Compositions: coating or plastic – Coating or plastic compositions – Metal-depositing composition or substrate-sensitizing...
Patent
1977-04-20
1978-06-06
Douglas, Winston A.
Compositions: coating or plastic
Coating or plastic compositions
Metal-depositing composition or substrate-sensitizing...
106 47Q, 106 52, C03C 310, C03C 304, C03C 330
Patent
active
040934691
ABSTRACT:
An optical glass article having a desired surface figure and demonstrating maximum theoretical light transmission can be prepared by forming a base anhydrous glass of defined compositional ranges, hydrating the glass, partially dehydrating the glass at a temperature above the softening point and, using an inert gas, at a pressure above the vapor pressure of water contained therein, and then molding a preformed blank of the glass against a die having a desired optical quality surface figure, the molding being under conditions sufficient to transfer the surface figure of the die to the glass. The base glass comprises, in mole percent, about 70 to 82% SiO.sub.2, 10 to 17% Na.sub.2 O and/or K.sub.2 O, and 5 to 15% of an oxide or oxides selected from ZnO and PbO. The water content of the partially dehydrated glass ranges from about 3 to 8 wt. percent and the molded glass has a substantially uniform refractive index throughout its bulk. Homogeneous distribution of the water throughout the glass bulk appears to be assured by limiting the total water content to a range at which the diffusion coefficient of the water species (H.sub.2 O, H.sup.+, and OH.sup.-) exhibits the greatest dependence on the total water concentration (i.e. the range at which the coefficient is a quasi-step function).
REFERENCES:
patent: 3498802 (1970-03-01), Bickford et al.
patent: 3498803 (1970-03-01), Stookey
Sanford Leon M.
Wu Che-Kuang
Bell Mark
Corning Glass Works
Douglas Winston A.
Giblin James A.
Janes Jr. Clinton S.
LandOfFree
Molded glass articles having bulk homogeneity and optical qualit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Molded glass articles having bulk homogeneity and optical qualit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Molded glass articles having bulk homogeneity and optical qualit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1491226