Use of microcapsules in gypsum plasterboards

1. A latent heat storage article, comprising:

a plasterboard comprising at least two fibrous sheets and a gypsum plaster core between any two adjacent fibrous sheets, each gypsum plaster core containing microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of −20 to 120° C. encapsulated in a shell of a thermoset polymer.

2. The latent heat storage article as claimed in claim 1 , wherein the microcapsules have a mean particle size ranging from 0.5 to 100 μm.

3. The latent heat storage article as claimed in claim 1 , wherein the thermoset polymer is a formaldehyde resin, a polyurea, a polyurethane or a cross-linked methacrylic ester polymer.

4. The latent heat storage article as claimed in claim 1 , wherein the thermoset polymer is prepared by free-radical polymerization of a monomer mixture comprising:

from 30 to 100% by weight, based on the total weight of the monomers, of one or more C 1 –C 24 -alkyl esters of acrylic acid and/or methacrylic acid (monomer I),

from 0 to 80% by weight, based on the total weight of the monomers, of one or more bifunctional or polyfunctional monomers (monomers II) which are insoluble or sparingly soluble in water and

from 0 to 40% by weight, based on the total weight of the monomers, of other monomers (monomers III).

5. The latent heat storage article as claimed in claim 1 , wherein the amount of said microcapsules in the plasterboard ranges from 5 to 40% by weight, based on the weight of the plasterboard.

6. The latent heat storage article as claimed in claim 5 , wherein the amount of said microcapsules in the plasterboard ranges from 20 to 35% by weight.

7. The latent heat storage article as claimed in claim 1 , wherein the plasterboard has a density of 750–950 kg/m 3 .

8. The latent heat storage article as claimed in claim 1 , wherein the paperboard of the plasterboard has a thickness ranging from 0.2 to 1 mm and/or a grammage of 100 to 500 g/m 2 .

9. The latent heat storage article as claimed in claim 1 , wherein the at least two fibrous sheets are made of glass fibers.

10. The latent heat storage article as claimed in claim 1 , wherein the at least two fibrous sheets are made of polymer fibers.

11. A process for producing latent heat storage article, comprising:

introducing an aqueous slurry of plaster of Paris between two paperboard sheets having a cellulose basis, wherein the slurry of plaster of Paris of calcium sulfate hemihydrate contains microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of −20 to 120° C. encapsulated in a shell of a thermoset polymer, the weight ratio of microcapsules to calcium sulfate hemihydrate ranging from 5/95 to 40/60; and

heat treating the plasterboard that is obtained.

12. A process for producing latent heat storage article, comprising:

introducing an aqueous slurry of plaster of Paris between two glass fiber sheets, wherein the slurry of plaster of Paris of calcium sulfate hemihydrate contains microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of −20 to 120° C. encapsulated in a shell of a thermoset polymer, the weight ratio of microcapsules to calcium sulfate hemihydrate ranging from 5/95 to 40/60; and

heat treating the plasterboard that is obtained.

13. A latent heat storage article which is a plasterboard comprising at least two fibrous sheets and a gypsum plaster core between any two adjacent fibrous sheets, each gypsum plaster core consisting essentially of gypsum and microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of −20 to 120° C. encapsulated in a shell of a thermoset polymer.

14. A latent heat storage article, comprising:

a plasterboard comprising at least two fibrous sheets and a gypsum plaster core between any two adjacent fibrous sheets, each gypsum plaster core containing microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of 15 to 30° C. encapsulated in a shell of a thermoset polymer.

15. A latent heat storage article, comprising:

a plasterboard comprising at least two fibrous sheets and a gypsum plaster core between any two adjacent fibrous sheets, each gypsum plaster core containing microcapsules of at least one organic lipophilic substance having its solid/liquid phase transition in the temperature range of 30 to 60° C. encapsulated in a shell of a thermoset polymer.