Provided is a resin that exhibits high resist performance because a poorly soluble component with respect to a resist solvent is reduced, and a production method for the resin. Disclosed is a photoresist resin containing an acrylic resin, in which when the photoresist resin is dissolved in propylene glycol monomethyl ether acetate in such a way that a resin solid content concentration is 5 wt %, a polystyrene equivalent turbidity measured using a method described in “Drinking Water Testing Methods” of Japan Water Works Association of 2003, Ministry of Health, Labor and Welfare Ordinance No. 261 of Japan is 30 or less.

Provided is a resin that exhibits high resist performance because a poorly soluble component with respect to a resist solvent is reduced, and a production method for the resin. Disclosed is a photoresist resin containing an acrylic resin, in which when the photoresist resin is dissolved in propylene glycol monomethyl ether acetate in such a way that a resin solid content concentration is 5 wt %, a polystyrene equivalent turbidity measured using a method described in “Drinking Water Testing Methods” of Japan Water Works Association of 2003, Ministry of Health, Labor and Welfare Ordinance No. 261 of Japan is 30 or less.

An object is to provide a viscosity index improver composition that is capable of properly regulating the HTHS viscosity in the effective temperature range of a lubricating oil composition to a lower range, and a lubricating oil composition containing the viscosity index improver composition, and the viscosity index improver composition contains a comb-shaped polymer (A) containing a structural unit derived from a macromonomer (α) and a structural unit derived from a particular monomer (A1), the macromonomer (α) having a (meth)acryloyl group at one end, and having a structural unit derived from a monomer (α1) selected from butadiene and hydrogenated butadiene.

An object is to provide a viscosity index improver composition that is capable of properly regulating the HTHS viscosity in the effective temperature range of a lubricating oil composition to a lower range, and a lubricating oil composition containing the viscosity index improver composition, and the viscosity index improver composition contains a comb-shaped polymer (A) containing a structural unit derived from a macromonomer (α) and a structural unit derived from a particular monomer (A1), the macromonomer (α) having a (meth)acryloyl group at one end, and having a structural unit derived from a monomer (α1) selected from butadiene and hydrogenated butadiene.

The present invention is related to water-swellable polymer particles which contain a hydrophilic base polymer (B) and a hydrophobic polymer (P). It is also related to a process for producing the water-swellable polymer particles, an article containing the water-swellable polymer particles and the use of the water-swellable polymer particles.

The present invention is related to water-swellable polymer particles which contain a hydrophilic base polymer (B) and a hydrophobic polymer (P). It is also related to a process for producing the water-swellable polymer particles, an article containing the water-swellable polymer particles and the use of the water-swellable polymer particles.

To provide a water/oil repellent article which presents little burden on the environment, while being excellent in water/oil repellency, washing durability of the water repellency and friction durability of the water repellency; a method for producing such a water/oil repellent article; and a water/oil repellent composition and a water/oil repellent kit to be used for producing such a water/oil repellent article. A water/oil repellent article that comprises a substrate and, as adhered to the surface of the substrate, a fluorinated polymer having structural units based on monomer (a) having a C.sub.1-6 perfluoroalkyl group, and a specific fluorinated ether compound; a method for producing the water/oil repellent article, which comprises letting the fluorinated polymer and fluorinated ether compound be adhered to the substrate; a water/oil repellent composition which comprises the fluorinated polymer and fluorinated ether compound; and a water/oil repellent kit which comprises a first container accommodating a first liquid containing the fluorinated polymer and a second container accommodating a second liquid containing the fluorinated ether compound.

To provide a water/oil repellent article which presents little burden on the environment, while being excellent in water/oil repellency, washing durability of the water repellency and friction durability of the water repellency; a method for producing such a water/oil repellent article; and a water/oil repellent composition and a water/oil repellent kit to be used for producing such a water/oil repellent article. A water/oil repellent article that comprises a substrate and, as adhered to the surface of the substrate, a fluorinated polymer having structural units based on monomer (a) having a C.sub.1-6 perfluoroalkyl group, and a specific fluorinated ether compound; a method for producing the water/oil repellent article, which comprises letting the fluorinated polymer and fluorinated ether compound be adhered to the substrate; a water/oil repellent composition which comprises the fluorinated polymer and fluorinated ether compound; and a water/oil repellent kit which comprises a first container accommodating a first liquid containing the fluorinated polymer and a second container accommodating a second liquid containing the fluorinated ether compound.

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##