Abstract: A polyurethane resin composition for optical applications can contain, as essential components, a polyisocyanate and a polyester-ether polyol obtained by polycondensation of a glycol component containing an alkylene oxide adduct of a bisphenol and an aromatic carboxylic acid component and particularly preferably having a glass transition temperature of 50° C. or lower. An optical material using the composition is also provided for.

Abstract: A polyurethane resin composition for optical applications can contain, as essential components, a polyisocyanate and a polyester-ether polyol obtained by polycondensation of a glycol component containing an alkylene oxide adduct of a bisphenol and an aromatic carboxylic acid component and particularly preferably having a glass transition temperature of 50° C. or lower. An optical material using the composition is also provided for.

Abstract: The present invention relates to a solid acid catalyst for the production of polyester which enables the production of a metal-free polyester resin containing no residual catalyst, exhibits favorable utility efficiency in the production, exhibits extremely high selectivity for the polyesterification reaction with the amount of by-products being below the limit of detection, and is able to be isolated, recovered and reused. In other words, the present invention relates to a solid acid catalyst for the production of polyester, obtained by supporting a metal oxide (B) on a support (A) formed from a metal oxide, wherein said support (A) formed from a metal oxide is a zirconia, said metal oxide (B) is a molybdenum oxide, and a Hammett acidity function (H0) for said catalyst is within a range from ?3 to ?9, and also relates to a process for producing the solid acid catalyst and a process for producing a polyester that uses the catalyst.

Abstract: The present invention relates to a solid acid catalyst for the production of polyester which enables the production of a metal-free polyester resin containing no residual catalyst, exhibits favorable utility efficiency in the production, exhibits extremely high selectivity for the polyesterification reaction with the amount of by-products being below the limit of detection, and is able to be isolated, recovered and reused. In other words, the present invention relates to a solid acid catalyst for the production of polyester, obtained by supporting a metal oxide (B) on a support (A) formed from a metal oxide, wherein said support (A) formed from a metal oxide is a zirconia, said metal oxide (B) is a molybdenum oxide, and a Hammett acidity function (H0) for said catalyst is within a range from ?3 to ?9, and also relates to a process for producing the solid acid catalyst and a process for producing a polyester that uses the catalyst.

Abstract: A method for removing an acidic component such as sulfite gas (SO2) contained in an exhaust gas comprising by using a system comprising (a) a gas-liquid contact apparatus composed of an absorption column provided internally with at least one perforated plate at the top, bottom, or both top and bottom of the absorption column packed with at least one type of fillers, (b) an apparatus for introducing raw seawater to the absorption column, (c) an apparatus for oxidizing the seawater after gas-liquid contact, and (d) an apparatus for mixing raw seawater with the contact seawater after oxidation, whereby the exhaust gas containing an acidic component is brought into gas-liquid contact with the seawater.

Abstract: The panel material of the present invention comprises (A) two sheets of FRP molded board as upper and lower surface materials, and, as a core material, (B) a high density, rigid polyurethane foam layer which has been obtained by injecting a rigid polyurethane foam starting material between these two sheets of FRP molded board and allowing this starting material to foam, and which has a closed cell structure and a density of 0.2.about.0.5 g/cm.sup.3. In addition, the manufacturing method of the panel material of the present invention includes a process for obtaining an integrally molded sandwich panel by injecting a rigid polyurethane foam starting material into a space between two sheets of FRP molded board which have been set in a mold, and allowing it to foam; and a process in which panel material is made by cutting this sandwich panel to a desired size.