before, wireframe is after.

In practice, most of those volume gains are in areas that aren't important for most images.  The visual differences in print quality are far less than implied by the relative sizes of the gamut hulls.  The most consistently noticeable gain is that shadow details look richer and more textured with the "coated" profile.  But OTOH, I could probably post process the dark areas to get the same result with the uncoated profile.  For the most part I would be hard pressed to tell the difference between the two profiles applied to prints for most of my images.  I think the most admirable goal for a profile is just keeping the colors in line, and for that either of those profiles seems to be fine.

I have not done comparisons with profiles generated from matte or satin coatings.  I suspect the increases in dmax would be less due to the slightly hazy "matte" additives, as would overall gamut volume increases.  Has anybody done experiments?

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shadowblade
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« Reply #6 on: February 27, 2014, 12:31:12 AM »
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Here are superimposed gamut hulls for Sunset Select canvas resulting from two profiles generated from the very same target, before and after coating with an extremely clear varnish.  Color hull is before, wireframe is after.

In practice, most of those volume gains are in areas that aren't important for most images.  The visual differences in print quality are far less than implied by the relative sizes of the gamut hulls.  The most consistently noticeable gain is that shadow details look richer and more textured with the "coated" profile.  But OTOH, I could probably post process the dark areas to get the same result with the uncoated profile.  For the most part I would be hard pressed to tell the difference between the two profiles applied to prints for most of my images.  I think the most admirable goal for a profile is just keeping the colors in line, and for that either of those profiles seems to be fine.

I have not done comparisons with profiles generated from matte or satin coatings.  I suspect the increases in dmax would be less due to the slightly hazy "matte" additives, as would overall gamut volume increases.  Has anybody done experiments?

Given my penchant for highly-saturated landscapes, it looks like it may be worth me developing a RIP profile for the material as a whole, as well as ICC profiles for matte and glossy coatings to maximise the gamut and colour accuracy with each print.

Do you happen to have gamut charts for uncoated watercolour papers, by any chance? The Dmax of some (Arches Hot Press in particular) seems similar to that of many coated matte papers when using the same inkset; by using an ultra-wide-gamut inkset and a print heater to control dot gain, I'm hoping to exceed the performance of matte papers and K3/Lucia/Vivera inks, while printing on uncoated paper. But, as it is, I can't seem to find any baseline charts for comparison to see how much I would need to expand the gamut by.
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bill t.
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« Reply #7 on: February 27, 2014, 02:40:55 AM »
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You can create your own graphs from existing profiles using:

http://www.iccview.de

You will probably need to install the known-safe Cortona viewer.

The catches are:

1. iccview.de only accepts type 2 profiles, not type 4.  Breathing color uses type 2, but iirc Hahnemuehle uses type 4's.

2. While manufacturers' profiles are often pretty good, they are sometimes awful, as if for some different media.  So comparisons of unfamiliar media may embody a large error.

You can also compare profile graphs with X-rite's i1Profiler software, as the last step in the process after creating a new profile.  It also accepts type 4 profiles.  But only monochrome hulls are displayed, you have to know what colors go where in the lab colorspace.  There's a "demo" mode available for that software, but I don't know if it allows graph comparison.

FWIW, most glossy and coated papers have much better coverage in the -b to +a quadrant, where blues and violets and reds live.  Varnish coating greatly improves matte paper response in those color ranges, but for certain cool colors it's hard to beat true glossy media.

Uncoated watercolor will look a lot like oba-free matte canvas.  In fact, many matte media types are based on watercolor media ink handling.

And finally, comparing gamut hulls does provide a certain amount of information about what to expect from a particular media.  But you really have to do tests.  I have been testing glossy coated Pura Velvet for a few days.  While its gamut hull is nothing to write home about, it nevertheless has some pretty nice qualities and has given me a path into more subtle landscape interpretations that are still quite impressive in the color and tonality departments and capable competing with images printed on much flashier media.  Surprises are everywhere.
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shadowblade
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« Reply #8 on: February 27, 2014, 07:38:39 AM »
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You can create your own graphs from existing profiles using:

http://www.iccview.de

You will probably need to install the known-safe Cortona viewer.

