dryer temperature for RC

[veke]

I use rc papers and and olt-timer warming machine for fiber based papers is available. Yes, rc do get glossy when drying but for some reason my rc papers twirl, are not straight. How much temperature can I put on the "heater" not to damage rc papers? And do you have good answers why a rc paper becomes a curl when drying just like the fiber based ones? My theory is that the rc papers have some fiber in the background. Forte Polygrade-V resin coated, glossy is the mark, perhaps out of production nowadays, those are some years old but do give a nice print so why not use them. Many questions in one question, a great way to start the day...for you.

P.S. The device I could use is a Jumbo 160 mounting press with adjustable temperatures. I will try that. But would not want the rc prints to melt and damage the press. Any advice?

 

[AgX]

The PE layers, being thermoplasts, will soften beyond a certain temperature range to a degree that when cooling down they will set at a deformation that may have taken place.

The paper layer will react differently to heat than unprotected paper as either being dry or wetted only at the edges.

 

[Rick A]

I just air dry my rc prints, they flatten easily when mounted. If you want to speed dry them, either put them in a blotter book or in front of a fan on screens to dry both sides simultaniously.Drying rc prints in a heated dryer meant for fb prints could melt the pe layer and damage the dryer plates. Personally, I wouldn't even chance it on the lowest setting.

 

[AgX]

some ideas here:

(there was a url link here which no longer exists)

 

[BMbikerider]

If you need to hurry up the drying process with RC papers, you could do worse than use a hair dryer. I bought a cheap one which cost about £7 ($10) and after wiping the excess water off the front (Wide JOBO Squeegee) use the hair dryer on the high setting and this takes about 2-3 mins for a 16x12 print. I also use it for assessing the colour balance with RA4 paper because fresh out of the processing there is always a bluish cast in the shadows until it dries. Test strips take less than a minute to dry.

 

[veke]

thank you. So it seems that I will not use the warmer....One thing, the PE layers mentioned above, are those in fiber based or in resin coated, or in both? One thing came to mind, I wash the rc´s for 30 minutes although much less would be enough. Is 30 minutes too much?

 

[Rick A]

The pe(polyethelyne) layers are on rc coated paper not fiber base. You only need to wash rc paper for 2-3 minutes, prolonged exposure to water and chems causes the paper to delaminate.

 

[veke]

Test results:
- an almost dry print, didn´t feel wet in fingers
- place the print between two clean papers
- the device to 75 Celsius, keep the print there for about 30 sec
- first impression: a shock! The print was much more curved than in the beginning!
- place the print on the table and when cooling down it became flat. You can help the straightening with fingers a littel, not necessary
The print must not be wet, this is not a dryer it seems, cause I did that (of course) and the wet print got some fabrics from the papers.
This is not the final test report. Tomorrow I will see if I have any photo left, perhaps it vanishes during the night. But so far this seems my way to straighten out rc papers.

 

[AgX]

One thing, the PE layers mentioned above, are those in fiber based or in resin coated, or in both? One thing came to mind, I wash the rc´s for 30 minutes although much less would be enough. Is 30 minutes too much?

Well, ALL papers are fibre based (a very bad terminology has become standard).
So called fibre based papers are coated at one side with a baryta layer that mainly serves as reflective layer.
RC papers are coated on both sides with a thin PE layer, serving to protect the paper from the processing baths. The upper layer also serves as reflective layer.

 

[BMbikerider]

thank you. So it seems that I will not use the warmer....One thing, the PE layers mentioned above, are those in fiber based or in resin coated, or in both? One thing came to mind, I wash the rc´s for 30 minutes although much less would be enough. Is 30 minutes too much?

The RC paper neds no more than 10 mins in the wash with running water. Any longer then you run the risk of bleaching out the artificial whiteners and the print will look slightly degraded. Fibre based needs much, much longer but the use of a fixer eliminator bath will cut those times right down to about the same as RC papers.

 

[MattKing]

I just gently squeegee the RC prints on to the front of my refrigerator - image side out.

After a few minutes, they come off the refrigerator and go into a drying rack that started out as a holder rack for Vinyl LP records.

After about a further half hour, they are 95+% dry - depending on ambient temperature and humidity.

Here is the refrigerator about 5 years ago - during a postcard exchange.