The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 2006
Filed:
Oct. 23, 1996
Kazunori Kagei, Sabae, JP;
Tadashi Kobayashi, Sabae, JP;
Kazunori Kagei, Sabae, JP;
Tadashi Kobayashi, Sabae, JP;
Asahi Lite Optical Co., Ltd., Fukui, JP;
Abstract
A base lens of a polyurethane resin comprising a polyisocyanate compound and a polythiol, a sulfur-containing polyol or the like is coated with a primer layer having a thickness sufficient for shock absorption, an organosiloxane-type, hard coat layer having a refractive index of 1.47 or more, and optionally a thin metal layer in that order. As having this constitution, the plastic lens has a mechanical strength resistant to striking energy of not smaller than 4 times the striking energy value of the FDA Standard, 0.204 joules, when the center thickness of the lens is from 0.7 mm to less than 1.2 mm. Since the latitude in the acceptable range for the conditions for the processing of the lens (relative to the thickness of each constitutive layer) is large, the producibility of the lens is high. An inhomogeneous layer may be formed between the adjacent layers, which reduces the reflectivity of the lens for transmitting light and prevents the formation of interference fringes in the lens. An ultraviolet absorbent, if added to the hard coat layer, can cut off ultraviolet rays, while preventing the base lens and the coat layers from being aged, and is helpful in protecting eyeballs.