US4328178A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of producing a building product of gypsum, particularly a gypsum slab
Assignee: Individual
•
Filing: 1980-05-12
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Granted: 1982-05-04
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Expires: 2000-05-12
Abstract
Abstract This invention provides a process of producing a building product, particularly a gypsum slab having preferably a density of below 800 kg/m 3 , with gypsum and mixing water. The quantity of mixing water required for rehydration and molding is at least substantially completely introduced into the gypsum by means of water saturated porous particles added in a distributed form. The process comprises the steps of intimately mixing water saturated particles with pulverous gypsum to form a fluid mixture; converting said fluid mixture at least almost completely without the application of pressure to the shape of a gypsum building product; permitting mixing water of the water saturated particles to be absorbed by the pulverous gypsum, and permitting the resulting mixture to set and harden.
Inventors
- 👤 Gert Kossatz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:18
CPC Classifications
C; C04; C04B; C04B20/00; C04B20/10; C04B20/1055; C04B28/00; C04B28/14
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
180 words
A semi-dry process of producing a building product, particularly a gypsum slab having a density below 800 kg/m 3 , with gypsum and mixing water, wherein the quantity of mixing water required for rehydration and molding is at least substantially completely introduced into the gypsum by means of water saturated porous filler particles added in a distributed form, said process comprising the steps of: (a) wetting particles consisting predominately of porous filler until they are just substantially saturated and intimately mixing the water saturated filler particles with pulverous calcined gypsum to form a fluid particulate mixture, the amount of water contained in said water saturated particles being limited to assure formation of said fluid particulate mixture and hydration of said calcined gypsum but being insufficient to form a pulpy-liquid phase mixture; (b) forming said fluid particulate mixture, at least almost completely without the application of pressure, into the shape of a gypsum building product; (c) permitting mixing water of the water saturated particles to be absorbed by the pulverous gypsum, and (d) permitting the resulting mixture to set and harden.
Claim 2
Dependent Claim
180 words
A semi-dry process of producing a building product, particularly a gypsum slab having a density below 800 kg/m 3 , with gypsum and mixing water, wherein the quantity of mixing water required for rehydration and molding is at least substantially completely introduced into the gypsum by means of water saturated porous filler particles added in a distributed form, said process comprising the steps of: (a) wetting particles consisting predominately of porous filler until they are just substantially saturated and intimately mixing the water saturated filler particles with pulverous calcined gypsum to form a fluid particulate mixture, the amount of water contained in said water saturated particles being limited to assure formation of said fluid particulate mixture and hydration of said calcined gypsum but being insufficient to form a pulpy-liquid phase mixture; (b) forming said fluid particulate mixture, at least almost completely without the application of pressure, into the shape of a gypsum building product; (c) permitting mixing water of the water saturated particles to be absorbed by the pulverous gypsum, and (d) permitting the resulting mixture to set and harden.
Claim 3
Dependent Claim
24 words
A process as set forth in claim 1 wherein pressure is applied to said mixture in an amount less than 1.5 N/mm 2 .
Claim 4
Dependent Claim
36 words
A process as set forth in claim 2, wherein the fluid mixture is placed on a mold surface and, by shaking, is given the desired shape, particularly the desired slab thickness for the gypsum building product.
Claim 5
Dependent Claim
37 words
A process as set forth in claim 2, wherein the fluid mixture is placed on a mold surface and is smoothed down to the desired shape, particularly to the desired slab thickness for the gypsum building product.
Claim 6
Dependent Claim
37 words
A process as set forth in claim 2, wherein the fluid mixture is placed on a mold surface and is rolled down to the desired shape, particularly to the desired slab thickness for the gypsum building product.
Claim 7
Dependent Claim
48 words
A process as set forth in claim 2, wherein the fluid mixture is placed on a mold surface and is given the desired shape, particularly the desired slab thickness for the gypsum building product, by the application of a slight surface pressure, under about 1.5 N/mm 2 .
Claim 8
Dependent Claim
32 words
A process as set forth in claim 2, wherein the water-saturated porous particles consist of dihydrate grains which act as crystallization nuclei and of which the grain size is mainly 1-5 mm.
Claim 9
Dependent Claim
16 words
A process as set forth in claim 2, wherein accelerators are added to the mixing water.
Claim 10
Dependent Claim
16 words
A process as set forth in claim 2, wherein retarders are added to the mixing water.
Claim 11
Dependent Claim
51 words
A process as set forth in claim 2, wherein the mixing water is given an addition of agents selected from the group consisting of liquefiers and flow-forming agents, which reduce the surface tension of the mixing water, form a lubricating film on the surface or provide a combination of both effects.
Claim 12
Dependent Claim
17 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise comminuted gas concrete.
Claim 13
Dependent Claim
16 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise inflation clay.
Claim 14
Dependent Claim
16 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise inflation mica.
Claim 15
Dependent Claim
16 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise foam glass.
Claim 16
Dependent Claim
16 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise mineral glass.
Claim 17
Dependent Claim
18 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise synthetic resin foam flakes.
Claim 18
Dependent Claim
16 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise wood shavings.
Claim 19
Dependent Claim
19 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise wood fiber granulate and bark.
Claim 20
Dependent Claim
15 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise vermiculite.
Claim 21
Dependent Claim
15 words
A process as set forth in claim 2 wherein said water-saturated porous particles comprise perlite.
Claim 22
Dependent Claim
19 words
A process as set forth in claim 2 wherein the maximum weight ratio of water to gypsum is 0.4:1.
Claim 23
Dependent Claim
20 words
A process as set forth in claim 21 wherein the weight ratio of water to gypsum is 0.33:1 to 0.4:1.
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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) | 1985-05-03 | 1985-11-02 | 1986-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-03 | 1989-11-02 | 1990-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-03 | 1993-11-02 | 1994-05-04 | $7700.00 | Window Closed / Lapsed |