US5108679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of concrete building products
Assignee: Redland Roof Tiles Ltd
•
Filing: 1990-11-02
•
Granted: 1992-04-28
•
Expires: 2010-11-02
Abstract
Abstract A process for the production of concrete roofing products of reduced weight loading having a thickness in section of not greater than 15 mm. The process involves forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water and (iv) reinforcing fibers in an amount of not more than 4% by weight of the total weight of the composition but the fibers being present in an amount sufficient to provide a reinforcing effect and impact strength in the roofing product, the cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping the cementitious composition by the method to provide a shaped extrudate, dividing the extrudate to form sections and curing the sections to provide roofing products, wherein the reinforcing fibers have lengths of 0.5 mm to 20 mm. The impact resistant roofing products are useful as roofing tiles, or a replacement for shingles, shakes and slates.
Inventors
- 👤 Eric Rirsch
- 👤 Jeremy Wingfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:56
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/02; E; E04; E04D; E04D1/00; E04D1/02; E04D1/04; E04D1/12; E04D1/16; C04B2111/00; C04B2111/00034; C04B2111/00129; C04B2111/00474; C04B2111/00586; C04B2111/00594; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91; Y10; Y10S; Y10S264/00; Y10S264/31; Y10S264/49
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
166 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water and (iv) reinforcing fibres in an amount of not more than 4% by weight of a total weight of said composition and said fibres being present in an amount sufficient to provide a reinforcing effect, high flexural strength and high impact strength in said roofing products, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 0.5 mm to 20 mm.
Claim 2
Dependent Claim
166 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water and (iv) reinforcing fibres in an amount of not more than 4% by weight of a total weight of said composition and said fibres being present in an amount sufficient to provide a reinforcing effect, high flexural strength and high impact strength in said roofing products, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 0.5 mm to 20 mm.
Claim 3
Dependent Claim
17 words
A process as claimed in claim 1 wherein said composition additionally comprises a plasticiser or a superplasticiser.
Claim 4
Dependent Claim
20 words
A process as claimed in claim 1 in which an aspect ratio of said fibres is from 10 to 5000.
Claim 5
Dependent Claim
31 words
A process as claimed in claim 1 wherein said composition further comprises from 1 to 30% silica fume calculated as a percentage on a weight of hydraulic cement in said composition.
Claim 6
Dependent Claim
20 words
A process as claimed in claim 1 wherein particle size of said lightweight aggregate is from 0.5 to 1.50 mm.
Claim 7
Dependent Claim
22 words
A process as claimed in claim 1 wherein a weight ratio of water:hydraulic cement in said composition is from 0.15:1 to 0.90:1.
Claim 8
Dependent Claim
22 words
A process as claimed in claim 1 wherein a weight ratio of water:hydraulic cement in said composition is from 0.5:1 to 0.7:1.
Claim 9
Dependent Claim
15 words
A process as claimed in claim 1 wherein said composition is cured using an autoclave.
Claim 10
Dependent Claim
16 words
A process as claimed in claim 1 further comprising shaping said composition to provide roof tiles.
Claim 11
Dependent Claim
16 words
A process as claimed in claim 1 further comprising shaping said composition to form roof slates.
Claim 12
Dependent Claim
27 words
A process as claimed in claim 1 wherein said percentage by weight of reinforcing fibres to said total weight of said composition is from 0.15% to 1%.
Claim 13
Dependent Claim
30 words
A process as claimed in claim 11 wherein said percentage by weight of reinforcing fibres to said total weight of said composition is preferably in a range 0.15 to 0.35%.
Claim 14
Dependent Claim
14 words
A process as claimed in claim 1 wherein said reinforcing fibres are polypropylene fibers.
Claim 15
Dependent Claim
20 words
A process as claimed in claim 10 in which as aspect ratio of said fibres is from 10 to 600.
Claim 16
Dependent Claim
19 words
A process as claimed in claim 1 wherein said lightweight aggregate is a mixture of lightweight and non-lightweight aggregates.
Claim 17
Dependent Claim
21 words
A process as claimed in claim 15 in which up to 30% of said lightweight aggregate by weight is non-lightweight aggregate.
