Re: Gelatin-polymer blend (was Re: Gesso sizing)

From: Marek Matusz ^lt;marekmatusz@hotmail.com>
Date: 01/21/06-10:32:48 AM Z
Message-id: <BAY101-F16E586E7321AE7BE06FCCDBB1E0@phx.gbl>

Katharine,
I have used acrylic medium (20% in a 6% gelatine). Medium dies notcontain
any pigment, no reason to worry about titabium dioxide bleaching. Inded very
durble sieze for gum.
Marek, Houston

>From: Katharine Thayer <kthayer@pacifier.com>
>Reply-To: alt-photo-process-l@sask.usask.ca
>To: alt-photo-process-l@sask.usask.ca
>Subject: Re: Gelatin-polymer blend (was Re: Gesso sizing)
>Date: Fri, 20 Jan 2006 06:48:32 -0800
>
>What's the difference between transparent acrylic gesso and acrylic
>medium?
>
>I did try mixing gelatin and acrylic medium once and wasn't happy with the
>results, but it was only that one try. As I recall, the image broke up and
>flaked off, which suggests maybe I put too much acrylic in it.
>
>One of the reasons I haven't used the gelatin-gesso size for exhibition
>prints is that I've never been sure about the permanence of this
>combination, although it is my favorite surface to print on. Ryuji's
>cautions about the titanium dioxide do give me pause. Perhaps someone who
>lives where the sun actually shines could size some paper with this
>combination, print a gum print on it, and put it in ta south-facing window
>for a few weeks and see what happens.
>
>kt
>
>
>On Jan 19, 2006, at 8:35 PM, Gordon J. Holtslander wrote:
>
>>
>>The liquitex is labelled:
>>
>>Liquitex Acrylic Gesso Transparent
>>has the number 7604 on the bottle
>>
>>label states
>>
>>"Flexible clear acrylic gesso for acrylic oil pastel and more"
>>
>>The white glue is
>>
>>Weldbond Universal Adhesive
>>
>>My foam roller was bought from the local Coop hardware store (my
>>favourite
>>photo supply store :) )
>>
>>Its a finishing roller a foam roller about 7 inches long 1 inch diameter
>>with a very fine nap.
>>
>>I charge it by pouring the gelatin mix in a narrow tray just larger than
>>the roller.
>>
>>I clean these just by rolling rinsing and squeezing out moisture.
>>
>>I often get fine bubbles from the roller - I will often wipe with a
>>finish
>>paint "pad" that has the same fine nap as the roller.
>>
>>I'm not claiming to get spectacular results. Just haven't been happy
>>with
>>the way I sized in the past - often got crappy sizing. Trying to see if
>>there are easier quicker better ways to size.
>>
>>Will try casein (and maybe casien -weldbond) for sizing too.
>>
>>Gord
>>
>>
>>On Thu, 19 Jan 2006, Judy Seigel wrote:
>>
>>
>>>
>>>On Thu, 19 Jan 2006, Gordon J. Holtslander wrote:
>>>
>>>
>>>>Liquitex make a clear acrylic gesso - I assume (bad practive) that is
>>>>has
>>>>no titanium whitener.
>>>>
>>>
>>>Definitions change over time -- I remember when a "dork" was a jerk,
>>>which is to say a nudnik, and now it seems it's an expert, geek or
>>>techie.
>>>So I say with some reservations that by definition *traditionally* a
>>>gesso
>>>had to have a whiting substance in it. To quote Mayer: It's made by
>>>mixing
>>>"an inert white pigment such as chalk, whiting or slaked plaster of
>>>Paris
>>>with an aqueous binder such as a solution of glue, gelatin or casein."
>>>
>>>I don't think by the way that gesso has titanium -- Mayer has a section
>>>on
>>>"Defects of Gesso panels" which I haven't read for 105 years, but my
>>>recollection is that they would be some kind of cracking, which
>>>presumably
>>>(better word than "assume," n'est-ce pas?) would be obviated by the
>>>gelatin.
>>>
>>>When I learned to make gesso, 103 years ago, we slaked plaster of
>>>Paris...
>>>and somewhere along the line I was told that *rotten* plaster made the
>>>best gesso, that is, you slake then keep a year or so til it rots. I
>>>made
>>>some up and worked off it for a long time -- I haven't used the gelatin
>>>gesso mix for a while (Bernie Boudreau's version is cited in P-F #6),
>>>because for my printing, plain Knox hardened in glyoxal or formaldehyde
>>>proved easiest & best. But I still have a couple of inches of the rotten
>>>plaster in a gallon container.
>>>
>>>That's the beauty of rotten plaster -- it keeps !
>>>
>>>PS. Gord: Does Liquitex call that clear stuff "gesso", or ...? Is
>>>"white
>>>blue" a misprint for "white glue"... or... ? (Elmers, maybe?) How do
>>>you
>>>clean the foam roller? Any special kind of foam?
>>>
>>>TIA,
>>>
>>>Judy
>>>
>>>
>>>
>>>>
>>>>I have been playing around with sizing techniques.
>>>>
>>>>Did a mix of gelatin (250 ml) and a little (20 ml) white blue, hardened
>>>>with chrome alum, rolled on with a foam roller. Seemed to give a much
>>>>smoother/cleaner surface than plain gelatin. But then the gelation
>>>>coat
>>>>may simply have been poorly coated.
>>>>
>>>>Gord
>>>>
>>>>On Thu, 19 Jan 2006, Ryuji Suzuki wrote:
>>>>
>>>>
>>>>
>>>>>I've tried gesso mix but one objection I had was that the acrylic
>>>>>gesso is gritty because of matting agents in the mix. Another
>>>>>objection I found is that the gesso contained titanium white and other
>>>>>things I would not want to have in my prints unless archivality is
>>>>>proven in the particular combination. Titanium white is very
>>>>>photoactive and generates a lot of radical chain reaction in the
>>>>>material when exposed to UV, and this was the main cause of problems
>>>>>in early days of RC papers. Photographic industry learned enough and
>>>>>today's products have good amount of means to prevent the problem, but
>>>>>I am not sure of gesso in sizing layer.
>>>>>
>>>>>
>>>>
>>>>---------------------------------------------------------
>>>>Gordon J. Holtslander Dept. of Biology
>>>>holtsg@duke.usask.ca 112 Science Place
>>>>http://duke.usask.ca/~holtsg University of Saskatchewan
>>>>Tel (306) 966-4433 Saskatoon, Saskatchewan
>>>>Fax (306) 966-4461 Canada S7N 5E2
>>>>---------------------------------------------------------
>>>>
>>>>
>>>>
>>>
>>>
>>
>>---------------------------------------------------------
>>Gordon J. Holtslander Dept. of Biology
>>holtsg@duke.usask.ca 112 Science Place
>>http://duke.usask.ca/~holtsg University of Saskatchewan
>>Tel (306) 966-4433 Saskatoon, Saskatchewan
>>Fax (306) 966-4461 Canada S7N 5E2
>>---------------------------------------------------------
>>
>
Received on Sat Jan 21 10:33:13 2006

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