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US 4,070,311 AGranted
Flameproof material or conglomerate
OwnerAdolphe Cominassi, Henri Lievremontinventors
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Abstract
An expanded material or conglomerate exhibiting outstanding fire-retardant properties and having an elevated specific weight contains 20 to 80% by weight of a binder constituted by a phenol-formaldehyde resin, 20 to 80% by weight of a gypsum obtained as a by-product in the preparation of phosphoric acid, and possibly inert filler materials which may be constituted by inorganic or organic substances.
Claims14
An expanded material or conglomerate comprising:
- 20-80% by weight of a binder comprising a phenol-formaldehyde resin, and 20-80% by weight of the sulfuric acid residue-containing, synthetically produced calcium sulfate known as phospho-gypsum, said phospho-gypsum being the reaction product of the components comprising sulfuric acid and fluorine-containing calcium phosphate rock, said fluorine-containing calcium phosphate rock containing, by weight, 1.8-4.2% F and at least 0.1% of Al.sub. 2 0.sub.3 or Fe.sub.2 0.sub.3, and said phospho-gypsum having a pH less than natural gypsum and containing more than 0.5% by weight of F and phosphate residues from said phosphate rock.
In a method for manufacturing an expanded material or conglomerate comprising the steps of:
- a. feeding under pressure to a first mixing zone a phenol-formaldehyde resin and at least one expansion agent to obtain a first mixture, comprising 20 to 80% by weight phenol-formaldehyde resin,
- b. feeding said first mixture to a second mixing zone while simultaneously feeding a catalyst to said second mixing zone, whereby simultaneous polymerization and expansion are initiated in said second mixing zone,
- the improvement which comprises the steps of:
- obtaining the acid residue-containing synthetically produced calcium sulfate known as phospho-gypsum, in powder form, and
- including 20-80% by weight of said phospho-gypsum in said first mixture as a fire-retarding additive;
- said phospho-gypsum having a pH less than about 3 and containing more than 0.5 weight-% F and more than 0.5 weight-% residual phosphate.
3 more elements
Dependencies are inferred from the claim text.