The catches are:

1. iccview.de only accepts type 2 profiles, not type 4.  Breathing color uses type 2, but iirc Hahnemuehle uses type 4's.

2. While manufacturers' profiles are often pretty good, they are sometimes awful, as if for some different media.  So comparisons of unfamiliar media may embody a large error.

You can also compare profile graphs with X-rite's i1Profiler software, as the last step in the process after creating a new profile.  It also accepts type 4 profiles.  But only monochrome hulls are displayed, you have to know what colors go where in the lab colorspace.  There's a "demo" mode available for that software, but I don't know if it allows graph comparison.

FWIW, most glossy and coated papers have much better coverage in the -b to +a quadrant, where blues and violets and reds live.  Varnish coating greatly improves matte paper response in those color ranges, but for certain cool colors it's hard to beat true glossy media.

Uncoated watercolor will look a lot like oba-free matte canvas.  In fact, many matte media types are based on watercolor media ink handling.

And finally, comparing gamut hulls does provide a certain amount of information about what to expect from a particular media.  But you really have to do tests.  I have been testing glossy coated Pura Velvet for a few days.  While its gamut hull is nothing to write home about, it nevertheless has some pretty nice qualities and has given me a path into more subtle landscape interpretations that are still quite impressive in the color and tonality departments and capable competing with images printed on much flashier media.  Surprises are everywhere.

Thanks.

Unfortunately, my photographic style doesn't generally lend itself to subtle, low-saturation interpretations - they tend to be bold, dramatic and highly saturated (which is possibly why they seem to sell well in southern and eastern Europe, the Middle East, Asia and Latin America, but hardly at all in North America and the UK, where tastes seem to be more subdued...). Given that I'm trying to print on uncoated and receptor-infused (rather than receptor-coated) papers and canvases to maximise longevity, I need every bit of gamut I can get...

Any idea on the spraying of canvas prints? I'm not sure whether to spray just one side, or to spray both sides to completely seal the canvas (including trapping things in the canvas, if they're already there).
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Justan
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« Reply #9 on: February 27, 2014, 11:07:58 AM »
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Secondly, how should a canvas print be sealed? Obviously the face of the print will need to be sealed, but what about the reverse side of the canvas?

I donít have an answer to your question about coating the back of a work. Out of curiosity I did some research for about an hour but found no definitive or even direct answer to that. Perhaps Miracle Muck can be used for the back?

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Recently, however, I saw some prints made on Kernow's Kernewek range of inkjet-compatible canvases (as tested on Aardenberg) and am considering trying one of them. These lack the gesso layer - the fabric looks and feels like fine fabric, rather than canvas painted with layers of primer, are soaked rather than layered in inkjet coating and seem to give bright, saturated colours. It's hard to describe, but there's a 'lightness' to the fabric that suits smooth, textureless photographic output, as opposed to other canvasses whose thick layers of primer make them seem more suitable for oil or acrylic paints rather than photos.

I contacted Kerno about their Kernewek line to ask if can be treated with Glamour 2 and Miracle Muck. They offer samples and if it can be treated, Iíll definitely get a sample at least. Their media sounds similar to the batik treated works I saw at my neighbors booth recently. Very sexy stuff! Thanks for the tip.

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I'm not sure about cotton being the most stable. Unlike polyester, it absorbs water and, being composed of cellulose, it's also food for insects and fungi. Obviously a coating would slow this down, but polyester is entirely inedible.

Polyester stretches pretty easily and changes its reflective quality fairly quickly. I donít know if point 2 matters given that an ink receptor layer is part of the package. There are examples of cotton based fabrics dating back about 7,000 years with increasing samples as time moves forward.

According to some reading, a lot, even a majority of canvases historically were made of hemp or linen. Linen is often made from flax but may be made from cotton or other material according to: http://en.wikipedia.org/wiki/Linen. Interesting that the oldest examples of flax based linen are up to 1,000 years older than cotton.

