any way to produce UNCURLED carbon paper?

[q_x]

Hi there!
Me again.

I've been googlin this for a week. If there was some post here (or somewhere else) - please give me a link if you can.
I know this is a common issue, but...
Is there any way to produce uncurled carbon paper? Is making curtain coater the only way? (I've seen the patents, looks promising)

What I was trying:
Coating both pre-soaked and dry papers.
pouring pigmented gelatin solution and spreading with fingers or with rod (fingers was better), with or without the frame.
PE-like coating blade surrogate (wooden [ bracket with rod in place of the blade), works fine and gives even coats, but paper curls.
or with serigraph/silkscreen V-shaped aluminum coater
The coater looks like a aluminum gutter or a half-pipe with closed ends. I poured liquid coat into, pressed it onto a paper and moved all down - this way coating the paper. It was something like 75% waste of of the coating solution. The paper remained *almost* uncurled, but the coat was to thin, so I think with thicker coat it will be more curled.

I've also tried to pour coat directly onto the glass and put wet paper onto it. After drying I was unable to separate the tissue with support and glass - the sandwich is taking long bath now.

I used papers:
One-side coated offset printing paper (used for calendars), something like 150 g/m2
Fabriano Accademia 120g/m2
ordinary white office paper 80g/m2

Coats have 7-20% of edible gelatin, pigment, sugar, and sometimes soap, thickness varying from 0,5 to 2mm.

And paper after drying was always curled. Less or more, but always. If less - It was left to flatten under heavy load. If cracks while trying to fit it in there - it goes to trash.

Any hints to make the paper flat?

I know one good way: Buy myself 10 plexi, PVC or glass sheets (my wallet say it is maximum for now), but it is not cheap, not easy to store or wash, and allows me to go with small runs only. Using old LF Photo sheets is not a good way for me (don't have it), but maybe inkjet/laser transparencies will work?

Next thing I'm going to try will be 0,3-0,5 mm thick 50% gelatin layer - almost like a paste - and coating dry paper with PE's blade surrogate.

Cheers,
Luke

 

[Whiteymorange]

I'm afraid I don't know the process, so I may be talking "through my hat" as my Dad used to say, but one of the ways to compensate for curl when coating paper for other processes it to coat the other side as well. Just as painting the back of a wooden panel prior to painting the front keeps warping down, the coating of both sides of the paper can compensate for curl. Can you use un-pigmented gelatin on the back, or would the next steps of the carbon process be compromised by that?

 

[q_x]

This may be a good idea. I'll try to dip-in the paper, so Ill get both sides coated at once.
Don't know how to dry such a coat, I must probably rotate the paper while waiting until gelatin sets, and next hang it to dry.
Worth trying, so i'll try.
Thanks

 

[rwyoung]

Disclaimer : never done carbon printing but I've been fooling around a lot with cyanotypes, salt prints and now gum bichromate so there is a lot of wet paper time involved...

I've spritzed the back side of a sheet of watercolor before coating the front. Just some distilled water in a clean spray bottle. Made the back just damp and it seems like I didn't get as much curl after rod coating the front pretty heavy with cyanotype solution. YMMV.

I've often seen it recommended for various alt processes to steam or damp the back side with a sponge before coating.

One other thought, you could try soaking the paper for a bit in hot water (as hot as your hands can stand) in a clean tray. Then hang to dry. This pre-shrinks the paper prior to adding any other sizing. Maybe it would help. Maybe it would make a mess. Maybe it makes no difference with carbon.

With some luck, Sandy King will spy this thread and chime in.

 

[q_x]

Oh, I see you like Solaris!
Ive been trying to coat both side wet papers. Results failure.
Carbon tissue is much "stronger" (as in "strong man") and thicker, than gum-bichromate layer. I'll try to shrink paper in hot water. Just in case.
Thanks.

 

[Dave Wooten]

Yupo

get it at the art store-for tissue
fix out rc paper for the image

See Sandy King's presentation on the Alternative Process site.

 

[q_x]

Dave, I live in Poland an I'm getting *tired* with it. We have some synthetic papers, but no heavyweight affordable option. Buying glass or white plastic (2mm thick PVC) sheets can be cheaper solution in Poland. But I'm not experienced enough to know if such water-resistant surface, flat (glass) or with delicate grain (PVC) be good as a carbon tissue support material. So here is the next question. AFAIK PVC cannot be heated over 60-70C.
This might be a good way for me
Thanks

 

[Dave Wooten]

www.yupo.com I think they have distribution in Europe. They can be contacted at the mentioned website. We used this product at Sandy King's carbon class at the Photographers Formulary, it is the best.

