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US4645548A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing non-combustible gypsum board and non-combustible laminated gypsum board

Assignee: Taiheiyo Cement Corp
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Filing: 1985-02-05
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Granted: 1987-02-24
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Expires: 2005-02-05
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Abstract

Abstract A novel process for producing a non-combustible gypsum board and a non-combustible laminated gypsum board having superior practical physical properties, smoothly and efficiently is provided, which process is characterized by preparing a mixture consisting of a powdery gypsum consisting of 50 to 95 parts by weight of a hydrating gypsum and 5 to 50 parts by weight of gypsum dihydrate, a definite amount of fibers and a definite amount of a caking retarder and a necessary amount of water; molding the mixture before the hydrating gypsum is hydrated; and setting and drying the resulting molded material.

Inventors

  • 👤 Takao Take
  • 👤 Katsuaki Kaneko
  • 👤 Kokyo Kusunoki
  • 👤 Toshinobu Ichiba

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 15:28
CPC Classifications
B; B32; B32B; B32B13/00; B32B13/04; B28; B28B; B28B1/00; B28B1/52; B28B1/527; B32B13/02; C; C04; C04B; C04B28/00; C04B28/14; E; E04; E04C; E04C2/00; E04C2/02; E04C2/04; E04C2/043; B32B2305/00; B32B2305/77; C04B2103/00; C04B2103/20; C04B2103/22; C04B2111/00; C04B2111/00474; C04B2111/00612; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 112 words
A process for producing a non-combustible gypsum board which includes (1) preparing a mixture consisting essentially of (a) a powdery gypsum composed of 50 to 95 parts by weight of a hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate, (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum., (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum, and (d) water, and thereafter (2) molding said mixture before said hydraulic gypsum is completely hydrated, and (3) setting and drying the resulting molded material.
Claim 2
Dependent Claim 112 words
A process for producing a non-combustible gypsum board which includes (1) preparing a mixture consisting essentially of (a) a powdery gypsum composed of 50 to 95 parts by weight of a hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate, (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum., (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum, and (d) water, and thereafter (2) molding said mixture before said hydraulic gypsum is completely hydrated, and (3) setting and drying the resulting molded material.
Claim 3
Dependent Claim 24 words
A process according to claim 1 wherein said fibers are selected from the group consisting of asbestos fibers, cellulose fibers and a combination thereof.
Claim 4
Dependent Claim 17 words
A process according to claim 1 wherein said setting retarder is tartaric acid or its metal salts.
Claim 5
Dependent Claim 24 words
A process according to claim 1 wherein said setting retarder is a mixture of tartaric or its metal salts with an amino acid derivative.
Claim 6
Dependent Claim 29 words
A process according to claim 1 wherein a basic inorganic substance is added to the product of step (1) and the pH thereof is adjusted to 7 or more.
Claim 7
Dependent Claim 14 words
A process according to claim 5 wherein said basic inorganic substance is Portland cement.
Claim 8
Dependent Claim 15 words
A process according to claim 5 wherein said basic inorganic substance is powdery calcium carbonate.
Claim 9
Dependent Claim 25 words
A process according to claim 1 wherein said molding is carried out by press molding under a pressure of 10 to 500 Kg/cm 2 .
Claim 10
Dependent Claim 17 words
A process according to claim 1 wherein said molding is carried out according to the Hatschek process.
Claim 11
Dependent Claim 26 words
A process according to claim 9 wherein a green sheet obtained after said sheet-making is press-molded under a pressure of 10 to 500 Kg/cm 2 .
Claim 12
Dependent Claim 156 words
A process for producing a non-combustible laminated gypsum board which includes (1) preparing a mixture consisting essentially of (a) a powdery gypsum composed of 50 to 95 parts by weight of a hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum, and (d) water sufficient to hydrate said hydraulic gypsum, (2) making said mixture into a sheet by a cylindrical gauze type sheet-making process, (3) laminating two or more of said green-sheets before said gypsum is said green sheet is completely hydrated, (4) molding the laminated sheets under a pressure of 30 to 500 Kg/cm 2 to thereby integrate them, and (5) setting and drying the resulting molded laminate.
Claim 13
Dependent Claim 156 words
A process for producing a non-combustible laminated gypsum board which includes (1) preparing a mixture consisting essentially of (a) a powdery gypsum composed of 50 to 95 parts by weight of a hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum, and (d) water sufficient to hydrate said hydraulic gypsum, (2) making said mixture into a sheet by a cylindrical gauze type sheet-making process, (3) laminating two or more of said green-sheets before said gypsum is said green sheet is completely hydrated, (4) molding the laminated sheets under a pressure of 30 to 500 Kg/cm 2 to thereby integrate them, and (5) setting and drying the resulting molded laminate.
Claim 14
Dependent Claim 24 words
A process according to claim 11 wherein said fibers are selected from the group consisting of asbestos fibers, cellulose fibers and a combination thereof.
Claim 15
Dependent Claim 17 words
A process according to claim 11 wherein said setting retarder is tartaric acid or its metal salts.
Claim 16
Dependent Claim 34 words
A process according to claim 11 wherein a basic inorganic substance is added to the produce to step (1) and the pH of said product of step (1) is adjusted to 7 or more.
Claim 17
Dependent Claim 25 words
A process according to claim 11 wherein said setting retarder is a mixture of tartaric acid or its metal salts with an amino acid derivative.
Claim 18
Dependent Claim 87 words
A composition for producing a non-combustible gypsum board that is composed of a mixture consisting essentially of (a) a powdery gypsum that includes 50 to 95 parts by weight of hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate, (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum, and (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum.
Claim 19
Dependent Claim 87 words
A composition for producing a non-combustible gypsum board that is composed of a mixture consisting essentially of (a) a powdery gypsum that includes 50 to 95 parts by weight of hydraulic gypsum and 5 to 50 parts by weight of gypsum dihydrate, (b) 0.5 to 30 parts by weight of fibers based on 100 parts by weight of said powdery gypsum, and (c) 0.1 to 2.0 parts by weight of a setting retarder for the hydraulic gypsum based on 100 parts by weight of said hydraulic gypsum.
Claim 20
Dependent Claim 24 words
A composition according to claim 16 wherein said fibers are selected from the group consisting of asbestos fibers, cellulose fibers and a combination thereof.
Claim 21
Dependent Claim 17 words
A composition according to claim 16 wherein said setting retarder is tartaric acid or its metal salts.
Claim 22
Dependent Claim 25 words
A composition according to claim 16 wherein said setting retarder is a mixture of tartaric acid or its metal salts with an amino acid derivative.
Claim 23
Dependent Claim 28 words
A composition according to claim 16 which additionally includes a basic inorganic substance in a quantity sufficient to adjust the pH of said mixture of 7 or more.

References Cited (Backward Citations)

US3616173A Cited
JPS5119449A Cited
US4190455A Cited
JPS5325339A Cited
US4286994A Cited
JPS5536628A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-23 1990-08-25 1991-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-23 1994-08-25 1995-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-23 1998-08-25 1999-02-24 $7700.00 Window Closed / Lapsed

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