JPS5523020A - Manufacture of alpha-type hemihydrate gypsum - Google Patents

Manufacture of alpha-type hemihydrate gypsum

Info

Publication number
JPS5523020A
JPS5523020A JP9443678A JP9443678A JPS5523020A JP S5523020 A JPS5523020 A JP S5523020A JP 9443678 A JP9443678 A JP 9443678A JP 9443678 A JP9443678 A JP 9443678A JP S5523020 A JPS5523020 A JP S5523020A
Authority
JP
Japan
Prior art keywords
gypsum
type hemihydrate
hemihydrate gypsum
seed
fibrous
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP9443678A
Other languages
Japanese (ja)
Inventor
Toyoitsu Shimizu
Tsuneo Ishikawa
Takao Awazu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ishihara Sangyo Kaisha Ltd
Original Assignee
Ishihara Sangyo Kaisha Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ishihara Sangyo Kaisha Ltd filed Critical Ishihara Sangyo Kaisha Ltd
Priority to JP9443678A priority Critical patent/JPS5523020A/en
Publication of JPS5523020A publication Critical patent/JPS5523020A/en
Pending legal-status Critical Current

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  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

PURPOSE: To stably obtain high quality α-type hemihydrate gypsum without unevenness in characteristics by adding fibrous α-type hemihydrate gypsum as a seed and maleic acid or a salt thereof as a habit modifier to a gypsum slurry followed by heating under press.
CONSTITUTION: To a gypsum slurry are added fibrous α-type hemihydrate gypsum of 1W5μ minor axis and 100W200μ major axis as a seed in an amt. of 0.02W0.2, pref. 0.05W0.1 part by wt. to 100 parts of gypsum and maleic acid or a salt thereof as a habit modifier in an amt. of 0.05W0.1, pref. 0.06W0.08 part to 100 parts of gypsum. The slurry is then heated under press. for 0.5W3hr at 120W140°C to convert the gypsum into α-type hemihydrate gypsum. The fibrous seed is obtd. by heating gypsum at 120W150°C under press. for about 1.5hr in the absence of a habit modifier.
COPYRIGHT: (C)1980,JPO&Japio
JP9443678A 1978-08-02 1978-08-02 Manufacture of alpha-type hemihydrate gypsum Pending JPS5523020A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9443678A JPS5523020A (en) 1978-08-02 1978-08-02 Manufacture of alpha-type hemihydrate gypsum

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9443678A JPS5523020A (en) 1978-08-02 1978-08-02 Manufacture of alpha-type hemihydrate gypsum

Publications (1)

Publication Number Publication Date
JPS5523020A true JPS5523020A (en) 1980-02-19

Family

ID=14110193

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9443678A Pending JPS5523020A (en) 1978-08-02 1978-08-02 Manufacture of alpha-type hemihydrate gypsum

Country Status (1)

Country Link
JP (1) JPS5523020A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4965031A (en) * 1989-02-24 1990-10-23 The Celotex Corporation Continuous production of gypsum board

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4965031A (en) * 1989-02-24 1990-10-23 The Celotex Corporation Continuous production of gypsum board

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