I donít know if it is a good sales point to note cotton has only lasted up to about 7,000 years while linen can last up to 8,000 years. In contrast, people donít generally warm up to the word ďpolyester.Ē
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shadowblade
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« Reply #10 on: February 27, 2014, 11:20:27 AM »
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I donít have an answer to your question about coating the back of a work. Out of curiosity I did some research for about an hour but found no definitive or even direct answer to that. Perhaps Miracle Muck can be used for the back?

I couldn't find an answer either, but definitely wouldn't use Miracle Muck because it is acidic. Do Timeless or Glamour II outgas? If not, they could also be an option.

Epson does say, however, that their prints shouldn't be displayed in a humid environment unless they are 'coated with a solvent-based coating, front and back'. Not that you'd use a solvent-based coating to protect canvas, but I would have thought you could substitute 'impervious coating' for that.

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I contacted Kerno about their Kernewek line to ask if can be treated with Glamour 2 and Miracle Muck. They offer samples and if it can be treated, Iíll definitely get a sample at least. Their media sounds similar to the batik treated works I saw at my neighbors booth recently. Very sexy stuff! Thanks for the tip.

I contacted them about a few things too, mostly about sealing, protection and the nature of the surface coating ('infused' into the surface is a bit vague, but definitely implies something more than a simple coating). It would be interesting to take a piece of material, scrunch it up, sit on it, rub it against itself and generally do the sort of thing that would destroy a normal inkjet coating, before steaming it flat and running it through a printer to see how it prints, in order to test the durability of the inkjet 'coating'.

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Polyester stretches pretty easily and changes its reflective quality fairly quickly. I donít know if point 2 matters given that an ink receptor layer is part of the package. There are examples of cotton based fabrics dating back about 7,000 years with increasing samples as time moves forward.

I'm not talking about ease of stretching - I'm talking about dimensional stability when exposed to changes in relative humidity. Polyester is more dimensionally stable in that regard - there are many reports of canvas prints sagging after being stretched.. Then again, if the canvas is coated front and back with Timeless Matte/Glossy for protection against moisture and to impart a surface quality, that may not be an issue.

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According to some reading, a lot, even a majority of canvases historically were made of hemp or linen. Linen is often made from flax but may be made from cotton or other material according to: http://en.wikipedia.org/wiki/Linen. Interesting that the oldest examples of flax based linen are up to 1,000 years older than cotton.

I donít know if it is a good sales point to note cotton has only lasted up to about 7,000 years while linen can last up to 8,000 years. In contrast, people donít generally warm up to the word ďpolyester.Ē

Maybe linen just happened to be used before cotton...
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Some Guy
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« Reply #11 on: February 27, 2014, 11:38:16 AM »
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Some canvas products seem to have a finer weave than others.  With the amount of ink receptive layers, it might even appear to be absent (Inkpress Canvas comes to mind which looks more like a cotton weave than a coarse canvas.).

I have tried some of the Crane canvas and not too crazy about it as it seems dull and flat.  The BC Silverado (A metallic, but more like a opalescent cream to me) suffers from head strikes (It curls up badly on the side.) on my printer and ink runs a bit on the hard surface so there is some bleeding with it - and, okay, it smells bad too!

My favorite so far for a nice black and showing a decent canvas surface is Premier Art Canvas, but it has OBA too so the white is obvious and seems to glow in dark rooms.  I spray with their Premier lacquer so it seems to enhance the black and protect the surface as well.  My framer mounts them to some flat substrate somehow that may seal the back (Don't know?), along with 30 seconds in a heat press, prior to framing them with a suede-liner mat inside a frame.  Cost is about $450 per frame doing it that way.

SG
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shadowblade
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« Reply #12 on: February 27, 2014, 11:59:41 AM »
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Some canvas products seem to have a finer weave than others.  With the amount of ink receptive layers, it might even appear to be absent (Inkpress Canvas comes to mind which looks more like a cotton weave than a coarse canvas.).

I have tried some of the Crane canvas and not too crazy about it as it seems dull and flat.  The BC Silverado (A metallic, but more like a opalescent cream to me) suffers from head strikes (It curls up badly on the side.) on my printer and ink runs a bit on the hard surface so there is some bleeding with it - and, okay, it smells bad too!

