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US3986997A Expired / Lapsed US ⏱️ 0.0 years remaining

Pigment-free coating compositions

Assignee: Dow Silicones Corp
•
Filing: 1974-06-25
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Granted: 1976-10-19
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Expires: 1994-06-25
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Abstract

Abstract An acidic dispersion of colloidal silica and hydroxylated silsesquioxane in an alcohol-water medium is coated onto solid substrates, such as acrylic lenses, to provide an abrasion resistant coating.

Inventors

  • 👤 Harold A. Clark

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 19:12
CPC Classifications
C; C09; C09D; C09D1/00; B; B29; B29D; B29D11/00; B29D11/00865; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C09D183/00; C09D183/04; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31507

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 119 words
A pigment-free aqueous coating composition comprising a dispersion of colloidal silica in 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 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl 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 3.0 to 6.0.
Claim 2
Dependent Claim 119 words
A pigment-free aqueous coating composition comprising a dispersion of colloidal silica in 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 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl 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 3.0 to 6.0.
Claim 3
Dependent Claim 38 words
A coating composition in accordance with claim 1 in which the alcohol in the alcohol-water cosolvent is present in a amount in the range of 20 to 75 weight percent based on the total weight of the cosolvent.
Claim 4
Dependent Claim 18 words
A composition in accordance with claim 2 wherein at least 50 weight percent of the alcohol is isopropanol.
Claim 5
Dependent Claim 31 words
A composition in accordance with claim 2 wherein the alcohol-water cosolvent contains a water-miscible polar solvent in an amount up to 20 weight percent based on the weight of suspending medium.
Claim 6
Dependent Claim 13 words
A composition in accordance with claim 4 wherein the polar solvent is acetone.
Claim 7
Dependent Claim 29 words
A composition in accordance with claim 2 wherein the acid is water-miscible organic acid selected from the group consisting of acetic acid, formic acid, propanoic acid and maleic acid.
Claim 8
Dependent Claim 22 words
A composition in accordance with claim 6 containing from about 0.05 to 1.5 weight percent of a buffered latent silanol condensation catalyst.
Claim 9
Dependent Claim 21 words
a composition in accordance with claim 7 containing a sodium catalyst as the sodium salt of the water miscible organic acid.
Claim 10
Dependent Claim 18 words
A composition in accordance with claim 7 containing as the catalyst a carboxylic acid salt of an amine.
Claim 11
Dependent Claim 15 words
A composition in accordance with claim 7 containing as the catalyst a quaternary ammonium salt.
Claim 12
Dependent Claim 14 words
A composition in accordance with claim 10 wherein the salt is benzyltrimethyl ammonium acetate.
Claim 13
Dependent Claim 18 words
A composition in accordance with claim 6 wherein the partial condensate is of CH 3 Si(OH) 3 .
Claim 14
Dependent Claim 30 words
A compositon in accordance with claim 12 wherein said partial condensate is present in an amount in the range of from 40 to 60 weight percent of the total solids.
Claim 15
Dependent Claim 19 words
A compositon in accordance with claim 13 wherein the lower aliphatic alcohol is a mixture of mehthanol and isopropanol.

References Cited (Backward Citations)

US2610167A Cited
US2568384A Cited
US2786042A Cited
US3435001A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-10-19 1980-04-19 1980-10-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-10-19 1984-04-19 1984-10-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-10-19 1988-04-19 1988-10-19 $7700.00 Window Closed / Lapsed

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