A fluorine-containing resin composition of the present invention includes: a fluorine-containing resin; and a solvent in which the fluorine-containing resin is dissolved. The solvent is a perfluoroalkene. The fluorine-containing resin includes a fluorine-containing polymer including a structural unit (A) represented by the following formula (1).

##STR00001##

(In the formula (1), R.sub.ff.sup.1 to R.sub.ff.sup.4 each independently represent a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. R.sub.ff.sup.1 and R.sub.ff.sup.2 are optionally linked to form a ring.)

One aspect of the present invention is a fluorine resin refining method. The method includes refining a fluorine resin by bringing the fluorine resin into contact with a fluorinating agent at a temperature of (Tg.sub.135) C. or higher, where Tg.sub.1 is the glass transition temperature of the fluorine resin, and the fluorine resin includes a first fluorine-containing aliphatic ring structure in a molecular chain. The present invention makes it possible to produce a fluorine resin suitable for use in a plastic optical fiber. The first fluorine-containing aliphatic ring structure may have a dioxolane skeleton.

One aspect of the present invention is a fluorine resin refining method. The method includes refining a fluorine resin by bringing the fluorine resin into contact with a fluorinating agent at a temperature of (Tg.sub.135) C. or higher, where Tg.sub.1 is the glass transition temperature of the fluorine resin, and the fluorine resin includes a first fluorine-containing aliphatic ring structure in a molecular chain. The present invention makes it possible to produce a fluorine resin suitable for use in a plastic optical fiber. The first fluorine-containing aliphatic ring structure may have a dioxolane skeleton.

The present invention provides multifunctional monomers, including, but not limited to include multifunctional methylene malonate and methylene beta-ketoester monomers; methods for producing the same; and compositions and products formed therefrom. The multifunctional monomers of the invention may be produced by transesterification or by direct synthesis from monofunctional methylene malonate monomers or methylene beta-ketoester monomers. The present invention further compositions and products formed from methylene beta-ketoester monomers of the invention, including monomer-based products (e.g., inks, adhesives, coatings, sealants or reactive molding) and polymer-based products (e.g., fibers, films, sheets, medical polymers, composite polymers and surfactants).

A process for preparing isosorbide ethoxylate di(meth)acrylate by transesterifying alkyl (meth)acrylate with isosorbide ethoxylate, comprising the steps of: (i) ethoxylating isosorbide to give isosorbide ethoxylate, (ii) reacting alkyl (meth)acrylate with isosorbide ethoxylate in the presence of potassium phosphate as catalyst and a stabilizer and in the presence of an azeotroping agent which forms an azeotrope with the alcohol bound in the alkyl (meth)acrylate, (iii) continuously distilling off the azeotrope of azeotroping agent and alcohol, wherein steps (ii) and (iii) are conducted simultaneously until the isosorbide ethoxylate has been essentially fully converted, (iv) removing the catalyst from the product mixture comprising isosorbide ethoxylate di(meth)acrylate, (v) distilling unconverted alkyl (meth)acrylate and azeotroping agent out of the product mixture.

Monomers, polymers and copolymers are provided that incorporate at least one naturally occurring phenolic compound, such as a plant phenol.

Monomers, polymers and copolymers are provided that incorporate at least one naturally occurring phenolic compound, such as a plant phenol.

Resin particles including a unit of formula (1) and having a volume average particle diameter 5 to 2000 m, a method for producing, and a fluororesin comprising a unit of formula (1) and having a weight average molecular weight 510.sup.4 to 310.sup.5, and a yellow index of a heat-melted molded product (thickness 3 mm) after 24 h at 280 C. of 6 or less, ##STR00001## wherein Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 are independently a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, or a cyclic perfluoroalkyl group having 3 to 7 carbon atoms, and the perfluoroalkyl group may have an ethereal oxygen atom, and Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 may be linked to form a ring having 4 to 8 or carbon atoms.

Resin particles including a unit of formula (1) and having a volume average particle diameter 5 to 2000 m, a method for producing, and a fluororesin comprising a unit of formula (1) and having a weight average molecular weight 510.sup.4 to 310.sup.5, and a yellow index of a heat-melted molded product (thickness 3 mm) after 24 h at 280 C. of 6 or less, ##STR00001## wherein Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 are independently a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, or a cyclic perfluoroalkyl group having 3 to 7 carbon atoms, and the perfluoroalkyl group may have an ethereal oxygen atom, and Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 may be linked to form a ring having 4 to 8 or carbon atoms.

An onium salt monomer consists of a sulfonic acid anion containing a polymerizable group and being free of iodine and a triarylsulfonium cation containing iodine and fluorine. A resist composition comprising a polymer comprising repeat units derived from the monomer exhibits a high solvent solubility, high sensitivity and high contrast and forms a small-size pattern with satisfactory exposure latitude, edge roughness, dimension uniformity and depth of focus when processed by photolithography using high-energy radiation, as well as collapse resistance.