The "standard plastic" lenses are often called "Hard Resin", "CR-39 plastic", or just quot;plastic" lenses. CR-39® is actually a PPG Industries registered trade name for a DADC (diallyl diglycol carbonate) polymer that was introduced in 1941. The "CR" stands for Columbia Resin and CR-39 was the 39th batch or formula made by Columbia Laboratories in Ohio.

Glass: Glass offers the best optical clarity, meaning that there is virtually no distortion in glass lenses. This is why it is the material of choice in manufacturers such as Ray-Ban, Revo, Vuarnet, and Serengeti. However, glass is the least impact resistant of all of the material, and may shatter upon impact. Shattering means that the lens will split into small pieces which can easily enter the eye and cause permanent eye injuries or even blindness. See similar questions...

Solexx greenhouses are made with polyethylene. Polyethylene is much more flexible and is easy to cut to any size. Polycarbonate panels tend to be thicker, but have about the same insulation factor as polyethylene. Both materials diffuse light, but polycarbonate diffuses less (because it is more transparent), making the greenhouses much hotter in the summer. Polyethylene is very easy to clean and will not scratch like polycarbonate. See similar questions...

CR-39 refers to the type of plastic that is used to make prescription lenses. This is optical plastic and provides very little distortion .It is more lightweight and thinner than glass making it comfortable to wear. It is more impact resistant than glass, but may still break and shatter upon impact. Therefore, it is not recommended for active sports and motorcycling. It is more scratch resistant than polycarbonate, but will scratch if not properly taken care of. See similar questions...

We do not recommend this nor do we install film on it. However below is Llumar ? documentation regarding this question we are asked often which may be beneficial to you in answering the question you have been searching for: The answer is somewhat complex. Generally speaking, the simple and flat answer (as of January 2000) is "NO," though research is always on-going and new specialty products more compatible with plastic sheeting are always a future possibility. See similar questions...

Acrylic is sold under the trade name Plexiglass? and polycarbonate is sold under the trade name Tuffak? or Makrolon?. The plastics manufacturer we work says that acrylic is more weatherable than polycarbonate, is slightly more scratch resistant, and is more economical than polycarbonate. Polycarbonate has greater impact resistance than acrylic, and is more expensive. See similar questions...

Polycarbonate is the other material commonly used in domed skylights. Polycarbonate is used in applications where impact resistance is a requirement. It is the material used in our Miami-Dade Approved Hurricane Impact Skylights. It is even popular in areas that may be prone to Hail Damage. Polycarbonate can be formed just as easily as acrylic. See similar questions...

Polycarbonate lens material is so tough that you can hit it with a hammer and it won't shatter. Ordinary polarizing lenses are made out of plastic (CR-39), and are not shatter resistant. In addition, polycarbonate lenses absorb harmful UV radiations. See similar questions...

Our current top of the line plastic is called Champion plastic. Since the original introduction of the Champion (Candy) plastic, it has gone through three name changes. All three are basically the same family of semi-clear or pearlescent plastic. When the Champion plastic was first introduced, it was called Champion Edition (CE). Then it was briefly called Pro-Line. (Pro now refers to our current line of grippy, opaque discs made with a unique blend of plastics. See similar questions...

Pro plastic is our current line of discs that use an opaque blend of plastics. Special Edition or SE plastic was available in limited runs until 2003, and is most like our current Pro Line of discs. Go to About our Plastics for a complete explanation about our current plastics. See similar questions...

Plastic will not rust, it is light weight, easier to handle and release, is more cost effective and has exactly the same holding force as the metal does. Grip Fast™ collars are warranteed for one full year after date of purchase - assuming normal use. See similar questions...

Less expensive clarinets (student models) are often made with plastic (commonly ebonite). These will not crack with changes in humidity and temperature as the wooden models do, but they lack the character of sound of the wooden models. See similar questions...

Fiberglass uses a different resin and has thin glass strands in it which, when hard gives it great strength and durability. It's a good product to use where increases strength is required and for filling holes. It's also waterproof. See similar questions...

The title “Facial Plastic Surgeon” generally describes a surgeon who specializes in facial plastic and reconstructive surgery. The title “Plastic Surgeon” generally describes a surgeon who performs the gamut of plastic surgery procedures, from head to toe. A patient seeking breast augmentation would seek out a “Plastic Surgeon” rather than a “Facial Plastic Surgeon. See similar questions...

Facial plastic surgeons perform cosmetic and reconstructive surgery on the face, head, and neck regions only. Training includes one or two years of post-graduate training in general surgery residency, at least four additional years of specialty training in head and neck surgery, and subspecialty fellowship training in facial plastic surgery. A general plastic surgeon performs both face and body procedures. See similar questions...

For more specific questions regarding a particular surgery, visit our contact us page and we will gladly send you a customized packet. See similar questions...

Plastic surgery is one of the nine main specialties recognised by The Royal College of Surgeons (eg orthopaedic surgery, urology). See a description of each specialty. Consultant plastic surgeons are listed as being fully trained in this specialty on the General Medical Council's (GMC) Specialist Register. You can check this on the GMC website (www.gmc-uk.org; Tel: 020 7580 7642) or at public libraries. See similar questions...

Cosmetic surgery is performed for aesthetic reasons, whereas plastic or reconstructive surgery is usually performed for medical reasons. See similar questions...