Loading patent…
AssigneeBabcock BSH Aktiengesellschaft Vormals Buttner-Schilde-Haas AG
InventorsJosef Stipek, Friedrich Bahner, Horst Hose, Karl Freisinger, Helmut Eidam
Estimating the term…
In the process for making gypsum fiberboard the boards are formed or molded rom a mash containing calcium sulfate dihydrate and fiberous material. By heating and subsequently cooling the boards the dihydrate is first converted into the hemihydrate and subsequently recrystallized again to the dihydrate. Known processes require day line setting times which are economically disadvantageous. According to the present invention these times are shortened by pulling or drawing water, an aqueous solution or a water containing mixture through the boards after the cooling step. Advantageously a setting accelerating agent can be dissolved in the water. By these features the setting time can be shortened to less than two hours. By addition of a binding agent, e.g. starch, to the fluid drawn through the boards the strength of the boards is increased.
A process for making gypsum fiberboard comprising the consecutive steps of:
Dependencies are inferred from the claim text.