Provided are a novel metallocene compound, a metallocene-supported catalyst, and a method of preparing a polyolefin using the same. The metallocene-supported catalyst according to the present disclosure exhibits a high polymerization activity even when the metallocene compound is supported on a support, thereby showing an excellent activity and preparing a polyolefin having a high molecular weight.

Provided are a novel metallocene compound, a metallocene-supported catalyst, and a method of preparing a polyolefin using the same. The metallocene-supported catalyst according to the present disclosure exhibits a high polymerization activity even when the metallocene compound is supported on a support, thereby showing an excellent activity and preparing a polyolefin having a high molecular weight.

Polymer particles excellent in uniform dispersibility and the use thereof are provided. The polymer particles contain a surfactant, and have a coefficient of variation in the volume-based particle diameter distribution in the range from not less than 13.0% to not more than 25.0%. When 15.0 g of water is added to 5.0 g of the polymer particles so as to disperse the polymer particles in the water by performing a dispersion treatment for 60 minutes using an ultrasonic cleaner, and furthermore when an obtained dispersion liquid is put into a centrifuge tube with an inside diameter of 24 mm so as to be centrifuged, by a centrifugal separator, under conditions that K factor is 6943 and a rotating time is 30 minutes to recover a supernatant, a concentration of non-volatile components in the obtained supernatant is less than 3.5 wt. %.

Polymer particles excellent in uniform dispersibility and the use thereof are provided. The polymer particles contain a surfactant, and have a coefficient of variation in the volume-based particle diameter distribution in the range from not less than 13.0% to not more than 25.0%. When 15.0 g of water is added to 5.0 g of the polymer particles so as to disperse the polymer particles in the water by performing a dispersion treatment for 60 minutes using an ultrasonic cleaner, and furthermore when an obtained dispersion liquid is put into a centrifuge tube with an inside diameter of 24 mm so as to be centrifuged, by a centrifugal separator, under conditions that K factor is 6943 and a rotating time is 30 minutes to recover a supernatant, a concentration of non-volatile components in the obtained supernatant is less than 3.5 wt. %.

A polymer containing a structural unit (I) represented by formula (1) is included in a radiation-sensitive composition. In formula (1), R.sup.2 is a single bond, a divalent hydrocarbon group, or the like. R.sup.3 is a divalent group represented by formula (2) or formula (3). R.sup.4 is a divalent organic group. Y.sup.? is a monovalent anion which can generate a sulfonic acid group, an imidic acid group, or a methide acid group through exposure to light. M.sup.a+ is an a-valent cation. a is 1 or 2.

##STR00001##

A star-shaped vinyl ether polymer, comprising a central core and an arm portion bonded to the central core, wherein: the arm portion comprises a repeating unit derived from a vinyl ether monomer; the star-shaped vinyl ether polymer comprises a structure represented by the following Formula (1):
YAr.sup.1NNAr.sup.2(1); wherein Y represents an ether bond, a thioether bond, a group NH, or a group OR.sup.1*, R.sup.1 represents an alkylene group, * represents a position bonded to Ar.sup.1 in Formula (I), Ar.sup.1 represents a substituted or unsubstituted divalent aromatic hydrocarbon group, and Ar.sup.2 represents a substituted or unsubstituted monovalent aromatic hydrocarbon group; and particularly the central core is formed by crosslinking of a polyfunctional coupling agent, wherein the polyfunctional coupling agent is a compound represented by the following Formula (3): ##STR00001## wherein R.sup.5 to R.sup.8 each independently represent a hydrogen atom or a methyl group, and R.sup.9 represents a divalent organic group.

Provided is a hollow resin particle which includes a shell portion and a hollow portion surrounded by the shell portion, can achieve a low dielectric constant and a low dielectric loss tangent, and can exhibit excellent heat resistance. In addition, there is provided a method for producing such a hollow resin particle. Furthermore, there is provided a use of such a hollow resin particle. The hollow resin particle according to an embodiment of the present invention is a hollow resin particle including a shell portion and a hollow portion surrounded by the shell portion, wherein the shell portion contains a polymer (P) having an ether structure represented by Formula (1) and a phosphate structure.

##STR00001##

A process for inhibiting the polymerization of cyclopentadiene compounds (B) by contacting the cyclopentadiene compound with a quinone methide compound (A) of structure (I), ##STR00001##
Compositions (AB) comprising (A) and (B) are also provided.

There is provided a novel, environmentally friendly primer for use in the pretreatment steps in electroless plating, which can be easily used in fewer steps with a lower cost. A primer for forming a metallic plating film on a substrate by electroless plating, the primer including: a hyperbranched polymer having an ammonium group at a molecular terminal and a weight-average molecular weight of 500 to 5,000,000; and a metal fine particle.

A resist composition having favorable sensitivity, roughness characteristics, and etching resistance; a resist pattern formation method; and a novel compound that is useful as a resin component for the resist composition. The resist composition generates an acid upon exposure to light and changes solubility in developing solutions by the action of the acid, and includes a polymer compound having a constituent unit derived from a compound represented by general formula (a0-m0), as a resin component that changes in solubility in developing solutions by the action of an acid. In general formula (a0-m0), W.sup.01 is a polymerizable-group-containing group; W.sup.02 is an aromatic hydrocarbon group; Ra.sup.01 is a specific acid-dissociable group; Ra.sup.02 is an iodine atom or a bromine atom; and n is an integer of 1 or greater

##STR00001##