CR-39 material

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CR-39 material 

Allyl diglycol carbonate or Columbia Resin. CR-39 is a light transparent plastic material (refractive index 1.498, V = 59) used in the manufacture of spectacle lenses and much harder than polymethyl methacrylate. It is not quite as hard as glass. Syn. hard resin. See constringence; plastic lens.
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On average, Lawter's hard resin prices are being increased $0.
The core uses a hard resin to form the tough coating that ICT equipment needs, resulting in coating performance suitable for use in ICT equipment chassis.
A much better option for DIYers is hard resin (hard polyurethane) ceiling roses, which are a lot lighter and come in a wide range of sizes and styles.
Pointe shoes contain a hard resin block in the toe box, which can cramp and crush the toes, causing blisters, corns and split toe nails.
A much better option for DIY-Y ers is hard resin (hard polyurethane) ceiling roses, which are much lighter and come in a wide range of styles and sizes.
A much better option for DIYers is hard resin (hard polyurethane) ceiling roses, which are much lighter and come in a wide range of styles and sizes.
The hard resin can damage cartilage by repeated motions, especially under high loads.
Urethane Acrylate Resin B is a hard resin that is 60% solids in n-butyl acetate and has a viscosity of 200 mPas at 25[degrees]C.
PPG Industries is the world's leading maker of optical resins and introduced the first hard resin lens material, CR-39 monomer, in 1946.
In the past, medium density fiberboard, or MDF--a dense, smooth particleboard made of compressed fine sawdust and hard resin glue--was typically used as a backing for hardwood veneers.
The viscosity of the products increases with reaction time up to the formation of hard resin.