From: tozuss-AT-aol.com
Date: Wed, 12 Jan 2005 15:36:25 EST
Subject: Re: [Puptcrit] Re: gloss problems
To: puptcrit-driftline.org-AT-lists.driftline.org


i asked a chemist about the paint problem mathieu presented. here  is the
chemist's  reply.....

Matte and gloss response in architectual coatings are basically  controlled
by binder to pigment ratio .  I'll spare you the  treatice.

However in the system under discussion it is desired to  have  mostly binder
- ( acrylic polymer) in order to retain the clear  transparent character of
the finish.

So in this case the mechanistic  approach must be to increase the surface
roughness - since this increases  light scattering and reduces gloss.

Surface roughness can be increased  through use of a transparent pigment as
a minor component mixed with  binder..

3M sells a product that is glass microspheres  of various  particle sizes.
These are transparent when blended with a binder (such as  acrylic resin)

Yet dramatically affect the light scattering of the  system.

I would suggest that the artist first apply the clear coat then  add on top
a second thin finish coat of acrylic + glass microspheres  product.

Very fine high grade sand may also do the same trick:  I  have blended fine
sand with epoxide resin in order to produce a clear  non-skid deck finish
for a boat.

Experiment first on a test surface to  see the  effect.

CB






01/11/2005 07:35         cc:           
PM           Subject: can you help this  puppeteer                     







----- Message from "Mathieu"  <creaturiste-AT-magma.ca> on Tue, 11 Jan 2005
19:46:59 -0500  -----

To:  <puptcrit-driftline.org-AT-lists.driftline.org>

Subject: [Puptcrit] "Killing" the gloss    



HI all. Ahev you ever struggled to solve this era's  most frustrating
painting tragedy?
The unwanted plastic-y  GLOSS!


WELDBOND'S LAST FLAW
One thing I still need to solve:  Weldbond may be the best glue/paint medium

I've tried, it does have this  "acrylic paint gloss" which I want to get rid

of.

ACRYLIC PAINT  SHARES THIS GLOSSY FLAW
Acrylic paint, when the finish is not mentionned on  the label, is usually
glossy, and the glossyness even varies from color to  color, in the same
variety and quality of paint. What's a matte-loving artist  to do?
I prefer to avoid buying matte acrylic paints, as they are already  filled
with fillers and additives. Makes the paint mixing more complicated,  you
get
"dusty" colors, and an automatic semi-opacity, which can be a pain  if, like

me, you love transparent glazes.

My goal is to get a nice  matte finish, to get as close as I can to
naturally
matte materials. I  prefer to use other varnishes and mediums to really
control gloss when I  really need it (which is rarely the case, as I hate
the
gloss since I work  in theatre. It is bad for lighting!.)

Right now, my current project ( a  mask) is painted in a very satisfying
way,
but has that annoying and  distracting "plasticy" visual feel to it.  I
tried
adding matte  medium on top, but it only killed the gloss a bit, and if I
had
put more  of it, I would have killed the depth of colors even more than I
already did (  i had to repaint a lot of it back).

Powdery additives in the matte  mediums usually make the dark colors "dusty"

when I try to use it in the  mix, or as a mattifying coat...
I'm doing some tests tonight with rubbing  alcohol, and will let the group
know.
I was told that a mix of rubbing  alchool and pure PVA glue (not the white
glue from craft or hardware stores)  like Vinavil(brand), makes a nice
mattifying agent on top of a good paint  job. I've seen the result, and it
works, but haven't tried it myself with my  own paints or with my
Weldbond-based paint mix..

Also, this technique  has to be tested overtime to make sure the specific
glue formula  (in  reaction with alcohol) won't go dusty and white from sun
or other light  exposure. I've had this nightmare happen with regular white
glue applied (by  itself) as a varnish on top of a puppet before.


What I think makes  the matte effects is probably  because of additives(that

change  light refraction and absorbtion), and others are because of the
actual  surface of the paint. Maybe the rubbing alcohol trick is  explained
by
microscopic abrasion of the surface of the  paint?
HELP!

My questions to the group are:
-Does anybody have a  magical tip that can save us all from the Acrylic's
glossyness?
-Do you  have a background in chemistry to help us understand what makes a
surface  glossy or matte, so we can find a logical solution?
-Or what is your favorite  mattifying agent/technique?

Thanks in advance to all who will scratch  their heads inside-out for
solving
this contemporary-age-old  tragedy...





Mathieu René Créaturiste
Marionnettes,  Masques, Etcetera...
Puppets, Masks,  Etcetera...
creaturiste-AT-magma.ca
www.creaturiste.com
(514)  274-8027
Mathieu René Créaturiste
Marionnettes, Masques,  Etcetera...
Puppets, Masks,  Etcetera...
creaturiste-AT-magma.ca
www.creaturiste.com
(514)  274-8027

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