The invention provides an aerogel-concrete mixture, a high-performance aerogel concrete obtained therefrom, and a method for production thereof. The problem addressed by the present application is that of providing pressure-resistant but not very thermally conductive concretes, precast concrete components, screeds, screeds for precast components, (glassfibre-) reinforced concrete, fire protection panels, construction elements for thermal partition and blocks. The aerogel-concrete mixture contains: 10% to 85% by volume/m.sup.3 of aerogel pellets having a grain size in the range from 0.01 to 4 mm, 100 to 900 kg/m.sup.3 of inorganic hydraulic binder, 10% to 40% by weight based on the binder content of at least one silica gel suspension, 1% to 5% by weight based on the binder content of at least one plasticizer, 0.2% to 1% by weight based on the binder content of at least one stabilizer and 0% to 60% by volume/m.sup.3 of at least one lightweight aggregate.

The invention provides an aerogel-concrete mixture, a high-performance aerogel concrete obtained therefrom, and a method for production thereof. The problem addressed by the present application is that of providing pressure-resistant but not very thermally conductive concretes, precast concrete components, screeds, screeds for precast components, (glassfibre-) reinforced concrete, fire protection panels, construction elements for thermal partition and blocks. The aerogel-concrete mixture contains: 10% to 85% by volume/m.sup.3 of aerogel pellets having a grain size in the range from 0.01 to 4 mm, 100 to 900 kg/m.sup.3 of inorganic hydraulic binder, 10% to 40% by weight based on the binder content of at least one silica gel suspension, 1% to 5% by weight based on the binder content of at least one plasticizer, 0.2% to 1% by weight based on the binder content of at least one stabilizer and 0% to 60% by volume/m.sup.3 of at least one lightweight aggregate.

A dry papercrete mix is formed by preparing a wet pulp of fiber material such as newsprint and sharp sand by mixing sand, fiber material and water in a batch or continuous mixer, drying the pulp to a moisture content below that which will cause a reaction with Portland cement and adding additional sands and/or pumice and Portland cement. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can also be applied by pouring the dry papercrete mix into a desired volume such as a form in a dry state and injecting water into the dry papercrete mix until the mix is sufficiently wetted without a requirement for mixing in the manner common for concrete. Structural modules and a technique for joining them into a structure are particularly appropriate to the use of dry application papercrete.

A dry papercrete mix is formed by preparing a wet pulp of fiber material such as newsprint and sharp sand by mixing sand, fiber material and water in a batch or continuous mixer, drying the pulp to a moisture content below that which will cause a reaction with Portland cement and adding additional sands and/or pumice and Portland cement. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can also be applied by pouring the dry papercrete mix into a desired volume such as a form in a dry state and injecting water into the dry papercrete mix until the mix is sufficiently wetted without a requirement for mixing in the manner common for concrete. Structural modules and a technique for joining them into a structure are particularly appropriate to the use of dry application papercrete.

A gypsum board according to the invention comprises calcium sulphate dihydrate; Tartaric acid in an amount in the range of 0.01 to 0.1% w based on the weight of calcium sulphate hemihydrate; A fluidizer in an amount of 1.0 to 10.0 kg/m.sup.3; Starch in an amount of 3.0 to 12.0 kg/m.sup.3.

A gypsum board according to the invention comprises calcium sulphate dihydrate; Tartaric acid in an amount in the range of 0.01 to 0.1% w based on the weight of calcium sulphate hemihydrate; A fluidizer in an amount of 1.0 to 10.0 kg/m.sup.3; Starch in an amount of 3.0 to 12.0 kg/m.sup.3.

A photocatalytic composition comprising: (a) at least one aerial binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one pumice in the form of micronized powder; (f) at least one barite in the form of micronized powder. This composition can be used as water-based paint for preparing wall coatings having a very low thickness, in particular for interior applications, which guarantee a high photocatalytic effect and stable with time, even with relatively low quantities of photocatalyst, normally lower than 10% by weight. This coating also has marked inhibitory properties with respect to the growth of mold and bacteria on wall surfaces.

A photocatalytic composition comprising: (a) at least one aerial binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one pumice in the form of micronized powder; (f) at least one barite in the form of micronized powder. This composition can be used as water-based paint for preparing wall coatings having a very low thickness, in particular for interior applications, which guarantee a high photocatalytic effect and stable with time, even with relatively low quantities of photocatalyst, normally lower than 10% by weight. This coating also has marked inhibitory properties with respect to the growth of mold and bacteria on wall surfaces.

Aim of the present invention is to obtain cementitious products having smooth, planar surfaces and low thickness for applications having aesthetic purpose, of integrated architecture or as substrates, for example for a thin-film photovoltaic unit, with controlled curling and surface roughness, manufactured by mold casting of a fluid composition comprising: I. a hydraulic binder; II. one or more aggregates; III. an anti-shrinkage agent; IV. a superplasticizer agent; V. water, wherein the percentage by weight of said hydraulic binder in the composition is lower than that of said aggregates, and wherein said aggregates have a maximum diameter d.sub.max not greater than one third of the thickness of the product, the final product thus having an arithmetic mean surface roughness Ra not greater than 500 nm and curling not greater than 1500 micron.

Aim of the present invention is to obtain cementitious products having smooth, planar surfaces and low thickness for applications having aesthetic purpose, of integrated architecture or as substrates, for example for a thin-film photovoltaic unit, with controlled curling and surface roughness, manufactured by mold casting of a fluid composition comprising: I. a hydraulic binder; II. one or more aggregates; III. an anti-shrinkage agent; IV. a superplasticizer agent; V. water, wherein the percentage by weight of said hydraulic binder in the composition is lower than that of said aggregates, and wherein said aggregates have a maximum diameter d.sub.max not greater than one third of the thickness of the product, the final product thus having an arithmetic mean surface roughness Ra not greater than 500 nm and curling not greater than 1500 micron.