Patent US4061834A successfully refreshed from Google Patents.
US4061834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Durable antistatic coating for polymethylmethacrylate
Assignee: National Aeronautics and Space Administration
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Filing: 1976-06-03
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Granted: 1977-12-06
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Expires: 1996-06-03
Abstract
Abstract A durable antistatic coating is achieved on polymethylmethacrylate plastic without affecting its optical clarity by applying to the surface of the plastic a low molecular weight solvent having a high electron affinity and a high dipole moment such as acentonitrile or nitromethane alone or in the presence of photopolymerizable monomer. The treated polymethylmethacrylate plastic can then dissipate most of the induced electrostatic charge and retains its optical clarity. The antistatic behavior persists after washing, rubbing and vacuum treatment.
Inventors
- 👤 Vaclav Hadek
- 👤 Robert B. Somoano
- 👤 Alan Rembaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:04
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/02; C08J7/12; C08J7/16; C08J7/18; C08J2333/00; C08J2333/04; C08J2333/06; C08J2333/10; C08J2333/12; Y; Y10; Y10S; Y10S260/00; Y10S260/15; Y10S428/00; Y10S428/922; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/31935
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
87 words
A method of providing a durable, optically clear, transparent, antistatic coating on the surface of a transparent solid polymethacrylate article comprising the steps of: applying to the surface of the article at a temperature of no more than 40° C a low molecular weight, polar, organic solvent having high electron affinity selected from the group consisting of nitromethane or acetonitrile, to form an antistatic coating comprising a surface layer of said article having at least 0.05% by weight of said solvent retained therein; and drying said surface.
Claim 2
Independent Claim
87 words
A method of providing a durable, optically clear, transparent, antistatic coating on the surface of a transparent solid polymethacrylate article comprising the steps of: applying to the surface of the article at a temperature of no more than 40° C a low molecular weight, polar, organic solvent having high electron affinity selected from the group consisting of nitromethane or acetonitrile, to form an antistatic coating comprising a surface layer of said article having at least 0.05% by weight of said solvent retained therein; and drying said surface.
Claim 3
Dependent Claim
25 words
A method according to claim 1 in which the article is a solid polymeric methacrylate ester selected from methyl, ethyl, propyl, butyl, or mixtures thereof.
Claim 4
Dependent Claim
15 words
A method according to claim 2 in which the solid polymeric ester is a polymethylmethacrylate.
Claim 5
Dependent Claim
19 words
A method according to claim 1 in which the article contains at least 0.1% by weight of the solvent.
Claim 6
Dependent Claim
15 words
A method according to claim 1 in which the solvent is applied at room temperature.
Claim 7
Dependent Claim
23 words
A method according to claim 5 in which the solvent is applied to the article by immersion of the article in the solvent.
Claim 8
Dependent Claim
12 words
A method according to claim 1 in which the solvent is acetonitrile.
Claim 9
Dependent Claim
10 words
An article produced according to the method of claim 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-05 | 1981-06-06 | 1981-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-05 | 1985-06-06 | 1985-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-05 | 1989-06-06 | 1989-12-06 | $7700.00 | Window Closed / Lapsed |