Patent US3734697A successfully refreshed from Google Patents.
Patent US4450873A successfully refreshed from Google Patents.
US4450873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reinforced plastic composite structure
Assignee: Johns Manville
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Filing: 1979-05-29
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Granted: 1984-05-29
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Expires: 1999-05-29
Abstract
Abstract A reinforced plastic composite structure, particularly a pipe, is disclosed herein. The composite pipe, which resists acid attack even in underground applications where the pipe is subjected to external loading stresses, typically includes at least an inner zone, e.g. a resin impregnated fibrous sheet and an outer zone including a layer or layers of fibers. A cured polymeric resin matrix bonds the fibrous sheet and the fibrous layers together in a laminar relationship. The improvement disclosed herein comprises incorporating into this polymeric resin matrix a particulate substance which has specific particle size limitations and which is selected from the group consisting of portland cement, marble dust or a mixture thereof.
Inventors
- 👤 Thomas H. Sadler
- 👤 John J. Dalton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:13
CPC Classifications
F; F16; F16L; F16L9/00; F16L9/16; B; B29; B29C; B29C53/00; B29C53/56; B29C53/58; B29C53/583; B29C70/00; B29C70/02; B29C70/021; B29C70/025; B29K; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/10; B29K2105/101; B29K2105/16; B29K2709/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
68 words
In a reinforced plastic composite structure having a cured polymeric resin matrix which includes at least one layer of fibers, the improvement comprising: a particulate substance selected from the group consisting of portland cement, marble dust or mixtures thereof incorporated and dispersed throughout said resin matrix at least about 80% of said particulate substance having an equivalent spherical diameter in the range of about 10 to 70 microns.
Claim 2
Dependent Claim
68 words
In a reinforced plastic composite structure having a cured polymeric resin matrix which includes at least one layer of fibers, the improvement comprising: a particulate substance selected from the group consisting of portland cement, marble dust or mixtures thereof incorporated and dispersed throughout said resin matrix at least about 80% of said particulate substance having an equivalent spherical diameter in the range of about 10 to 70 microns.
Claim 3
Dependent Claim
30 words
A composite structure according to claim 1 wherein at least about 65% of said particulate substance has an equivalent spherical diameter in the range of about 10 to 40 microns.
Claim 4
Dependent Claim
23 words
A composite structure according to claim 1 wherein said particulate substance comprises 40 to 60 percent by weight of the total resin matrix.
Claim 5
Dependent Claim
84 words
In a reinforced plastic composite pipe having a cured polyester resin matrix which includes an inner layer of a polyester veil cloth and at least one layer of glass fibers wrapped concentrically around said inner layer, the improvement comprising: a particulate substance selected from the group consisting of portland cement, marble dust or mixtures thereof incorporated and dispersed throughout said resin matrix, at least about 80% of said particulate substance having an equivalent spherical diameter in the range of about 10 to 70 microns.
Claim 6
Dependent Claim
84 words
In a reinforced plastic composite pipe having a cured polyester resin matrix which includes an inner layer of a polyester veil cloth and at least one layer of glass fibers wrapped concentrically around said inner layer, the improvement comprising: a particulate substance selected from the group consisting of portland cement, marble dust or mixtures thereof incorporated and dispersed throughout said resin matrix, at least about 80% of said particulate substance having an equivalent spherical diameter in the range of about 10 to 70 microns.
Claim 7
Dependent Claim
32 words
A reinforced plastic composite pipe according to claim 4 wherein at least about 65% of said particulate substance has an equivalent spherical diameter in the range of about 10 to 40 microns.
Claim 8
Dependent Claim
24 words
A reinforced plastic composite pipe according to claim 5 wherein said particulate substance comprises 40 to 60 weight percent of the total resin matrix.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-29 | 1987-11-28 | 1988-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-29 | 1991-11-28 | 1992-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-29 | 1995-11-28 | 1996-05-29 | $7700.00 | Window Closed / Lapsed |