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US4944962A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for dirtproofing treatment for plastic lens

Assignee: Itoh Optical Industrial Co Ltd
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Filing: 1988-10-24
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Granted: 1990-07-31
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Expires: 2008-10-24
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Abstract

Abstract A method is disclosed which concerns the treatment for imparting dirtproofness to a plastic lens provided in advance on the surface thereof with an antireflection film formed by vacuum evaporation of an inorganic substance. This method forms a dirtproofing film on the antireflection film by mixing a polyfluoroalkyl silane-containing coating liquid and trichlorotrifluoroethane and boiling the resultant mixture, dip coating the plastic lens in the boiled mixture, then treating the dip coated plastic lens with the vapor of fluoroethane, subsequently drying the wet plastic lens with hot air, and optionally immersing the dried plastic lens in water.

Inventors

  • 👤 Shoichiro Furuta
  • 👤 Hirohisa Kato
  • 👤 Hirohito Seto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 11:50
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G02B1/113; G02B1/115; G02B1/105; G02B1/14; B; B29; B29L; B29L2011/00; B29L2011/0016

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 104 words
A method for the impartation of dirtproofness to a plastic lens provided in advance of a film formed by vacuum evaporation, which method comprises the steps of: (a) mixing a polyfluoroalkyl silane-containing coating liquid and trichlorotrifluoroethane in a gravimetric ratio in the range of 1/2 to 1/10 and boiling the resultant mixture, (b) subjecting said plastic lens to a dip coating treatment in the boiled mixture, and (c) removing said plastic lens from said boiled mixture and dried with hot air under the conditions of 1 to 5 minutes×40° C. to 60° C. thereby forming a dirtproofing film on said film of vacuum evaporation.
Claim 2
Independent Claim 104 words
A method for the impartation of dirtproofness to a plastic lens provided in advance of a film formed by vacuum evaporation, which method comprises the steps of: (a) mixing a polyfluoroalkyl silane-containing coating liquid and trichlorotrifluoroethane in a gravimetric ratio in the range of 1/2 to 1/10 and boiling the resultant mixture, (b) subjecting said plastic lens to a dip coating treatment in the boiled mixture, and (c) removing said plastic lens from said boiled mixture and dried with hot air under the conditions of 1 to 5 minutes×40° C. to 60° C. thereby forming a dirtproofing film on said film of vacuum evaporation.
Claim 3
Dependent Claim 26 words
A method according to claim 1, which further comprises a step of immersing in water the plastic lens after said step of drying with hot air.
Claim 4
Dependent Claim 24 words
A method according to claim 1 or claim 2, wherein a hard coat is interposed between said substrate and said film of vacuum evaporation.

References Cited (Backward Citations)

US4096315A Cited
US4338375A Cited
US4374158A Cited
US4382983A Cited
JPS58211701A Cited
JPS5913202A Cited
JPS6118901A Cited
US4769259A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-07-30 1994-01-29 1994-07-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-07-30 1998-01-29 1998-07-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-07-30 2002-01-29 2002-07-31 $7700.00 Window Closed / Lapsed

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