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.

The present invention relates to bi- and tricyclic compounds of the general formula (I) (I) wherein the dashed lines independently of each other represent a single or a double bond, X represents a group of the formulae X.sub.1 to X.sub.3 wherein the asterisk denotes the point of attachment to the rest of the molecule, R.sup.1a and R.sup.1b, independently of each other, are selected from hydrogen or methyl, or R.sup.1a together with R.sup.1b with R form a methylene or ethylene group, R.sup.2, R.sup.3a, R.sup.3b, R.sup.4, R.sup.5a and R.sup.5b, independently of each other, are selected from hydrogen or methyl, R.sup.6 is selected from hydrogen, methyl or ethyl, and R.sup.7 is methyl or ethyl, to a method of preparing said compounds, to the use of a bi- or tricyclic compounds or of mixtures of two or more bi- and tricyclic compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof as aroma chemicals; to the use of a bi- or tricyclic compound for modifying the scent character of a fragranced composition; to an aroma chemical composition containing a bi- or tricyclic compound or a mixture of two or more bi- and tricyclic compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof; and to a method of preparing a fragranced composition or for modifying the scent character of a fragranced composition, comprising incorporating a bi- or tricyclic compound or a mixture of two or more bi- and tricyclic compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof into said composition.

##STR00001##

Compounds useful for formulating inks, 3D printing resins, molding resins, coatings, sealants and adhesives which exhibit reduced shrinkage stress and high hardness and stiffness when cured are described which include a single free radical-polymerizable functional group, one or more urethane and/or ureido linkages and one or more cyclic structural elements per molecule.

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

Systems and methods for producing dicyclopentadiene from cyclopentadiene using reactive jet mixing are disclosed. A C.sub.5 hydrocarbon mixture that comprises cyclopentadiene (C.sub.5H.sub.6) is injected as a jet stream into C.sub.5 hydrocarbon liquid in a reactor tank. Under appropriate reaction conditions, cyclopentadiene is dimerized to form dicyclopentadiene.

A method of preparing 3(4),8(9)-bisformyltricyclo[5.2.1.0.sup.2,6]decane is provided. According to the present invention, 3(4),8(9)-bisformyltricyclo[5.2.1.0.sup.2,6]decane (TCDDA) may be prepared with a high conversion rate and purity without a separate catalyst recovery process.

A method for producing tricyclo[5.2.1.0.sup.2,6]decane-2-carboxylate according to the present invention is a method for producing tricyclo[5.2.1.0.sup.2,6]decane-2-carboxylate, containing reacting tricyclo[5.2.1.0.sup.2,6]deca-3-ene in a dilute solution containing the tricyclo[5.2.1.0.sup.2,6]deca-3-ene with carbon monoxide in the presence of an acid catalyst, followed by reaction with an alcohol, wherein the dilute solution contains 100 parts by mass or more of a tricyclo[5.2.1.0.sup.2,6]decane isomer mixture based on 100 parts by mass of the tricyclo[5.2.1.0.sup.2,6]deca-3-ene, the tricyclo[5.2.1.0.sup.2,6]decane isomer mixture contains endo-tricyclo[5.2.1.0.sup.2,6]decane (Endo form of TCD) and exo-tricyclo[5.2.1.0.sup.2,6]decane (Exo form of TCD), and a constituent ratio thereof (Endo form of TCD/Exo form of TCD) is greater than 1.0.

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 is a sulfonium salt represented by the following formula (1),

##STR00001##

wherein p represents an integer of 1 to 3; R.sup.11 represents a hydrocarbyl group having 1 to 20 carbon atoms; R.sup.f represents a fluorine atom or a fluorine-atom-containing C1 to C6 group selected from alkyl, alkoxy, and sulfide; q represents an integer of 1 to 4; R.sup.ALU represents an acid-labile group; r represents an integer of 1 to 4; R.sup.12 represents a hydrocarbyl group having 1 to 20 carbon atoms; s represents an integer of 0 to 4; t represents an integer of 0 to 2; R.sup.f and OR.sup.ALU are bonded to adjacent carbon atoms; and X.sup. represents a non-nucleophilic counterion having no polymerizable group. This provides a sulfonium salt used for a resist composition having excellent solvent solubility, high sensitivity and high contrast, and excellent lithographic performance such as exposure latitude and LWR; a resist composition containing the sulfonium salt as a photoacid generator; and a patterning process using the resist composition.

Dicyclopentadiene (DCPD) derivatives of following general formula (I); their preparation and use thereof, especially as monomers in polymerization reactions, such as olefin polymerization or ring-opening metathesis polymerization (ROMP). ##STR00001##