US4191804A
Expired / Lapsed
US
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Coating composition
Assignee: Aotec Inc
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Filing: 1978-06-30
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Granted: 1980-03-04
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Expires: 1998-06-30
Abstract
Abstract An improved pigment-free abrasion resistant coating composition for plastic substrates which is particularly suited for the protective coating of optical lenses formed from synthetic polymers such as acrylics, polyesters, polycarbonates, and the like. The coating composition is characterized by significantly improved adhesive qualities over prior art materials. The composition includes a major amount of a pigment-free aqueous composition comprising a dispersion of colloidal silica in a lower aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH) 3 in which R is selected from the group consisting of alkyl radicals of 1 to 3 inclusive carbons, the vinyl radical, cyanoethyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical, at least 70 weight percent of the silanol being CH 3 Si(OH) 3 , said composition containing 10 to 50 weight percent solids consisting essentially of 10 to 70 weight percent colloidal silica and 30 to 90 weight percent of the partial condensate, said composition containing sufficient acid to provide a pH in the range of about 3 to about 6; and, based on the above solids from about 3.5% to about 20% by weight of a pigment-free resin selected from the group consisting of amino resins and amino resins which have been at least partially alkylated with at least one aliphatic alcohol having from 1 to 8 carbons and mixtures thereof. Examples of resins to be added to the partial silanol condensate and colloidal silica composition are urea-formaldehyde resins, melamine-formaldehyde resins and the corresponding methylated resins. The invention also includes plastic materials having the above cured coating compositions thereon.
Inventors
- 👤 Hermann P. Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:57
CPC Classifications
C; C09; C09D; C09D183/00; C09D183/04; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; C08J7/043; C08J7/046; C08J2483/00; Y; Y10; Y10T; Y10T428/00; Y10T428/31; Y10T428/31504; Y10T428/31507; Y10T428/31652; Y10T428/31663; Y10T428/31855; Y10T428/31859; Y10T428/31862; Y10T428/3187; Y10T428/31873
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
191 words
In a coating composition which comprises: a pigment-free aqueous composition comprising a dispersion of colloidal silica in a lower aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH) 3 in which R is selected from the group consisting of alkyl radicals of 1 to 3 inclusive carbons, the vinyl radical, the cyanoethyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical, at least 70 weight percent of the silanol being CH 3 Si(OH) 3 , said composition containing 10 to 50 weight percent solids consisting essentially of 10 to 70 weight percent colloidal silica and 30 to 90 weight percent of the partial condensate, said composition containing sufficient acid to provide a pH in the range of about 3.0 to about 6.0; the improvement which comprises: from about 3.5 percent to about 20 percent by weight based on the solids content of the silica-silanol dispersion of a pigment-free resin selected from the group consisting of amino resins and amino resins which have been at least partially alkylated with at least one aliphatic alcohol having from 1-8 carbons, and mixtures thereof, said resin being dispersible in said silica-silanol dispersion.
Claim 2
Dependent Claim
191 words
In a coating composition which comprises: a pigment-free aqueous composition comprising a dispersion of colloidal silica in a lower aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH) 3 in which R is selected from the group consisting of alkyl radicals of 1 to 3 inclusive carbons, the vinyl radical, the cyanoethyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical, at least 70 weight percent of the silanol being CH 3 Si(OH) 3 , said composition containing 10 to 50 weight percent solids consisting essentially of 10 to 70 weight percent colloidal silica and 30 to 90 weight percent of the partial condensate, said composition containing sufficient acid to provide a pH in the range of about 3.0 to about 6.0; the improvement which comprises: from about 3.5 percent to about 20 percent by weight based on the solids content of the silica-silanol dispersion of a pigment-free resin selected from the group consisting of amino resins and amino resins which have been at least partially alkylated with at least one aliphatic alcohol having from 1-8 carbons, and mixtures thereof, said resin being dispersible in said silica-silanol dispersion.
Claim 3
Dependent Claim
25 words
An improved coating composition as claimed in claim 1 wherein: about 20 to about 75 weight percent of the alcohol-water cosolvent is comprised of alcohol.
Claim 4
Dependent Claim
20 words
An improved coating composition as claimed in claim 2 wherein: at least 50 weight percent of the alcohol is isopropanol.
Claim 5
Dependent Claim
28 words
An improved coating composition as claimed in claim 2 wherein: said alcohol-water cosolvent system further includes up to about 20 weight percent of a water miscible polar solvent.
Claim 6
Dependent Claim
29 words
An improved coating composition as claimed in claim 2 wherein: said acid is a water-miscible organic acid selected from the group consisting of acetic, formic, propanoic and maleic acids.
Claim 7
Dependent Claim
26 words
An improved coating composition as claimed in claim 5 further comprising: from about 0.05 to about 1.5 weight percent of a buffered latent silanol condensation catalyst.
Claim 8
Dependent Claim
20 words
An improved coating composition as claimed in claim 5 wherein: the partial condensate is of CH 3 Si(OH) 3 .
Claim 9
Dependent Claim
66 words
An improved coating composition as claimed in claims 2 or 7 wherein: said partial condensate is present in an amount in the range of from about 40 to about 60 weight percent of the solids content of the silica-silanol dispersion; and wherein, said resin is a urea-formaldehyde resin which has been at least partially alkylated with an aliphatic alcohol having from 1 to 4 carbon atoms.
Claim 10
Dependent Claim
71 words
An improved coating composition as claimed in claims 2 or 7 wherein: said partial condensate of a silanol is present in an amount in the range of from about 40 to about 60 weight percent of the total solids of said silica-silanol dispersion; and wherein, said resin is a melamine-formaldehyde resin which has been at least partially alkylated with at least one aliphatic alcohol having from 1 to 4 carbon atoms.
Claim 11
Dependent Claim
27 words
An improved coating composition as claimed in claim 8 wherein: the lower aliphatic alcohol of the alcohol-water cosolvent system is a mixture of methanol, isopropanol, and n-butanol.
Claim 12
Dependent Claim
51 words
An improved coating composition as claimed in claims 2 or 7 wherein: said partial condensate of a silanol is present in an amount in the range of from about 40 to about 60 weight percent of the total solids of said silica-silanol dispersion; and wherein, said resin is a melamine-formaldehyde resin.
Claim 13
Dependent Claim
51 words
An improved coating composition as claimed in claims 2 or 7 wherein: said partial condensate of a silanol is present in an amount in the range of from about 40 to about 60 weight percent of the total solids of said silica-silanol dispersion; and wherein, said resin is a urea-formaldehyde resin.
Claim 14
Dependent Claim
71 words
An improved coating composition as claimed in claims 2 or 7 wherein: said partial condensate of said silanol is present in an amount in the range of from about 40 to about 60 weight percent of the total solids of said silica-silanol dispersion; and wherein, said resin is a benzoguanamine resin which has been at least partially alkylated with at least one aliphatic alcohol having from 1 to 4 carbon atoms.
Claim 15
Dependent Claim
19 words
A synthetic plastic surface having thereon a cured continuous coating of the coating composition as claimed in claim 1.
Claim 16
Dependent Claim
17 words
A plastic surface having thereon a cured continuous coating of the composition as claimed in claim 9.
Claim 17
Dependent Claim
18 words
A polycarbonate surface having thereon a cured continuous coating of the coating composition as claimed in 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) | 1983-03-04 | 1983-09-03 | 1984-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-04 | 1987-09-03 | 1988-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-04 | 1991-09-03 | 1992-03-04 | $7700.00 | Window Closed / Lapsed |