 

[Photo Engineer]

I have to second Dave's recommendation of Yupo. Sandy King introduced me to it and it does a fine job.

I also see that you are using plain paper. It has a tendacy to curl, but curls less as you go up in weight. It also can curl less if you add a gelatin coating to the back of the paper.

PE

 

[q_x]

Thank you
First of all - I've lied a little. There is a Yupo distributor in Poland (Papyrus, also in other parts of Europe). One, and only one. They will sell minimal quantity of 125 sheets of 1000x700 mm (not affordable for me).
There is a little - but always - chance to get the Yupo in shop somewhere near. I'll ask tomorrow. What is the minimal g/m2 value for Yupo to use for carbon?
If 2mm PVC "looking like white cardboard, acting like plexi" (supposly much more durable than yupo) will be the same price - what would you recommend? And can glass be used?
Cheers and thanks again,
Luke

 

[Colin Graham]

For tissues, try upping the sugar in the pigmented gelatin a little or adding some glycerin to it. I use 3 mil drafting mylar for the tissue support, which is very thin and doesn't curl as it dries. I also press the tissues in a yupo binder after the tissues are thoroghly dry to flatten the further. I tried yupo for the support but I couldn't get it to lay flat for coating without it 'popping' in the center and ruining the uniformity of the tissue.

If you're simply having problems keeping the tissue support flat during coating, mist the work surface, then firmly squeegee the support to it before pouring the pigmented gelatin.


Also- here is a wonderful carbon printing forum-[URL="http://bostick-sullivan.invisionzone.com/index.php?showforum=2"]http://bostick-sullivan.invisionzone.com/index.php?[/URL]

 

[q_x]

Thanks Colin! The link - very interesting!
Paper curls when dry, not while coating. Making even coats is not so big problem if I'm doing this fast. I'm adding lots of sugar (about 1/5 to the gelatin). I'm also squeezing the tissues when dry - once before and once after sensitizing it.

Meantime I've made some progress

Yupo wasn't in the shop. "No sintetic papers, cotton only".

I've tried once more with the heavyweight paper and 0,75 mm thick 25% gelatin - it was good, almost acceptable.

And here is the bomb:
I've tried 2mm thick white "cardboardish" plastic sheet (it is sometime used to cut the letters in, or as a banner support with some print/cut-out glued on it). It was easy to coat it with satisfying coat. After drying (no heating, just waiting the 20 hours) the gelatin tissue and the supporting sheet can be easily separated. First time I've seen such a thing! I can take the tissue and with a little help of water - glue it where I want - with the bubbleless, dust-free side to the support.

Thanks all for support.

Cheers,
Luke

 

[Photo Engineer]

Luke;

The plastic is not subbed. All plastics repel gelatin in water and so when dry, they can be separated. Yupo and all conventional film supports are subbed to prevent separation when dry or wet.

PE

 

[Colin Graham]

Well, I certainly gave up too easy on Yupo- I tried it again last night and it works quite well. Lays flat while coating and the rigidity of the plastic helps the tissues to dry much flatter than the mylar.

I forgot to mention to be careful with the glycerin if you do use it- a little goes along way. If you're in a humid climate probably better to avoid it altogether, the tissue may never dry completely. I tried using 10ml/liter here (western Washington) and the tissue was still sticking to the negative after 3 days.

 

[Jim Fitzgerald]

I recently took a carbon workshop with Vaughn up in Hayward,Ca. He showed us a trick. After you pour your tissue and it has set up a bit transfer it to a piece of cardboard and put a bit of the leftover glop on each corner and push a pin in the corner to hold it flat. Dry hanging with a fan on it. His tissue that we used at the workshop was nice and flat.

Jim

 

[Photo Engineer]

I believe that sorbitol can be used in place of glycerine and it has less tendancy to dry tacky, but it still can if you use too much.

PE

 

[sanking]

I use Yupo as the support for carbon tissue. It is the single best support I know of, and if you use the light weight material it is reasonably economical. Most carbon tissues will curl when dry unless you store them flat as soon as the tissue is dry. I dry my tissue oin screens and as soon as it is dry I transfer it to a holding box where it is kept flat. If you leave the tissue lying around, or store it in a roll, it will curl severely, especially in dry climates. Glycerine should be avoided except in very dry climates as tissue that contains cglycerine can be very slow drying after sensitizing.

Sandy King

 

[q_x]

Thank you all! You are very helpfull and supportive.

I don't use glycerine. It is worm and humid now (25C, raining). I add only sugar (and soap in some rare experiments).

I've made myself magnetic stir plate - nice and cheap tool. But how to heatglass on this in el-cheapo way?

