US4758469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pavement markings containing transparent non-vitreous ceramic microspheres
Assignee: 3M Co
•
Filing: 1987-04-08
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Granted: 1988-07-19
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Expires: 2007-04-08
Abstract
Abstract Pavement marking comprising ceramic microspheres held by a binder, said microspheres being solid, transparent, non-vitreous, ceramic particles which serve as lens elements in the retroreflective pavement markings. The ceramic microspheres formed by various sol gel techniques are characterized by having: A. at least one metal oxide phase; and B. an average minimum dimension of up to 125 micrometers. The inventive pavement markings retain reflectivity for a surprisingly long time.
Inventors
- 👤 Roger W. Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:50
CPC Classifications
C; C08; C08K; C08K7/00; C08K7/16; C08K7/18; C04; C04B; C04B14/00; C04B14/02; C04B14/30; E; E01; E01F; E01F9/00; E01F9/50; E01F9/506; E01F9/524; E01F9/576; E01F9/578; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/252; Y10T428/259; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
41 words
A pavement marking comprising ceramic microspheres held by a binder said microspheres being solid, transparent, non-vitreous microspheres having an average particle size of up to 125 micrometers, comprising zirconia and silica, and containing at most only minor amounts of titanium dioxide.
Claim 2
Dependent Claim
41 words
A pavement marking comprising ceramic microspheres held by a binder said microspheres being solid, transparent, non-vitreous microspheres having an average particle size of up to 125 micrometers, comprising zirconia and silica, and containing at most only minor amounts of titanium dioxide.
Claim 3
Dependent Claim
20 words
The pavement marking of claim 1 wherein the mole ratio of zirconia to silica is from about 10:1 to 1:10.
Claim 4
Dependent Claim
17 words
The pavement marking of claim 1 wherein the ceramic microspheres have a haradness greater than 500 knoop.
Claim 5
Dependent Claim
37 words
The pavement marking of claim 1 which comprises sheeting having a binder film wherein the binder is a thermoplastic resin containing the ceramic microspheres both within the body of the binder and exposed at the sheeting surface.
Claim 6
Dependent Claim
57 words
The pavement marking of claim 1 which comprises a sheet material comprising: A. a base sheet selected from the group consisting of aluminum foil and polymeric sheet materials; B. a binder layer adhered to one surface of the base sheet; and C. a layer of the transparent, ceramic microspheres at least partially embedded in the binder layer.
Claim 7
Dependent Claim
43 words
The pavement marking of claim 1 which is a sheet material comprising: (i) a viscoelastic, polymeric base sheet having a multiplicity of protuberances; and (ii) a multiplicity of the transparent ceramic microspheres located on the supported by the raised surfaces of the protuberances.
Claim 8
Dependent Claim
45 words
A coating composition comprising a mixture of binder material and ceramic microspheres which are solid, transparent, non-vitreous microspheres having an average particle size of up to 125 micrometers and which are comprised of zirconia and silica and contain at most only minor amounts of titania.
Claim 9
Dependent Claim
45 words
A coating composition comprising a mixture of binder material and ceramic microspheres which are solid, transparent, non-vitreous microspheres having an average particle size of up to 125 micrometers and which are comprised of zirconia and silica and contain at most only minor amounts of titania.
Claim 10
Dependent Claim
19 words
The coating composition of claim 7 wherein the mole ratio of zirconia to silica is about 10:1 and 1:10.
References Cited (Backward Citations)
US2218909A
Cited
US2326634A
Cited
US2963378A
Cited
US3355311A
Cited
US3709706A
Cited
US3872217A
Cited
US3795524A
Cited
US3849351A
Cited
US4166147A
Cited
US4069281A
Cited
US4117192A
Cited
US4116866A
Cited
US4145112A
Cited
US4367919A
Cited
US4255286A
Cited
US4138336A
Cited
US4292035A
Cited
US4248932A
Cited
US4299874A
Cited
US4412018A
Cited
US4434076A
Cited
US4388359A
Cited
US4490432A
Cited
US4564556A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-19 | 1992-01-18 | 1992-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-19 | 1996-01-18 | 1996-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-19 | 2000-01-18 | 2000-07-19 | $7700.00 | Window Closed / Lapsed |