Ultraviolet protective coatings

Figure 7.1 HSG has pioneered the commercialization of ultraviolet-curable hybrid glass protective coatings. 

Diamond like films are amorphous, smooth and lightweight. The ability to produce very thin (2-6 nm) and smooth films together with low atomic number makes these films an ideal material for use as protective coatings on x-ray mirrors. Also, these films are scratch/chemical resistant and block ultraviolet radiation. These properties taken together can revolutionize the spectacle and goggle industry. These properties... 

URL USEPA UV WCOT WWW uniform resource locator United States Environmental Protection Agency ultraviolet wall-coated open tubular (column) World Wide Web... 

Virtually all polymers deteriorate under exposure to outdoor weathering and solar radiation, but at greatly varying rates. Polymers In solar equipment must maintain optical, mechanical, and chemical Integrity despite prolonged exposure to solar ultraviolet radiation. For most outdoor applications of polymers, solar radiation exposure Is Incidental, but for many solar applications, exposure to solar radiation Is deliberately maximized In the equipment design. Transparency Is essential for many of the potentially most cost-effective applications, and conventional approaches to ultraviolet protection such as opaque coatings and fillers are unacceptable. 

Products and Uses Found in sunscreening products and protective coatings as a UV (ultraviolet) light screening agent. 

Polymers can also be used to manufacture lenses and screens for projection television systems. These are most conveniently made from PMMA, or combinations of glass and PMMA, to counteract the high thermal expansion of the polymer. The use of ultraviolet curable coatings for lens replication and protective layers is widespread, and these systems are based on diacrylate or dimethacrylate monomers mixed with photoinitiators such as... 

Still, poljrmers containing Si, Ge, Sn, or Pb chains cannot be expected to show the stability of their carbon analogs. A large plastics industry based on such derivatives cannot be imagined at present, but practical applications in which chemical inertness is not an important factor may well be developed for the compounds. Already, the recently observed ultraviolet properties of polysilane chains suggest applications as protective coatings. Doubtless,... 

The focusing of radiation within the instrument was formerly done by means of lenses, but these suffer from chromatic aberration and particularly in respect of the relationship between the visible and ultraviolet parts of the spectrum. Focusing is now usually carried out by means of suitably curved mirrors having a reflecting surface coated with aluminium which is protected by a silica film. 

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