PE: In fact: separated gelatin tissue is almost useless.

Offtopic: have you tried to use glass to make your coating blades? AFAIK glass is much easyier to work with it than with metal when high precision is a must.

Jim: I've tried to hold the paper (120g Fabriano Accademia) with clamps. It is usable, but curled at the edges. And it is torn at one corner (huge forces while drying did this). I'll try pinning onto cardboard.

Sandy: I store the tissues flat under heavy weight. I've managed to made some of them uncurled enough to be
usable in most areas (edges and corners are stubborn, but maybe this is the way it should be). I will look for Yupo or some surrogate. I live in 500k city, I've tried to find yupo in the most popular shop here - no chance. I'll try in other shops. Perhaps I'll ask some of my friends to buy it on holidays. Or I'll buy glass. Should be cheaper (not cheap :/ ) and usable too. Maybe I'm patient enough to coat very few sheets at once.

Thanks for helping. I'm going to shut up and try all the methods mentioned above. I'll post results after ending.
Cheers,
Luke

 

[Vaughn]

I coat thickly onto used litho film (.004" thick), then use push-pins to attach it to a piece of cardboard to dry. I use a little of the excess gelatin mixture under each corner to "cement" the tissue to the cardboard. The tissue can not curl. I brush (spirit) sensitize the tissue right on the cardboard and dry for an hour or two with a fan. The dried, sensitized tissue does not curl when removed from the cardboard.

Vaughn

PS...sorry did not notice that there was a second page of responses. I find the edges curling up a bit to very helpful when spirit sensitizing -- the curl keeps the sensitizing solution on the tissue when one is brushing it around. And it is not necessary to evenly sensitize the edge -- since there will be no image there as it is the "safe edge" -- I have a 1/2", or 12mm, safe edge.

I have some Yupo that I bought many months ago -- I'll have to give it a try one of these days! I imagine that the Yupo would act very similar to the used litho film since both are non-pourous, non-paper material.

 

[q_x]

Any LF film - I'll try it as soon, as I find it. I've lost few 30x40 cm sheets somewhere.


Thanks for helping me. It is good to find helpful people. I have some background in gum bichromate printing (and working with paper in general). This tissues are still really big quest, adventure and challenge for me.

Here is the summary of this whole action.

What was my goals:
To start making cheap and really high quality custom carbon tissues.
Do this in one, fast, non-complicated way for both small (postcard) and large (A3 and bigger) formats.
Do this without making too much mess in my new small flat.
Coating several tissues at one time.

Not all actually are of equal importance.

What I've been testing:

Two papers:
Fabriano Accademia 120g, acid free thin sketch paper. It is thin, so it was good indicator if the method is good.
One side coated offset printing paper 170-200g, standard paper used eg. to print postcards.
Hot-bathed or simply wet when needed

Edible gelatin (mostly with bloom 150-170, other was weaker), various artist's pigments in powder form (from Kremer).

And some methods - and the result (after coating, drying, wetting - in place of sensitizing - and drying again):
1. Coating paper with fingers or bar within frame - lots of mess and things to wash, paper had uneven coat and was curled after this; maybe this is the good way, but not for me or not in the moment or not with the papers.
2. Coating paper (edge to edge) with fingers - less messy, paper almost 100% usable (curled edges).
3. Coating paper with crude PE-style blade - thicker paper is usable when coated with strong gelatin solution (25-30%), but with strong solution bubbles and dust are serious problem. It is possible to coat only one tissue at a time. After this I had to wash and dry the blade.
4. Coating paper with silkscreen half-pipe coating tool - very messy, it was hard to control the coating. Good results, but most of gelatin solution was wasted
5. Coating PE-LD sheet (2mm thick white matte plastic) with fingers (with or without putting paper on this) - the result was always tissue separated from support. Unusable unless I want to produce carbon "instant pasta". Paper curled taking gelatin with it.
6. Coating glass with fingers - very good. Haven't tried to use this to print something - I don't want to use dichromate in old flat, but should be OK.
7. Coating glass with fingers and cover it with paper - it is hard to avoid air bubbles within gelatin and paper with larger sheets of paper (or destroying coat while getting rid of the bubbles). I was also unable to separate tissue and glass after drying.
8. Coating plexi with fingers - act as glass if the gelatin is sweet enough and stronger than 10% and surface is clean. Traces of lipids/fat are hard to cover with gelatin
9. Coating plexi with fingers and cover it with paper - after drying it is easy to lift the gelatin and separate tissue and plexi. Very good for smaller tissues (postcard size).
10. Methods with covering back of paper with gelatin - not so good results for me. When paper was not flat - I was unable to coat it on the other side. When it was flat before coating - it was curled after. Too much effort for the simple thing. I'll try this with sized paper - as for gum bichromate.
Dip-in the paper - unable to dry even layer of gelatin. I will try this in winter, gelatin will set within seconds.

