Addition curable composition containing specific silicone resins containing aliphatically unsaturated groups and an organic compound containing unsaturated groups such as acrylate or methacrylate groups are suitable when used with fine and coarse fillers to produce artificial stone with both high hardness and high flexural strength.

The present invention provides a binder for inorganic fibers characterized by containing (A) 100 parts by mass of a polyvinyl alcohol-based resin having a degree of polymerization of 100-3500, (B) 1-50 parts by mass of a metal salt, and (C) 3 parts by mass of an ammonia denatured product of a copolymerization product containing maleic anhydride. By using the binder for inorganic fibers according to the present invention, it is possible to produce an inorganic fiber mat having a high recovery rate comparable to that of phenol resins. In addition, the amount of volatile organic compounds released from such an inorganic fiber mat is extremely low.

The present invention provides a binder for inorganic fibers characterized by containing (A) 100 parts by mass of a polyvinyl alcohol-based resin having a degree of polymerization of 100-3500, (B) 1-50 parts by mass of a metal salt, and (C) 3 parts by mass of an ammonia denatured product of a copolymerization product containing maleic anhydride. By using the binder for inorganic fibers according to the present invention, it is possible to produce an inorganic fiber mat having a high recovery rate comparable to that of phenol resins. In addition, the amount of volatile organic compounds released from such an inorganic fiber mat is extremely low.

A porous body including an inorganic fiber and an organic binder, wherein the average fiber diameter of the inorganic fiber is 2.0 μm or less, the amount of the inorganic fiber is 90% by mass or more, the amount of the organic binder is 0.5% by mass or more and 10% by mass or less, the organic binder contains an elastomer, and the bulk density of the porous body is 30 kg/m.sup.3 or less.

A porous body including an inorganic fiber and an organic binder, wherein the average fiber diameter of the inorganic fiber is 2.0 μm or less, the amount of the inorganic fiber is 90% by mass or more, the amount of the organic binder is 0.5% by mass or more and 10% by mass or less, the organic binder contains an elastomer, and the bulk density of the porous body is 30 kg/m.sup.3 or less.

A barrier and method of manufacture thereof is provided. The barrier is suitable for enhancing the reaction to fire of structural elements such as construction boards.

A barrier and method of manufacture thereof is provided. The barrier is suitable for enhancing the reaction to fire of structural elements such as construction boards.

The present invention relates to inorganic fibres having a composition comprising: 61.0 to 70.8 wt% SiO.sub.2; 28.0 to 39.0 wt% CaO; 0.10 to 0.85 wt% MgO other components, if any, providing the balance up to 100 wt %,

The sum of SiO.sub.2 and CaO is greater than or equal to 98.8 wt % and the other components comprise less than 0.70 wt % Al.sub.2O.sub.3, if any.

The present invention relates to inorganic fibres having a composition comprising: 61.0 to 70.8 wt% SiO.sub.2; 28.0 to 39.0 wt% CaO; 0.10 to 0.85 wt% MgO other components, if any, providing the balance up to 100 wt %,

The sum of SiO.sub.2 and CaO is greater than or equal to 98.8 wt % and the other components comprise less than 0.70 wt % Al.sub.2O.sub.3, if any.

An acoustical geopolymer panel element includes a layer including a fibre component and a geopolymer binder made from a mixture including ground mineral wool, and an additional layer including mineral wool. The layer including a fibre component and a geopolymer binder has a density in the range of 20-400 kg/m.sup.3, a porosity in the range of 0.75-0.99 and a thickness in the range of 5-75 mm. The ground mineral wool may be ground glass or stone wool and the fibre component may be a wood fibre component, a polymer fibre component and/or a mineral wool component. Further, a geopolymer mixture is provided upon recycling mineral wool which is ground to powder and mixed with an alkali activator component. Additionally, a method for producing acoustical geopolymer panel elements includes grinding elements including mineral wool for provision of a powder component.