My favorite so far for a nice black and showing a decent canvas surface is Premier Art Canvas, but it has OBA too so the white is obvious and seems to glow in dark rooms.  I spray with their Premier lacquer so it seems to enhance the black and protect the surface as well.  My framer mounts them to some flat substrate somehow that may seal the back (Don't know?), along with 30 seconds in a heat press, prior to framing them with a suede-liner mat inside a frame.  Cost is about $450 per frame doing it that way.

SG


The thick, white substance that obscures the weave in most inkjet canvases isn't the receptive layer - it's a kind of gesso. The receptive layer itself is a thin layer on top of the gesso. The canvas I'm talking about here doesn't have the gesso layer, and the documentation seems to imply that the receptive layer is soaked into the canvas, surrounding the individual threads, rather than just applied as a layer on top of of the fabric, that can easily rub or flake off as the canvas flexes and as the inkjet layer embrittles over time.
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« Reply #13 on: February 27, 2014, 12:07:24 PM »
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I couldn't find an answer either, but definitely wouldn't use Miracle Muck because it is acidic.

According to the manufacturer of Muck:

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The short answer to this question is that Miracle Muck is slightly acidic as it pours from the jug.  The more complete answer, and what really counts to most users, is a little more complicated than this adhesiveís ph in itís liquid form.  Judging the usefulness of an adhesive based purely on its liquid ph misses the mark for a couple of reasons.  First of all, almost any adhesive can have its ph chemically raised or lowered, and in most cases this would tend to reduce its effectiveness as an adhesive.  What most people really want to know when they ask about the ph of Muck, is ďwhat effect will this adhesive have on the other components of this framing package?Ē  The answer to this question is that once Muck has dried, it will be essentially inert and have no negative impact on the other components.  But there is more to it than that, because as it dries Miracle Muck becomes an effective barrier that will serve to inhibit the migration of acidity from other components it is applied to, such as wooden liner stock , for example.  Since the most common way acidity moves within the framing package is when the components absorb moisture from the environment it is nice to know that once it has cured (48-72 hrs after application) Muck is nearly impervious to moisture.
http://www.raphaelstoday.com/Pages/MiracleMuck.aspx

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It would be interesting to take a piece of material, scrunch it up, sit on it, rub it against itself and generally do the sort of thing that would destroy a normal inkjet coating, before steaming it flat and running it through a printer to see how it prints, in order to test the durability of the inkjet 'coating'.

I donít know if that would be a useful test. The coatingís durability would be better testing by exposure to UV to measure itís stability over time. This is outta my league but here is an article http://en.wikipedia.org/wiki/UV_degradation There is some UV resistant polyester available.

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I'm not talking about ease of stretching - I'm talking about dimensional stability when exposed to changes in relative humidity. Polyester is more dimensionally stable in that regard - there are many reports of canvas prints sagging after being stretched..

Apology for an ambiguity. I wasnít making reference on ease of stretching but rather the tendency of the media to stretch over time. Polyester is elastic and that diminishes over time and the fibers relax, causing it to sag. Think of old polyester clothing as comparison. I agree that typical stretched canvas will also sag over time and due to humidity. I'm in the high humidity northwest USA (aka "northwet") The tendency of gallery wraps to sag is one of the many reasons I donít use this mounting technique.

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Maybe linen just happened to be used before cotton...

That is possible. I donít know. The point I was implying is that both linen and cotton are long lived, natural fibers. In contrast, most consider polyester as a low cost alternative. As such it may not present very well when mentioned in sales talks.
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shadowblade
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« Reply #14 on: March 01, 2014, 02:23:54 AM »
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According to the manufacturer of Muck:
 http://www.raphaelstoday.com/Pages/MiracleMuck.aspx

I donít know if that would be a useful test. The coatingís durability would be better testing by exposure to UV to measure itís stability over time. This is outta my league but here is an article http://en.wikipedia.org/wiki/UV_degradation There is some UV resistant polyester available.

Apology for an ambiguity. I wasnít making reference on ease of stretching but rather the tendency of the media to stretch over time. Polyester is elastic and that diminishes over time and the fibers relax, causing it to sag. Think of old polyester clothing as comparison. I agree that typical stretched canvas will also sag over time and due to humidity. I'm in the high humidity northwest USA (aka "northwet") The tendency of gallery wraps to sag is one of the many reasons I donít use this mounting technique.

