Patent US3972972A successfully refreshed from Google Patents.
US3972972A
Expired / Lapsed
US
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Process for producing a board of cement-like material reinforced by fibrous material and apparatus for the process
Assignee: Taiheiyo Cement Corp
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Filing: 1974-04-18
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Granted: 1976-08-03
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Expires: 1994-04-18
Abstract
Abstract This invention relates to a process for continuously producing a board of cement-like material reinforced by fibrous material, which comprises (A) preparing granules of cement-like material by adding water to powdery cement-like material; (B) preparing a granular mixture of the cement-like material and fibrous material by mixing the above prepared granules of cement-like material with short lengths of fibrous material dispersed in air; and (C) forming said granular mixture into a board under compression, optionally with the addition of water.
Inventors
- 👤 Tsuyoshi Yano
- 👤 Takao Take
- 👤 Kentaro Nakahara
- 👤 Tetsuro Sasano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:37
CPC Classifications
B; B28; B28B; B28B17/00; B28B17/02; B28B1/00; B28B1/52; B28B1/526
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
130 words
A process for continuously producing a dense board of cement-like material reinforced by fibrous material, which comprises: a. preparing granules of cement-like material having a diameter of 1 mm to 10 mm by adding water to a powdery cement-like material in the minimum amount required for granulation; b. preparing a granular mixture of the cement-like material and fibrous material by means of a pan-shaped pelletizer or a drum-type rotary system mixer by sprinkling fibrous material having a fiber length of 20 mm to 100 mm dispersed in air onto the above prepared granules of cement-like material; and c. forming said granular mixture into a board under compression with the addition of water in such an amount that the total amount of water is the minimum amount theoretically required for hydration.
Claim 2
Dependent Claim
130 words
A process for continuously producing a dense board of cement-like material reinforced by fibrous material, which comprises: a. preparing granules of cement-like material having a diameter of 1 mm to 10 mm by adding water to a powdery cement-like material in the minimum amount required for granulation; b. preparing a granular mixture of the cement-like material and fibrous material by means of a pan-shaped pelletizer or a drum-type rotary system mixer by sprinkling fibrous material having a fiber length of 20 mm to 100 mm dispersed in air onto the above prepared granules of cement-like material; and c. forming said granular mixture into a board under compression with the addition of water in such an amount that the total amount of water is the minimum amount theoretically required for hydration.
Claim 3
Dependent Claim
25 words
The process according to claim 1, wherein water is added in an amount of 25% in step (a) to prepare said granules of cement-like material.
Claim 4
Dependent Claim
29 words
A process according to claim 1, wherein said cement-like material is a member selected from the group consisting of Portland cement, alumina cement, magnesia cement, blast-furnace cement and gypsum.
Claim 5
Dependent Claim
30 words
A process according to claim 1, wherein the fibrous material is a member selected from the group consisting of glass fiber, vegetable fiber, organic fiber, wood wool, asbestos and rockwool.
Claim 6
Dependent Claim
16 words
The process according to claim 1 wherein the fiber length is between 20 and 50 millimeters.
Claim 7
Dependent Claim
16 words
A process according to claim 1 wherein the fiber content is 5 to 15% by weight.
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) | 1979-08-03 | 1980-02-02 | 1980-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-03 | 1984-02-02 | 1984-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-03 | 1988-02-02 | 1988-08-03 | $7700.00 | Window Closed / Lapsed |