Conclusions/thoughts/ideas for now:
Soft toilet paper is good weapon against big bubbles.
Big syringe is my big friend.
YUPO is unavailable in Poland, it is easier to see polar bear than YUPO in shops here.
It is very hard to coat thin paper (but isn't using thick paper a waste?)
Using glass or plexi (but not PE-LD) in place of paper is cheaper, both can be used hundreds of times. Plexi is easy to scratch and not so-so in hot water, glass is easy to break. Both are available.

I think after moving to the new flat I'll save some money and buy few sheets of glass between a4 and a3 size (I have trays 45x32cm) and make lightproof rack'o'cabinet to dry it with blown-in dust-free air. I think computer fan powered with old cellphone charger and some muslin, nylon or gauze filter will be working good enough. Nice if top of the cabinet also could be used as coating and printing table.

Cheers

 

[Vaughn]

Even coatings are not required since one exposes downward through the gelatin -- how much unexposed gelatin is under the exposed gelatin does not matter (as long as there is some unexposed gelatin).

I tried using .007" film stock a long time ago. I had trouble getting good contact in the printing frame -- the support was too stiff. But more pressure (or a vacuum frame) might allow it to work.

Coat as large of a tisse as you can -- then once it is dry, cut it down to the sizes you need.

Your coating method #2 is the one I use -- I like getting my finger into the black glop!

If you see a polar bear in Poland, he'll probably have some Yupo in his backpack.

Have fun!

Vaughn

 

[Marco B]

I haven't done carbon printing, but have used liquid photo emulsion with similar issues. One solution is to pre-soak the paper and use watercolor tape to tape it down and leave it to dry before coating it. It will give you perfectly flat coated papers, however you must be able to safely (in the dark) dry these taped down coated papers.

For that, I have devised a light tight coated paper drying box based on a developer tray, which I have described in full here:

http://www.boeringa.demon.nl/menu_technic_paperdryingbox.htm

Have a look, it might be of help.

 

[q_x]

Vaughn - thanks for feedback. Actually using "waterproof" supports seems to be worth experimenting. I will be testing glass today once more. Crossing my fingers.

Marco - I know the method. I've been doing *lots* of graphics (mostly aquatint) drying paper like this. We also used wood glue (looking like high-fat cream) with some water and newspapers paper or some drafts, sketches or paper scraps to glue and dry wet prints (in place of the watercolour tape - it is hard to get it and it is not cheap). Only problem I see here is drying paper after soaking in dichromate - I don't want to have dichromate-soaked wood in the place I will be living. But this is a minor issue.
Carbon printing is the cheap way for me, and this is all this noise for.
I've seen the drying cabinet. Nice and inspiring

Thanks

 

[Vaughn]

Drying does take a little longer with waterproof supports -- but they usually are reusable. Carbon printing is only expensive in relation to one's time...but you get what you pay for with your time! good luck!

Vaughn

 

[sanking]

If you have not already seen it have a look at my article on carbon printing here, http://www.alternativephotography.com/articles/art110.html

The method I use for coating is very efficient, and is only marginally more complicated than just pouring the glop on the paper and evening it by hand. But it gives a much smoother tissue, one with no bubbles or surface debris, assuming you dry in clean dust free room

Plastic supports (RC papers, film, Yupo) are much better than paper in my opinion because papers sometimes contain chemicals that interfere with the carbon process in one way or another. However, whatever you use be sure to flatten the carbon tissue as soon as it is dry. If you just leave it open to the air the tissue on any support, paper or plastic, will continue to dry out and develop a very severe curve that will make it very difficult to use.

Sandy King

Vaughn - thanks for feedback. Actually using "waterproof" supports seems to be worth experimenting. I will be testing glass today once more. Crossing my fingers.

Marco - I know the method. I've been doing *lots* of graphics (mostly aquatint) drying paper like this. We also used wood glue (looking like high-fat cream) with some water and newspapers paper or some drafts, sketches or paper scraps to glue and dry wet prints (in place of the watercolour tape - it is hard to get it and it is not cheap). Only problem I see here is drying paper after soaking in dichromate - I don't want to have dichromate-soaked wood in the place I will be living. But this is a minor issue.
Carbon printing is the cheap way for me, and this is all this noise for.
I've seen the drying cabinet. Nice and inspiring

Thanks