Thread: White Resin

I use pigments from modelit or barnes in Diggers clear casting resin, fibre-glass resin or epoxy resins.

MIK I use powder paint for white.
Neil I was told not to use fibre-glass resin as it no good for pens so I take it it works for you then.
David

Fibre-glass resin is no good for translucent or pearlex type pigments as it is not a clear resin and can yelow with age. It is Ok for the solid type pigments, but perhaps you are right, not for white due to yellowing problem. I must admit I have only used it with black pigment.

It's good to know that you can use fibre-glass resin as this is cheaper then resin.
David

I also use the pre-dispersed pigments for poly resin from Barnes, about 5-10 gr pre-dispersed pigment per 100 gr of resin. These come in 100gr jars, which tend to be only half full, I mix them with poly resin as soon I get them, makes them easier to handle as some colours can be almost too thick to get out of the jar. So, once they are diluted with the poly resin, I use 10-20 gr per 100 gr.

My main casting resin is Quality Casting Resin from Barnes, $49.50 per 4 kg tin. I sometimes use the Water Clear resin, which is $60 a tin. Mainly where I need the clear properties, eg embedding or double casting over "glamourz" type blanks.

I never use fibreglass lay-up resin as it has not been designed for thick curing, only relatively thin films used in lay-up. This can create problems with the thicker sections, as it isn't that much cheaper than the Quality Casting resin from Barnes I don't take the risk.

As Big Shed said, layup resin isn't formulated for thick casting. It will crack. It can be used, but there isn't that much savings and it only comes in green, purple, and amber. Makes it hard to color.

As for pure white...

I use a top secret ingredient...

98.2% CaCO3
1.20% MgCO3
0.25% SiO2 0.12% Al2O3
0.06% Fe2O3
0.0035% MnO
0.2% Moisture

Hope that helps

I prefer 100% TiO2 myself.

Whiting is an extender rather than a prime pigment.

Titanium Dioxide in pure form is a bit pricey and inhibits the cure process. That would be why you think it's an extender. It is used as a primary pigment in paints for white also in toothpaste and even milk to get the white color.
Most, not all, pigments contain TiO2. That is what helps give opacity and it's irridescence or reflectabilty. The TiO2 is coated with metals and other chemicals to give it the many colors available.

thanks for the info guys

i ordered a can of quality casting resin by mistake last time, which has turned out OK regardless

does all "quality casting resin" have a black tinge to it, almost like small particles floating in the resin???

i will be getting the clear resin next time for the brighter colors that i want to cast

i have also found with the "quality casting resin" that it seems to cure a lot quicker and is a lot more brittle than the clear resin. is this also a standard??

MIK

Originally Posted by Resination

Titanium Dioxide in pure form is a bit pricey and inhibits the cure process. That would be why you think it's an extender. It is used as a primary pigment in paints for white also in toothpaste and even milk to get the white color.
Most, not all, pigments contain TiO2. That is what helps give opacity and it's irridescence or reflectabilty. The TiO2 is coated with metals and other chemicals to give it the many colors available.

Sorry sir, you are talking to a paint chemist with in excess of 40 years experience. To call the above "inaccurate" is being kind.

The chemical combination you were listing before is calcium carbonate, or whiting.

I would suggest you read a reasonably accurate source, such as Wikipedia, on TiO2 and also on coloured pigments and you will find that what you said above is not fact.

TiO2, or Titanium Dioxide is the most widely used white pigment in the world, not only in paint, it does neither speed up or retard the curing of polyester resin.

I'm not familiar with "quality casting resin", but it sounds similar to Castin' Craft resin. Much more brittle. Who is the manufacturer?

I didn't say it was only used for paint. For that matter, you can read wiki and you tell me what is not fact. I have researched pigments extensively and even have worked with some manufacturers. All irridescence in pigments comes from coated TiO2.
Calcium carbonate is widely used as a white pigment and with resins, has NO adverse effect.
As far as resins, you should do some research on that as well. TiO2 WILL inhibit cure.

I never said you were inaccurate, but as a chemist, show the supporting information from more than one source that shows my info. as being wrong.

Originally Posted by Big Shed

Sorry sir, you are talking to a paint chemist with in excess of 40 years experience. To call the above "inaccurate" is being kind.

The chemical combination you were listing before is calcium carbonate, or whiting.

I would suggest you read a reasoably accurate source, such as Wikipedia, on TiO2 and also on coloured pigments and you will find that what you said above is not fact.

TiO2, or Titanium Dioxide is the most widely used white pigment in the owrld, not only in paint, and is chemically inert. As such it does neither speed up or retard the cureing of polyester resin.

there is no manufacturer listed but i got it from here http://www.amcsupplies.com.au/catalo...ex&cPath=8_154