Special material question - Refraction glossiness

[Deflaminis]

Hello, thanks for looking in.

I need to recreate a rather unique material. It's got a property to it that I'm not sure how to approach and I'd hoped to ask here for a bit of guidance. To put it shortly, the internal refractive glossiness is different than the outer glossiness. Think a block of plastic that is super glossy but has the outer edges roughed up to create a non glossy effect on the outside, yet somehow not very reflective at glancing angles.

Simply making the whole shape non-glossy internally doesn't trasmit the light properly when at an angle, so my initial test was bupkis. How would I go about this?

I was thinking maybe using a distance tex with a copy of the object set to non-renderable just outside the surface to assign a different glossiness there, but I'm not sure this is the best way. SSS maybe? (2 sided material? Will that work on non-planar objects?) It's a diffusion coat of sorts on acryllic, maybe related to surface roughness. (Sort of a matte finish on the outside.)

Is there another way to set the outer faces to have a specific refractive glossiness yet keep the inside with a smooth 1.0-.98 glossiness? Am I talking crazy?

The spec sheet: http://www.3-form.com/downloads/3for...oma_rev035.pdf

The spec sheet says 92% transmission of light through the surface. Does this mean 4% on the way in on one side, and 4% on the other side? Should my refractive color be 245 or 235? (Meaning, do I need to count both sides with a 2 sided material, giving each side 96% transmission?)

Thank you!
AJ

EDIT: A 2 sided material seems to be working the best. I think it's exactly what I needed, though I have some tweaking to do. Any thoughts appreciated. Added some images here and below for reference.

[Deflaminis]

Here's some screens of what I'm trying to do. Using a straight material with low gloss refractions makes the outer edges too dark due to the IOR here (which is fixed) but on the real material this never seems to happen. I've gotten this far with 2 sided, and adjusting the translucency color does seem to help but I need to do some renders there to see how much.

As you can see, there are 2 main problems I'm having. 1) The dark isn't staying dark, you can see it in the dark areas of the checker. I'm not sure how to deal with that. (levels I guess in post or a brighter black checker maybe). and 2) The edges aren't dark enough and they tend to be too glossy. My angle might be the problem there since we're not refracting the edges from here. Curious if anyone else has done something like this for a pointer or two.

Also curious how to calculate transmission with a solid object that has 2 sided materials on it. Guessing seems to work fine, but I was just curious.

EDIT: I think I solved it with a falloff in the translucency slot. Thanks!