Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Polymers from only ethylenic monomers or processes of...
Patent
1996-02-23
1998-08-11
Smith, Jeffrey T.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Polymers from only ethylenic monomers or processes of...
526241, 526266, 526286, C08F 3004
Patent
active
057928223
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to a transparent plastic material which selectively blocks only light of a specific wavelength and having the function to blocking ultraviolet which does harm to human eyes and selectively blocking or reducing light of a specific wavelength which is dazzling to the human eye, easier to be manufactured and lighter than conventional materials and stable over time, and an optical article comprising the material.
BACKGROUND OF THE INVENTION
When adapted to light, the human eye perceives light in the vicinity of 555 nm (520 to 590 nm) in wavelength to be the brightest, and when adapted to the dark, the human eye perceives light in the vicinity of 507 nm (472 to 542 nm) in wavelength to be the brightest. This is the reason why a person feels dazzled when he rapidly enters a dark place from a dark place or, to the contrary, nothing is visible for a time when he enters a light place from a dark place. Further, the above phenomenon is also the reason why he feels very dazzled under strong sunlight such as outdoors in the daytime during fine weather, at the seashore or mountains in summer. As a result, to prevent such glare, sunglasses are generally used. However, since sunglasses use only colored lenses, the sight becomes dark. Further, those lenses which do not appropriately absorb ultraviolet light (do not block ultraviolet light) expand the pupil due to the darkness of the sight allowing the amount of ultraviolet light entering the eye to increase. This ultraviolet light is harmful to the human eye, and light of 280 to 315 nm in wavelength (UV-B) is said to be absorbed by the cornea to cause difficulties for the cornea such as inflammation of the cornea. Further, ultraviolet light of 300 to 400 nm in wavelength (UV-A) is said to reach the lens of the eye and is absorbed, and extended exposure to ultraviolet light is considered to be a cause of senile cataract. Therefore, sunglasses which do not cut ultraviolet light cause heavy physiological burden to the eyes. Further, to prevent the occurrence of cataract, it is necessary to cut ultraviolet light which is harmful to the lens of the eye.
Neodymium compounds, which are rare earth compounds, have a sharp absorption in the vicinity of 570 to 590 nm and can selectively absorb only light of wavelengths which are dazzling to human eyes. Therefore, utilizing these properties, neodymium compounds are incorporated into glass to endow eyeglass lenses and automobile mirrors with glare-proof properties. At the same time, introduction of neodymium compounds into transparent plastics to obtain highly transparent optical plastics with glare-proof properties has been investigated. Some examples are given below:
This patent discloses a method for producing a light blocker in which an organic thin film from a water-soluble polyether containing a water-soluble rare earth metal salt such as neodymium or cerium is attached to the inner surface of a mold comprising glass or a metal, and a inethacrylic ester or an acrylic ester and a prepolymer of an a,b-unsaturated carboxylic acid are injected into a mold, followed by heat polymerization.
This patent discloses a resin composition comprising an inorganic neodymium compound such as neodymium phosphate, neodymium carbonate, neodymium sulfate, neodymium oxide, or neodymium nitrate mixed with a synthetic resin.
This patent discloses a resin composition comprising an organic neodymium compound such as neodymium ethylenediamine-tetraacetate, neodymium acetate, or neodymium stearate mixed into a synthetic resin such as methylmethacrylate resin or styrene resin.
This patent proposes a selective light absorbing resin composition for the visible light region comprising particles of a neodymium compound such as neodymium oxide, neodymium hydroxide, neodymium carbonate, neodymium phosphate, neodymium sulfate, neodymium chloride, or neodymium acetate having an average particle diameter of 0.2 to 20 .mu.m dispersed in a transparent plastic base material.
However, conventional neodymium compounds su
REFERENCES:
patent: 5384379 (1995-01-01), Bader et al.
Kinoshita Jun
Miyabayashi Toshiyuki
Seiko Epson Corporation
Smith Jeffrey T.
LandOfFree
Transparent plastic material, optical article based on the mater does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transparent plastic material, optical article based on the mater, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transparent plastic material, optical article based on the mater will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-389668