[Alt-photo] Increase in Dmax
pitcherd1 at msn.com
Mon Mar 2 15:18:18 UTC 2015
Here is a link to a full product description of the Ludox line from Grace, the manufacture. The are using a sodium anion to keep the silica in suspension. https://grace.com/general-industrial/en-us/Documents/ludox_br_E_2012_f120504_web.pdf
I have worked with the more acidic version in attempts at creating alternative subbing solutions for glass or non porous surfaces.
Sent from my iPad
> On Mar 2, 2015, at 5:00 AM, Loris Medici <mail at loris.medici.name> wrote:
> Hi Massimo, interesting information. Thanks for sharing.
> I went to Sigma Aldrich site and it says the product has a pH value 9.8,
> which is pretty alkaline. Silica should be pH neutral, therefore, I think
> there's something more in the product - apart SiO2, that helps keeping
> silica in suspension, which is alkaline...
> Which process were you using?
> 2015-03-02 14:51 GMT+02:00 Info (GEO) <info at geostudio.com>:
>> I tested paper precoat "Revere Platinum" with Fumed silica suspension
>> Sigma Aldrich (LUDOX) applied with coating road.
>> The Dmax increases from 1.45 to 1.65 (measured by densitometer TOBIAS
>> IQ150), without streaks, grainless and with good uniformity, but the finish
>> looks like semi-matt, not good for me.
>> Now I try with a preparation of Evonik (AERODISP) that should not alter
>> the opacity of the paper and I'll let you know.
>> Has anyone had any experiences with these products or with similar
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