Claim 18
Dependent Claim
23 words
A process as claimed in claim 1 wherein a weight ratio of lightweight aggregate:hydraulic cement in said composition is from 1:1 to 4:1.
Claim 19
Dependent Claim
21 words
A process as claimed in claim 17 wherein said weight ratio of lightweight aggregate:hydraulic cement in said composition is substantially 2:1.
Claim 20
Dependent Claim
20 words
A process as claimed in claim 1 wherein said reinforcing fibres have lengths of from 4 mm to 8 mm.
Claim 21
Dependent Claim
20 words
A process as claimed in claim 19 in which an aspect ratio of said fibres is from 18 to 4000.
Claim 22
Dependent Claim
18 words
A process as claimed in claim 19 wherein said length of said reinforcing fibres is substantially 6 mm.
Claim 23
Dependent Claim
20 words
A process as claimed in claim 21 in which an aspect ratio of said fibres is from 20 to 3000.
Claim 24
Dependent Claim
190 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water, (iv) reinforcing fibres in an amount of not more than 4% by weight of a total weight of said composition and said fibres being present in an amount sufficient to provide a reinforcing effect, high flexural strength and high impact strength in said roofing products, and (v) a polymer latex in weight ratio of polymer, calculated as dry weight, to said hydraulic cement within a range of 5:100 to 50:100, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to product said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 0.5 mm to 20 mm.
Claim 25
Dependent Claim
190 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water, (iv) reinforcing fibres in an amount of not more than 4% by weight of a total weight of said composition and said fibres being present in an amount sufficient to provide a reinforcing effect, high flexural strength and high impact strength in said roofing products, and (v) a polymer latex in weight ratio of polymer, calculated as dry weight, to said hydraulic cement within a range of 5:100 to 50:100, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to product said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 0.5 mm to 20 mm.
Claim 26
Dependent Claim
25 words
A process as claimed in claim 23 wherein said weight ratio of polymer, calculated as dry weight, to hydraulic cement is from 2:100 to 15:100.
Claim 27
Dependent Claim
25 words
A process as claimed in claim 23 wherein said weight ratio of polymer, calculated as dry weight, to hydraulic cement is from 3:100 to 5:100.
Claim 28
Dependent Claim
138 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water and (iv) reinforcing fibres in weight percent to a total weight of said composition of 0.15% to 4%, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 2.0 mm to 20 mm.
Claim 29
Dependent Claim
138 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water and (iv) reinforcing fibres in weight percent to a total weight of said composition of 0.15% to 4%, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 2.0 mm to 20 mm.
Claim 30
Dependent Claim
162 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water, (iv) reinforcing fibers in weight percent to a total weight of said composition of 0.15% to 4%, and (v) a polymer latex in weight ratio of polymer, calculated as dry weight, to said hydraulic cement within a range of 5:100 to 50:100, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 2.0 mm to 20 mm.
Claim 31
Dependent Claim
162 words
A process for production of concrete roofing products of reduced weight loading having high flexural strength and high impact strength and a thickness in section of not greater than 15 mm which process comprises forming an asbestos-free cementitious composition comprising (i) lightweight aggregate, (ii) hydraulic cement, (iii) water, (iv) reinforcing fibers in weight percent to a total weight of said composition of 0.15% to 4%, and (v) a polymer latex in weight ratio of polymer, calculated as dry weight, to said hydraulic cement within a range of 5:100 to 50:100, said formed cementitious composition being capable of being shaped by a roller and slipper method, and thereafter shaping said formed cementitious composition by said roller and slipper method to produce a shaped extrudate, dividing said extrudate to form sections and curing said sections to produce said roofing products of reduced weight loading having high flexural strength and high impact strength, wherein said reinforcing fibres have lengths of 2.0 mm to 20 mm.
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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) | 1995-04-28 | 1995-10-28 | 1996-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-04-28 | 1999-10-28 | 2000-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-04-28 | 2003-10-28 | 2004-04-28 | $7700.00 | Window Closed / Lapsed |