The present invention relates to novel compounds and their use as fragrance materials.

A resist composition comprising a base polymer and a sulfonium salt of iodized benzoic acid offers a high sensitivity and minimal LWR independent of whether it is of positive or negative tone.

The present invention aims to provide a means by which a cured product to be obtained has a low dielectric loss tangent and higher heat resistance. Specifically, provided are an active ester compound represented by chemical formula (1):

##STR00001## (where in chemical formula (1), Ar.sup.1 is a substituted or unsubstituted first aromatic ring group, and each Ar.sup.2 is independently a substituted or unsubstituted second aromatic ring group, in which at least one of Ar.sup.1 and Ar.sup.2 has an unsaturated bond-containing substituent, and n is an integer of 2 or 3), a curable composition containing the active ester compound, and a cured product thereof.

Methods and systems for recovering dicyclopentadiene from pygas are provided. Methods can include heating pygas to generated heated pygas, recovering a C.sub.5 fraction from the heated pygas, and dimerizing cyclopentadiene from the C.sub.5 fraction to form dicyclopentadiene. Methods can further include recovering the C.sub.5 fraction from the pygas in a depentanizer column. Other methods can include heating pygas including dicyclopentadiene to form cyclopentadiene and hydrogenating cyclopentadiene in the pygas to form cyclopentane.

A dynamic process for purifying dicyclopentadiene from a mixed liquid hydrocarbon stream comprising dicyclopentadiene and one or more of a C.sub.5 paraffin, a C.sub.5 olefin, co-dimers, cyclopentadiene, benzene, vinyl norbornene, bicyclononadiene, propenyl norbornene, isopropenyl norbornene, methylbicyclononadiene, methyldicyclopentadiene, and various minor organic impurities is introduced, wherein the dicyclopentadiene is separated from the mixed liquid hydrocarbon stream by melt crystallizing sweating and collecting dicyclopentadiene.

The invention relates to an extraction process for the recovery of high-boiling aldehyde products and catalysts from a hydroformylation product solution.

Provided are a tricyclodecane dimethanol composition which may be usefully applied to the preparation of a high heat resistant polyester by reducing the content of impurities, and a preparation method thereof.

A system and a process for dimerizing cyclopentadiene (CPD) including producing a C.sub.6+C.sub.7 rich bottoms stream and a C.sub.5 rich side draw from a debutanizer, where the C.sub.5 rich side draw and at least a portion of the C.sub.6+C.sub.7 rich bottoms stream are directed to a dimerizer where the CPD is thermally dimerized to dicyclopentadiene (DCPD). DCPD is more stable than CPD and thus safer to handle.

A novel compound is provided. The novel compound is represented by General Formula (G1). ##STR00001##
In General Formula (G1), A represents a substituted or unsubstituted condensed aromatic ring having 10 to 30 carbon atoms or a substituted or unsubstituted condensed heteroaromatic ring having 10 to 30 carbon atoms, and R.sup.1 represents a substituted or unsubstituted aryl group having 6 to 25 carbon atoms. Each of Y.sup.1 and Y.sup.2 independently represents a cycloalkyl group having a bridge structure and having 7 to 10 carbon atoms.

The present invention relates to a process for the preparation of polycyclic aliphatic dialdehydes by hydroformylation of polycyclic aliphatic diolefins in the presence of synthesis gas over an organophosphorus ligand modified metal catalyst system having a transition metal of the 8.sup.th-10.sup.th subgroup, wherein the hydroformylation is carried out by means of a water-soluble diphosphine or triarylphosphine complex catalyst at a pressure of greater than or equal to 0.5 MPa and less than or equal to 10 MPa and at a temperature of greater than or equal to 70 C. and less than or equal to 150 C. in a homogeneous liquid reaction phase, the homogeneous liquid phase comprising at least one non-aqueous solvent, diolefin and/or mono- and/or dialdehydes thereof as reaction products and an aqueous catalyst solution, the proportions of these components in the solution being controlled so as to obtain a single-phase solution under the reaction conditions.