An actinic ray-sensitive or radiation-sensitive resin composition includes a resin whose solubility in an aqueous alkali solution increases by the action of an acid, a compound that generates an acid upon irradiation with actinic rays or radiation, an ester compound, and a fluorine-containing polymer, in which the ester compound has alkali decomposability and has a molecular weight of 50 or more and less than 1,500.

Copolymers of one or more halogenated olefins and one or more halogenated co-monomers selected from the group consisting of halogenated alkenyl ethers, halogenated alkenyl esters, and halogenated (meth)acrylates are useful in various end-use applications wherein the presence of halogen (e.g., fluorine) in the copolymer imparts one or more desirable properties, as compared to analogous copolymers not containing halogen.

Copolymers of one or more halogenated olefins and one or more halogenated co-monomers selected from the group consisting of halogenated alkenyl ethers, halogenated alkenyl esters, and halogenated (meth)acrylates are useful in various end-use applications wherein the presence of halogen (e.g., fluorine) in the copolymer imparts one or more desirable properties, as compared to analogous copolymers not containing halogen.

A fluorine-containing polymer includes a repeating unit represented by General Formula (I). In General Formula (I), L.sub.1 represents a single bond or a divalent linking group, R.sub.1 represents a hydrogen atom, a fluorine atom, a chlorine atom, or an alkyl group having 1 to 20 carbon atoms, and R.sub.2 represents a group including a fluorine atom

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A fluorine-containing polymer includes a repeating unit represented by General Formula (I). In General Formula (I), L.sub.1 represents a single bond or a divalent linking group, R.sub.1 represents a hydrogen atom, a fluorine atom, a chlorine atom, or an alkyl group having 1 to 20 carbon atoms, and R.sub.2 represents a group including a fluorine atom

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A method for producing a hollow fine particulate containing a fluorine-containing resin and having a large average particle size. The method includes dispersing a solution containing a fluorine-containing monomer, a phase separation promoter, and a non-polymerizable solvent into water to provide a dispersion, and polymerizing the fluorine-containing monomer to provide a hollow fine particulate containing a fluorine-containing resin.

The invention provides novel bromine-containing polymers which have excellent heat resistance and are capable of imparting flame retardance or novel flame-retardant, bromine-containing polymers which have excellent heat resistance and optical characteristics, and methods for producing such polymers. The invention relates to a polymer which includes structural units of the following general formula (1):

##STR00001##

wherein R.sub.1s, R.sub.2s, m, p and the asterisks are as defined in the specification and the claims, and
to a method for producing such polymers.

The invention provides novel bromine-containing polymers which have excellent heat resistance and are capable of imparting flame retardance or novel flame-retardant, bromine-containing polymers which have excellent heat resistance and optical characteristics, and methods for producing such polymers. The invention relates to a polymer which includes structural units of the following general formula (1):

##STR00001##

wherein R.sub.1s, R.sub.2s, m, p and the asterisks are as defined in the specification and the claims, and
to a method for producing such polymers.

Provided is an optical fiber which has exceptional heat resistance and is highly safe. This optical fiber has a core, and a sheath of a least one layer around the outside circumference of the core, the sheath including a polymer that contains a repeating unit (A) derived from a fluoroalkyl (meth)acrylate having a specific structure.

Provided is an optical fiber which has exceptional heat resistance and is highly safe. This optical fiber has a core, and a sheath of a least one layer around the outside circumference of the core, the sheath including a polymer that contains a repeating unit (A) derived from a fluoroalkyl (meth)acrylate having a specific structure.