Polyester is certainly more elastic than cotton, becoming less elastic over time, but how does that translate to sagging? Generally, loss of elasticity simply means that the material becomes more rigid and stiff, rather than loosening and sagging. Polyester is much more dimensionally-stable fabric than cotton, not changing much whether conditions are warm or cold, dry or humid - stretched cotton canvases tend to sag in cold, dry conditions and tighten up again in warm, more humid conditions, while poly-cotton and pure polyester fabrics don't.

Both polyester and cotton will embrittle over time, though, which may make mounting rather than stretching a better option. The use of adhesives comes with its own problems, though - I've yet to find someone who will wet-mount a print (whether paper or canvas) to aluminium or Dibond using conservation-grade adhesives (e.g. Lascaux 303/360/498)

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That is possible. I donít know. The point I was implying is that both linen and cotton are long lived, natural fibers. In contrast, most consider polyester as a low cost alternative. As such it may not present very well when mentioned in sales talks.

I don't know - polyester has better UV and water resistance than cotton (hence its use in sailcloth, although it has been replaced by other fibres where tensile strength is more important than durability) and isn't biologically active. It also has better UV resistance than polypropylene and nylon - two other synthetic fibres commonly used to make fabric. Sure, cotton has survived for a long time in cool, dry and dark places (inside millennium-old Ethiopian rock-hewn churches, for example), but I doubt it is nearly as durable in conditions of higher humidity or temperature (paper is somewhat different, since it is sized).

The thing is, the poly/cotton canvas here is 160gsm, vs 400gsm for the cotton. Is 160gsm too thin for long-term survival when stretched?
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« Reply #15 on: March 01, 2014, 09:19:55 AM »
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Polyester is certainly more elastic than cotton, becoming less elastic over time, but how does that translate to sagging?

Iím not a chemist so donít have a direct answer. As a practical matter, as the material ages the elastic properties outgas or become inert, and the fibers stretch under their own weight. But Iíll grant that being 100% synthetic, itís possible to stabilize the media for nearly any application. The detail is that I could not find anything to support or deny that is actually done. Have you?

Some have tested some polyester types and found them stable for up to 80 years in a museum environment http://www.vam.ac.uk/content/journals/conservation-journal/issue-44/how-fast-do-polyester-fabrics-age-in-the-museum-environment/

In contrast, many point out that linen, cotton and cotton rag has been proven stable for hundreds of years around the world in museum environments and elsewhere.

I could not find anything to support archival polyesters except in the form of print sleeves and due to this donít have a direct answer.

Aesthetically, polyester has about as much appeal in the arena of archival media as ďpink slimeĒ does in food production. Polyester does not resonate favorably. One could side step that and simply refer to the media as being archivalÖ..if there is some factual basis that it isÖ

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Sure, cotton has survived for a long time in cool, dry and dark places (inside millennium-old Ethiopian rock-hewn churches, for example), but I doubt it is nearly as durable in conditions of higher humidity or temperature (paper is somewhat different, since it is sized).

Huh? Your doubts are not well founded. Hemp started use in canvas around 3,000 BC. Many examples of hemp based canvas exist. Linen based canvas media has been in use for canvas in art starting around the 15th century. Thousands of examples exist. Cotton came into use at about that time because itís less expensive to produce.http://en.wikipedia.org/wiki/Oil_painting . As I noted previously, there are examples of both linen media going back about 7,000 years and cotton media going back 6,000 years. Everything else aside, that is a lot of institutional memory to overcome.

I did hear back from Kernow Coatings and they say their USA distributor is http://www.freestylephoto.biz. The person at Kernow I wrote to replied he was familiar with Glamour 2 and Muck but had not used them with Kernow products. Hmmm. I havenít had time to contact freestylephoto as Iíve been swamped with orders from my last show. I do think Iíll test some of the Kernow St Ives Fine Art (100% cotton) as it may look great with some of my flower and possibly farm land subjects. Evidently it does not sell under the Kernow name at freestylephoto.

