About care and restoration of polycarbonate (lexan
The three main types of clear plastic used on sailboats are "isinglass" (clear vinyl), polycarbonate (lexan and some other trademarks) and acrylic (plexiglass, or "perspex" to the Brits.). Clear Acrylic is the most light transparent of all materials (even more transparent than glass) and can be heat molded, bend and welded (with acetic acid. Plates of plexiglass are not affected by most cleaners and solvents, but as plexiglass ages (or if heat bent it is not annealed) there are stress risers that cause "starring" or "crazing". If on the surface only it these can be polished out using decreasing grit size. You can use Clear Horizons safely on new or old ("starred") acrylic, but not our undiluted cleaners. You can use IG Pink with lots of water dilution or just mild detergent in lots of water for cleaning. If slightly scratched use Meguirs. Now that this is out of the way we go to Lexan and (behaves somewhat the same) clear viny. If you have ever seen a new piece of lexan or clear vinyl and looke at the edge it has a "blueish" tinge. This tint, plus optical brightener is used to "correct" the slightly yellowish color. This becomes very obvious as the plastic ages and gets the "yellowish" tinge. This is most noticeable on the surface due to surface oxidation and (in the case of clear vinyl) some plasticizer exudation similar to that seen on fender tops. Clear Horizons is useful for keeping the surface of NEW clear lexan or clear vinyl slick, water repellent and the small scratches filled so increasing clarity (similarly with clear glass). ANy of our cleaners can be used to remove marker pen markings, gobs of sealant , paint etc without damage. However, as the surface ages a yellowish surface deposit is formed (mainly oxidation). If only slightly yellowed you can polish off with metal polish or Meguires plastic polish. However, if there is Bad surface yellowing, use either our Sea Glow or Neutral Clear Cleanser/Conditioners. These chemically dissolve off the oxidation (as seen coming off on the paper towel swab), Keep going til all stickiness is gone, then. Neutralize with water, remove any surface milkiness with metal polish (smoothes too) and then seal with Clear Horizons. I have restores almost new clarity to lexan windows on a catamaran in Santa Cruz Harbor (about 4-5 years ago after a West Marine Demo). I have done my 8 year old lexan storm windows twice (last time in Feb of 2001) and the effects last a long time because of the anti-oxidants and UV protectant in the conditioner- this penetrates a bit (as can be seen by a UV light when using the Sea Glow). Clear vinyl is completely restorable if just a bit milky, but when it is really dark brown on removal of the surface the oxidation leaves a pitted surface (as for removing rust from metal). However you can still get useful clarity for shapes, even if not in original detail. This helped me put off getting a new rear window for a convertible car for over a year and a half. Thanks ALW Yeah! I no its too much but once I get going......!
