This invention provides low dust low density gypsum wallboard products having high total core void volumes, corresponding to low densities in the range of about 10 to 30 pcf. The wallboards have a set gypsum core formed between two substantially parallel cover sheets, the set gypsum core preferably having a total void volume from about 80% to about 92%, and made from a slurry including stucco, pregelatinized starch, and a naphthalenesulfonate dispersant. The combination of the pregelatinized starch and the naphthalenesulfonate dispersant also provides a glue-like effect in binding the set gypsum crystals together. The wallboard formulation, along with small air bubble voids (and water voids) provides dust control during cutting, sawing, routing, snapping, nailing or screwing down, or drilling of the gypsum-containing products. This invention also provides a method of making the low dust low density gypsum products including the introduction of soap foam in an amount sufficient to form a total void volume, including air voids, preferably from about 80% to about 92% in the set gypsum core, corresponding to a set gypsum core density from about 10 pcf to about 30 pcf. The wallboards produced by the method generate significantly less dust during working.

This invention provides low dust low density gypsum wallboard products having high total core void volumes, corresponding to low densities in the range of about 10 to 30 pcf. The wallboards have a set gypsum core formed between two substantially parallel cover sheets, the set gypsum core preferably having a total void volume from about 80% to about 92%, and made from a slurry including stucco, pregelatinized starch, and a naphthalenesulfonate dispersant. The combination of the pregelatinized starch and the naphthalenesulfonate dispersant also provides a glue-like effect in binding the set gypsum crystals together. The wallboard formulation, along with small air bubble voids (and water voids) provides dust control during cutting, sawing, routing, snapping, nailing or screwing down, or drilling of the gypsum-containing products. This invention also provides a method of making the low dust low density gypsum products including the introduction of soap foam in an amount sufficient to form a total void volume, including air voids, preferably from about 80% to about 92% in the set gypsum core, corresponding to a set gypsum core density from about 10 pcf to about 30 pcf. The wallboards produced by the method generate significantly less dust during working.

The present invention relates to a light-transmitting ceramic sintered body which contains air voids having pore diameters of 1 μm or more but less than 5 μm at a density within the range of from 10 voids/mm.sup.3 to 4,000 voids/mm.sup.3 (inclusive), while having a closed porosity of from 0.01% by volume to 1.05% by volume (inclusive). With respect to this light-transmitting ceramic sintered body, a test piece having a thickness of 1.90 mm has an average transmittance of 70% or more in the visible spectrum wavelength range of 500-900 nm, and the test piece having a thickness of 1.90 mm has a sharpness of 60% or more at a comb width of 0.5 mm.

The present invention relates to a light-transmitting ceramic sintered body which contains air voids having pore diameters of 1 μm or more but less than 5 μm at a density within the range of from 10 voids/mm.sup.3 to 4,000 voids/mm.sup.3 (inclusive), while having a closed porosity of from 0.01% by volume to 1.05% by volume (inclusive). With respect to this light-transmitting ceramic sintered body, a test piece having a thickness of 1.90 mm has an average transmittance of 70% or more in the visible spectrum wavelength range of 500-900 nm, and the test piece having a thickness of 1.90 mm has a sharpness of 60% or more at a comb width of 0.5 mm.

A lithium composite oxide sintered body plate includes a porous structure in which a plurality of primary particles of a lithium composite oxide having a layered rock-salt structure are bonded is included, in which a porosity is 15 to 50%, a ratio of the primary particles whose average inclination angle being an average value of angles between a (003) plane of the plurality of primary particles and a plate surface of the sintered body plate is more than 0° and 30° or less is 60% or more, one or more additive elements selected from Nb, Ti, W are contained, and an addition amount of the one or more additive elements to an entire of the sintered body plate is 0.01 wt % or more and 2.0 wt % or less.

A lithium composite oxide sintered body plate includes a porous structure in which a plurality of primary particles of a lithium composite oxide having a layered rock-salt structure are bonded is included, in which a porosity is 15 to 50%, a ratio of the primary particles whose average inclination angle being an average value of angles between a (003) plane of the plurality of primary particles and a plate surface of the sintered body plate is more than 0° and 30° or less is 60% or more, one or more additive elements selected from Nb, Ti, W are contained, and an addition amount of the one or more additive elements to an entire of the sintered body plate is 0.01 wt % or more and 2.0 wt % or less.

Provided are a method of manufacturing a ceramic article including a porous portion in which improvement in mechanical strength of a modeled article is achieved while high modeling accuracy is obtained, and a ceramic article. The method of manufacturing a ceramic article includes the steps of: (i) irradiating powder of a metal oxide containing aluminum oxide as a main component with an energy beam based on modeling data to melt and solidify or sinter the powder, to thereby form a modeled article including a porous portion; (ii) causing the modeled article formed in the step (i) to absorb a liquid containing a zirconium component; and (iii) heating the modeled article that has absorbed the liquid containing the zirconium component, wherein, in the absorbing step, the liquid is absorbed so that a ratio of the zirconium component in a metal component contained in the porous portion becomes 0.3 to 2.0 mol %.

A cellular material includes a continuous solid phase including an ordered ceramic material, the solid phase having a solid core including the ordered ceramic material. A composition for forming a cellular material includes: a first UV curable pre-ceramic monomer; a second UV curable pre-ceramic monomer; and a photoinitiator. A method of forming at least one ceramic waveguide includes: securing a volume of a composition including a UV curable pre-ceramic monomer; exposing the composition to a light source to form at least one polymer waveguide including a pre-ceramic material; and converting the pre-ceramic material of the polymer waveguide to a ceramic material to form a ceramic waveguide.

A cellular material includes a continuous solid phase including an ordered ceramic material, the solid phase having a solid core including the ordered ceramic material. A composition for forming a cellular material includes: a first UV curable pre-ceramic monomer; a second UV curable pre-ceramic monomer; and a photoinitiator. A method of forming at least one ceramic waveguide includes: securing a volume of a composition including a UV curable pre-ceramic monomer; exposing the composition to a light source to form at least one polymer waveguide including a pre-ceramic material; and converting the pre-ceramic material of the polymer waveguide to a ceramic material to form a ceramic waveguide.

The present invention is directed to a porous pre-densified CeO.sub.2-stabilized ZrO.sub.2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50% as well as to a densified CeO.sub.2-stabilized ZrO.sub.2 ceramic having a density of 97.0 to 100.0%, relative to the theoretical density of zirconia, and wherein the grains of the ceramic have an average grain size of 50 to 1000 nm, methods for the preparation of the pre-densified and densified ceramics and their use for the manufacture of dental restorations.