Off to my studio. I have about 70 feet of canvas works to coat.
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shadowblade
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« Reply #16 on: March 02, 2014, 09:59:18 AM »
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Iím not a chemist so donít have a direct answer. As a practical matter, as the material ages the elastic properties outgas or become inert, and the fibers stretch under their own weight. But Iíll grant that being 100% synthetic, itís possible to stabilize the media for nearly any application. The detail is that I could not find anything to support or deny that is actually done. Have you?

Some have tested some polyester types and found them stable for up to 80 years in a museum environment http://www.vam.ac.uk/content/journals/conservation-journal/issue-44/how-fast-do-polyester-fabrics-age-in-the-museum-environment/

In contrast, many point out that linen, cotton and cotton rag has been proven stable for hundreds of years around the world in museum environments and elsewhere.

It also becomes incredibly brittle with age and loses tensile strength (tensile strength being particularly relevant in a stretched product). Cotton was rarely used in artistic canvases until the end of the 19th century, when stronger linen and hemp canvases became more expensive.

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I could not find anything to support archival polyesters except in the form of print sleeves and due to this donít have a direct answer.

Polyester has a much simpler chemistry and structure in comparison to cotton and other natural fibres, being composed entirely of a single material. It's much easier to test something like this for longevity than to test natural fibres.

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Aesthetically, polyester has about as much appeal in the arena of archival media as ďpink slimeĒ does in food production. Polyester does not resonate favorably. One could side step that and simply refer to the media as being archivalÖ..if there is some factual basis that it isÖ

I'd definitely agree on this - but only at this point in time.

But, 800 years ago, oil paintings were also regarded this way (tempera being regarded as better). 500 years ago, paintings on canvas and paper were regarded this way (rigid wooden panels, as well as walls of buildings, being preferred). 100 years ago, photographs were regarded this way (paintings being preferred).

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Huh? Your doubts are not well founded. Hemp started use in canvas around 3,000 BC. Many examples of hemp based canvas exist. Linen based canvas media has been in use for canvas in art starting around the 15th century. Thousands of examples exist. Cotton came into use at about that time because itís less expensive to produce.http://en.wikipedia.org/wiki/Oil_painting . As I noted previously, there are examples of both linen media going back about 7,000 years and cotton media going back 6,000 years. Everything else aside, that is a lot of institutional memory to overcome.

And, among the thousands of surviving pieces, there are millions that did not survive - eaten by silverfish, embrittled with age and reduced to dust, destroyed by mould or other fungi...

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I did hear back from Kernow Coatings and they say their USA distributor is http://www.freestylephoto.biz. The person at Kernow I wrote to replied he was familiar with Glamour 2 and Muck but had not used them with Kernow products. Hmmm. I havenít had time to contact freestylephoto as Iíve been swamped with orders from my last show. I do think Iíll test some of the Kernow St Ives Fine Art (100% cotton) as it may look great with some of my flower and possibly farm land subjects. Evidently it does not sell under the Kernow name at freestylephoto.

I haven't heard back yet. The other thing I was wondering is whether the canvas uses MK or PK inks - important if you're using custom inksets, or black-and-white inksets like Cone and MIS.
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shadowblade
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« Reply #17 on: April 06, 2014, 07:18:08 AM »
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I did hear back from Kernow Coatings and they say their USA distributor is http://www.freestylephoto.biz. The person at Kernow I wrote to replied he was familiar with Glamour 2 and Muck but had not used them with Kernow products. Hmmm. I havenít had time to contact freestylephoto as Iíve been swamped with orders from my last show. I do think Iíll test some of the Kernow St Ives Fine Art (100% cotton) as it may look great with some of my flower and possibly farm land subjects. Evidently it does not sell under the Kernow name at freestylephoto.


Have you managed to try it yet?
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Justan
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« Reply #18 on: April 06, 2014, 10:49:31 AM »
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I received 2 sample rolls but have not cracked them out of the shipping box just yet.
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shadowblade
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« Reply #19 on: April 09, 2014, 01:44:15 AM »
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Please post when you've managed to try them. I'd be very interested to see how/if they work with Timeless.
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