A gypsum fiber board produced in a Siempelkamp dry-process, comprising 75 wt % to 90 wt % (relative to the total dry mix) of calcium sulfate hemi-hydrate and 10 wt % to 25 wt % (relative to the total dry mix) paper fibers, wherein the calcium sulfate hemi-hydrate is a mixture of α-calcium sulfate hemi-hydrate and β-calcium sulfate hemi-hydrate, wherein the content of α-calcium sulfate hemi-hydrate in the mixture is at least 5 wt % (relative to the total calcium sulfate hemi-hydrate) is disclosed. Also disclosed is a method for producing a gypsum fiber board of a thickness of 23 mm in a Siempelkamp dry-process.

A method of forming a coating layer on a fibrous mat to make a coated article includes depositing a coating composition on a carrier material and at least partially embedding a first major surface of a fibrous mat in the coating composition, the fibrous mat including a plurality of mat fibers. The coating composition is at least partially hardened to form a coating layer at the first major surface of the fibrous mat. A second major surface of the fibrous mat opposite the first major surface includes an uncoated portion of the plurality of mat fibers.

A method of forming a coating layer on a fibrous mat to make a coated article includes depositing a coating composition on a carrier material and at least partially embedding a first major surface of a fibrous mat in the coating composition, the fibrous mat including a plurality of mat fibers. The coating composition is at least partially hardened to form a coating layer at the first major surface of the fibrous mat. A second major surface of the fibrous mat opposite the first major surface includes an uncoated portion of the plurality of mat fibers.

A gypsum fiber board produced in a Siempelkamp dry-process, comprising 75 wt % to 90 wt % (relative to the total dry mix) of calcium sulfate hemi-hydrate and 10 wt % to 25 wt % (relative to the total dry mix) paper fibers, wherein the calcium sulfate hemi-hydrate is a mixture of -calcium sulfate hemi-hydrate and -calcium sulfate hemi-hydrate, wherein the content of -calcium sulfate hemi-hydrate in the mixture is at least 5 wt % (relative to the total calcium sulfate hemi-hydrate) is disclosed. Also disclosed is a method for producing a gypsum fiber board of a thickness of 23 mm in a Siempelkamp dry-process.

A gypsum fiber board produced in a Siempelkamp dry-process, comprising 75 wt % to 90 wt % (relative to the total dry mix) of calcium sulfate hemi-hydrate and 10 wt % to 25 wt % (relative to the total dry mix) paper fibers, wherein the calcium sulfate hemi-hydrate is a mixture of -calcium sulfate hemi-hydrate and -calcium sulfate hemi-hydrate, wherein the content of -calcium sulfate hemi-hydrate in the mixture is at least 5 wt % (relative to the total calcium sulfate hemi-hydrate) is disclosed. Also disclosed is a method for producing a gypsum fiber board of a thickness of 23 mm in a Siempelkamp dry-process.