Re: Another PVA question
hi keith! i have exactly the same problem! i wrote a few mails about that earlier (header was somthing like: "caparol size gum woes". search for caparol and you should find them. you are using the gamblin size. that's a huge disappointment for me. i was using a pva-based product from a different company, called "caparol" and i hoped that switching from caparol to gamblin, this would eliminate the problem. marek said that he doesn't have this kind of adhesion problems with gamblin. and neither did loris btw. with a product similar to caparol. in my case the exposed and dried emulsion adheres well to the size when still DRY. as soon as it gets wet, it's very vulnerable. a few strokes with a wet bristle brush will brush it off. i've used dilutions from 1+1 (pva + water) to 1+20 and tried brush coating the size as well as immersion sizing with the higher dilutions. adhesion improves with the higher dilutions, but it never gets good enough. so, maybe this is more a problem of sizing technique than the kind of pva. i remember the video from one list member applying the pva size onto a platinum print. he brushed it in (with a foam roller) very vigorously and while drying it with a fan (iirc). maybe vigorously brushing the pvs into the paper fibers is the key? i hope to hear more about the problem, maybe we can solve it phritz Keith Gerling schrieb: OK, this is more troubling. It seems that when I try to hasten the development of a stubborn third layer using a brush, it also brushes off the underlying two layers. That's bad. I'm using Gamblin PVA size, undiluted. Never saw THAT happen with gelatin. Hardened layers were always impervious to anything. Am I doing something wrong here?. Arghh. My preliminary tests were very good and I went and bought 4 big bottles!
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