Lenses, contact

Contact lenses can be colored or tinted to provide a variety of effects to change the appearance of the eye (90). This can be done to correct a problem with the appearance of the eye or for cosmetic purposes. Such contact lenses can be used to enhance a particular aspect of one s appearance. [Pg.278]

A colored printing ink for contact lenses has been detailed (91,92). A method for making a hydrophilic contact lens is comprised of the steps of providing a polymeric contact lens and coating a portion of a surface of the lens with a coat. This coat contains a colorant, and a crosslmked binder polymer. The binder polymer entraps the colorant and adheres to the lens. A binder polymer for a colored base ink is summarized in Table 7.12. [Pg.278]

Isocyanate compounds should be avoided for such applications. [Pg.278]

A dispersant or a surfactant is preferably employed if inkjet printing is used for deposition. The optimal viscosity of the color coat is determined largely by the method by which the coat is applied to the lens. If the color coat is to be applied by inkjet printing, the viscosity of the ink should be less than 15 cP (93). A preferred composition is summarized in Table 7.13. [Pg.280]

The preferred lens-forming material is a sUicone hydrogel. The components of a binder polymer for a clear base ink composition are shown in Table 7.14. [Pg.280]

Contact lenses in general use, either hard or soft, are apt to be contaminated with bacteria and fungi as microorganisms easily grow between the contact lens and the cornea because of moisture, temperature and nutrients (10). [Pg.65]

Water-containing soft contact lenses, while comfortable to apply, are susceptible to bacteria and fungi both on the surfaces and the inside because of their own hydrophilic properties as well as their high water content, tending to cause serious infectious diseases. Moreover, they demand care in handling and involve tedious treatment for sterilization. [Pg.65]

Where antimicrobial properties are imparted to a contact lens per se, special care for safety is required for a contact lens comes into direct contact with the cornea and the conjimctiva, and any substance eluted from the lens is carried by tears to the digestive tract. Accordingly, an antimicrobial substance to be incorporated into contact lenses and related articles is essentially required to have high activity and heat stability and to be firmly fixed so as not to be dissolved out. With these considerations in mind, phosphonium salt type polymers are deemed to be suitable. [Pg.65]

An antimicrobial polymer can be obtained by the polymerization of an one phosphonium salt type vinyl monomer, e.g., 2-(methacrylic [Pg.65]

For example, contact lenses are prepared by the copolymerization of 2,2,3,3,4,4,4-heptafluorobutyl methacrylate, tri-n-octyl-3-vin-ylbenzyl phosphonium chloride, methyl-di(trimetiiylsiloxy)silyl-propyl methacrylate, and ethylene glycol dimethacrylate. Isopropyl percarbonate is used as radical initiator. The resulting resin rod was cut and polished to obtain the contact lenses (10). [Pg.66]

See also in sourсe #XX -- [ Pg.184 ]

See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.102 , Pg.124 ]

See also in sourсe #XX -- [ Pg.175 ]

See also in sourсe #XX -- [ Pg.7 ]

See also in sourсe #XX -- [ Pg.508 ]

See also in sourсe #XX -- [ Pg.20 , Pg.21 , Pg.22 , Pg.23 , Pg.24 ]

See also in sourсe #XX -- [ Pg.123 , Pg.130 ]

See also in sourсe #XX -- [ Pg.7 ]

See also in sourсe #XX -- [ Pg.13 ]

See also in sourсe #XX -- [ Pg.112 ]

See also in sourсe #XX -- [ Pg.171 , Pg.172 , Pg.173 , Pg.174 , Pg.175 , Pg.176 , Pg.177 , Pg.178 ]

See also in sourсe #XX -- [ Pg.204 , Pg.232 ]

See also in sourсe #XX -- [ Pg.29 ]

See also in sourсe #XX -- [ Pg.349 ]

See also in sourсe #XX -- [ Pg.7 ]

See also in sourсe #XX -- [ Pg.215 ]

See also in sourсe #XX -- [ Pg.7 ]

See also in sourсe #XX -- [ Pg.308 , Pg.326 ]

See also in sourсe #XX -- [ Pg.20 ]

See also in sourсe #XX -- [ Pg.310 ]

See also in sourсe #XX -- [ Pg.592 ]

See also in sourсe #XX -- [ Pg.82 , Pg.94 , Pg.132 , Pg.230 ]

See also in sourсe #XX -- [ Pg.88 , Pg.167 , Pg.175 , Pg.188 ]

See also in sourсe #XX -- [ Pg.7 , Pg.8 , Pg.9 , Pg.10 , Pg.11 , Pg.12 , Pg.13 ]

See also in sourсe #XX -- [ Pg.278 ]

See also in sourсe #XX -- [ Pg.188 ]

See also in sourсe #XX -- [ Pg.1373 , Pg.1375 ]

See also in sourсe #XX -- [ Pg.328 ]

See also in sourсe #XX -- [ Pg.57 ]

See also in sourсe #XX -- [ Pg.10 , Pg.141 , Pg.393 , Pg.402 , Pg.403 , Pg.404 , Pg.405 , Pg.406 , Pg.407 , Pg.408 , Pg.409 , Pg.672 , Pg.674 ]

See also in sourсe #XX -- [ Pg.158 ]

See also in sourсe #XX -- [ Pg.65 ]

See also in sourсe #XX -- [ Pg.33 , Pg.37 ]

See also in sourсe #XX -- [ Pg.85 ]

See also in sourсe #XX -- [ Pg.293 , Pg.294 , Pg.295 , Pg.296 , Pg.297 , Pg.298 , Pg.299 , Pg.300 , Pg.301 , Pg.302 , Pg.303 , Pg.304 ]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...