US4293344A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Setting retardatives for compositions with a gypsum plaster base or anhydrite
Assignee: Manufacture de Produits Chimiques Protex SARL
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Filing: 1979-11-06
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Granted: 1981-10-06
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Expires: 1999-11-06
Abstract
Abstract A plaster composition is disclosed having a long setting time, which composition comprises a gypsum-based plaster and an effective amount of a setting retarding agent comprising a polymer having a molecular weight of less than 1000 of the formula: ##STR1## wherein R 1 is hydrogen or methyl, R 2 is COOH, COOR 4 , wherein R 4 is C 1 to C 4 alkyl, CONH 2 or CN, R 3 is hydrogen or methyl, X is a sodium, potassium, lithium, calcium, magnesium, or ammonium ion, and x and y designate the molar ratio of the two monomers forming the setting retarding agent of the formula I.
Inventors
- 👤 Christian M. Joseph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:55
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/14; C04B24/00; C04B24/24; C04B24/26; C04B24/2641; C04B28/16; C04B2103/00; C04B2103/20; C04B2103/22
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
166 words
A plaster composition having a long setting time which comprises a gypsum-based plaster and 0.001-2 percent of a polymer having a molecular weight of less than 1000 of the formula I, as a setting retarding agent: ##STR7## wherein R 1 is hydrogen or methyl, R 2 is --COOH, COOR 4 wherein R 4 is C 1 to C 4 alkyl, --CONH 2 , or --CN, R 3 is hydrogen or methyl, X is a sodium, potassium, lithium, calcium, magnesium, or ammonium ion, and x and y designate the molar ratio of the two monomers forming the setting retarding agent of the formula I, so that x indicates that 0 to 40 moles of the monomer of the formula II ##STR8## are present per 100 moles of the setting retarding agent of the formula I and so that y indicates that 60 to 100 moles of the monomer of the formula III ##STR9## are present per 100 moles of the setting retarding agent of the formula I.
Claim 2
Dependent Claim
166 words
A plaster composition having a long setting time which comprises a gypsum-based plaster and 0.001-2 percent of a polymer having a molecular weight of less than 1000 of the formula I, as a setting retarding agent: ##STR7## wherein R 1 is hydrogen or methyl, R 2 is --COOH, COOR 4 wherein R 4 is C 1 to C 4 alkyl, --CONH 2 , or --CN, R 3 is hydrogen or methyl, X is a sodium, potassium, lithium, calcium, magnesium, or ammonium ion, and x and y designate the molar ratio of the two monomers forming the setting retarding agent of the formula I, so that x indicates that 0 to 40 moles of the monomer of the formula II ##STR8## are present per 100 moles of the setting retarding agent of the formula I and so that y indicates that 60 to 100 moles of the monomer of the formula III ##STR9## are present per 100 moles of the setting retarding agent of the formula I.
Claim 3
Dependent Claim
22 words
The plaster composition defined in claim 1 wherein the polymer of the formula I has a molecular weight of 500 to 800.
Claim 4
Dependent Claim
46 words
The plaster composition defined in claim 1 wherein the monomer of the formula II is selected from the group consisting of acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, acrylamide, methacrylamide, acrylonitrile, and methacrylonitrile.
Claim 5
Dependent Claim
84 words
The plaster composition defined in claim 1 wherein the monomer of the formula III is selected from the group consisting of the sodium salt of acrylic acid, potassium salt of acrylic acid, lithium salt of acrylic acid, calcium salt of acrylic acid, sodium salt of methcrylic acid, potassium salt of the methacrylic acid, lithium salt of methacrylic acid, calcium salt of methacrylic acid, magnesium salt of methacrylic acid, ammonium salt of methacrylic acid, magnesium salt of acrylic acid and ammonium salt of acrylic acid.
Claim 6
Dependent Claim
31 words
The plaster composition defined in claim 1 wherein the polymer of formula I includes R 2 as --COOH or --COOR 4 wherein R 4 is C 1 to C 4 alkyl.
Claim 7
Dependent Claim
18 words
The plaster composition defined in claim 1 wherein the polymer of formula I includes R 2 as --COOH.
Claim 8
Dependent Claim
34 words
The plaster composition defined in claim 1 which further comprises at least one auxiliary agent selected from the group consisting of dispersing agents, foaming agents, water reducing agents, water-proofing agents, fungicides and coloring agents.
Claim 9
Dependent Claim
26 words
The plaster composition defined in claim 1 wherein the setting retarding agent constitutes between 0.005 and 1 per cent of the amount of the gypsum-based plaster.
Claim 10
Dependent Claim
31 words
A process for increasing the setting time of gypsum-based plaster which comprises the step of adding to said gypsum-based plaster 0.001-2 percent of the setting retarding agent defined in claim 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) | 1984-10-05 | 1985-04-06 | 1985-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-05 | 1989-04-06 | 1989-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-05 | 1993-04-06 | 1993-10-06 | $7700.00 | Window Closed / Lapsed |