To provide a fluorinated elastic copolymer in which the contents of metal elements and chloride ions are low, and a method for producing a fluorinated elastic copolymer, whereby it is possible to obtain a fluorinated elastic copolymer in which the contents of metal elements and chloride ions are low. A fluorinated elastic copolymer in which the content of metal elements is at most 20.0 ppm by mass and the content of chloride ions is at most 1 ppm by mass; and a method for producing a fluorinated elastic copolymer, which comprises coagulating a fluorinated elastic copolymer in a latex containing the fluorinated elastic copolymer by using an acid containing no metal elements or no chloride ions, and washing the coagulated fluorinated elastic copolymer with a liquid medium having a content of metal elements of at most 2.0 ppm by mass and a content of chloride ions of at most 2 ppm by mass.

An ethylene-vinyl alcohol copolymer composition contains: (A) an ethylene-vinyl alcohol copolymer; (B) a long Periodic Table 4th-period d-block metal compound; and (C) an iron compound; wherein the iron compound (C) is present in an amount of 0.01 to 5 ppm on a metal basis based on the weight of the ethylene-vinyl alcohol copolymer composition. The ethylene-vinyl alcohol copolymer composition exhibits improved impact resistance and heat stability (color tone deterioration-suppressing effect and coloration-suppressing effect).

An ethylene-vinyl alcohol copolymer composition contains: (A) an ethylene-vinyl alcohol copolymer; (B) a long Periodic Table 4th-period d-block metal compound; and (C) an iron compound; wherein the iron compound (C) is present in an amount of 0.01 to 5 ppm on a metal basis based on the weight of the ethylene-vinyl alcohol copolymer composition. The ethylene-vinyl alcohol copolymer composition exhibits improved impact resistance and heat stability (color tone deterioration-suppressing effect and coloration-suppressing effect).

The present invention relates to [1] a colored fine particle dispersion containing colored fine particles and a neutralizing agent, in which the colored fine particles are produced by subjecting a monomer mixture containing an acid group-containing polymerizable monomer to emulsion polymerization in the presence of a pigment; the neutralizing agent contains a water-soluble amine compound; and the colored fine particle dispersion has a pH value of from 6 to 11, and [2] a process for producing a colored fine particle dispersion containing colored fine particles and a neutralizing agent, said process including the step 1 of subjecting a monomer mixture containing an acid group-containing polymerizable monomer to emulsion polymerization in the presence of a pigment to obtain a colored fine particle dispersion (p); and the step 2 of mixing the colored fine particle dispersion (p) and the neutralizing agent containing a water-soluble amine compound to obtain the colored fine particle dispersion having a pH value of from 6 to 11. The colored fine particle dispersion of the present invention is used in a water-based ink so that the resulting water-based ink is excellent in ejection stability upon evaporation of water from the ink system while maintaining excellent storage stability thereof, and it is possible to obtain printed materials that are excellent in alcohol resistance even when printed on a low-water absorbing printing medium.

The present invention relates to [1] a colored fine particle dispersion containing colored fine particles and a neutralizing agent, in which the colored fine particles are produced by subjecting a monomer mixture containing an acid group-containing polymerizable monomer to emulsion polymerization in the presence of a pigment; the neutralizing agent contains a water-soluble amine compound; and the colored fine particle dispersion has a pH value of from 6 to 11, and [2] a process for producing a colored fine particle dispersion containing colored fine particles and a neutralizing agent, said process including the step 1 of subjecting a monomer mixture containing an acid group-containing polymerizable monomer to emulsion polymerization in the presence of a pigment to obtain a colored fine particle dispersion (p); and the step 2 of mixing the colored fine particle dispersion (p) and the neutralizing agent containing a water-soluble amine compound to obtain the colored fine particle dispersion having a pH value of from 6 to 11. The colored fine particle dispersion of the present invention is used in a water-based ink so that the resulting water-based ink is excellent in ejection stability upon evaporation of water from the ink system while maintaining excellent storage stability thereof, and it is possible to obtain printed materials that are excellent in alcohol resistance even when printed on a low-water absorbing printing medium.

The present invention discloses a method for preparing a super absorbent resin including the following steps: 1) adding an inner-crosslinking agent, an active promoter, and an initiator to a solution of an unsaturated monomer in water, deoxygenating by bubbling nitrogen therethrough, and then undergoing free radical polymerization to obtain a gel; 2) reacting the gel with a neutralizing agent, extruding, and granulating to obtain a product; 3) drying, pulverizing, sieving, and fixing the particle size combination of the product to obtain powdered raw particles; 4) adding a surface crosslinking agent to the powdered raw particles and performing surface crosslinking by heating to obtained crosslinked particles; and 5) subjecting the crosslinked particles to anti-caking treatment to obtain a super absorbent resin.

The present invention relates to a method of preparing an aqueous dispersion of multistage polymer particles comprising contacting under emulsion polymerization conditions and in a staged fashion an aqueous dispersion of carboxylic acid functionalized core polymer particles with first monomers and second monomers. The core comprises structural units of a high T.sub.g hydrophobic monomer and/or the first monomers comprise a high T.sub.g hydrophobic monomer, and the second monomers comprise at least 80 percent styrene. The high T.sub.g hydrophobic monomer is cyclohexyl methacrylate, isobornyl methacrylate, 4-t-butyl methacrylate, t-butylstyrene, or n-butyl methacrylate, or a combination thereof. The multistage polymer particles are useful as opaque polymers, which are used in pigmented coating formulations to reduce the load of TiO.sub.2. The particles exhibit excellent collapse resistance and unusually low dry bulk density, and do not require acrylonitrile to achieve this desired combination of properties.

The present invention relates to a method of preparing an aqueous dispersion of multistage polymer particles comprising contacting under emulsion polymerization conditions and in a staged fashion an aqueous dispersion of carboxylic acid functionalized core polymer particles with first monomers and second monomers. The core comprises structural units of a high T.sub.g hydrophobic monomer and/or the first monomers comprise a high T.sub.g hydrophobic monomer, and the second monomers comprise at least 80 percent styrene. The high T.sub.g hydrophobic monomer is cyclohexyl methacrylate, isobornyl methacrylate, 4-t-butyl methacrylate, t-butylstyrene, or n-butyl methacrylate, or a combination thereof. The multistage polymer particles are useful as opaque polymers, which are used in pigmented coating formulations to reduce the load of TiO.sub.2. The particles exhibit excellent collapse resistance and unusually low dry bulk density, and do not require acrylonitrile to achieve this desired combination of properties.

Disclosed is a method for producing a polyolefin including: (1) a step (1) of polymerizing one or more olefins in solution polymerization or slurry polymerization in the presence of a polymerization catalyst to produce a polymer solution, (2) a step (2) of taking out the polymer solution obtained in the step (1), and adding a catalyst deactivator in the polymer solution to deactivate the polymerization catalyst, and (3) a step (3) of removing volatile components in vacuum from the polymer solution where the polymerization catalyst has been deactivated, and including, between the step (2) and the step (3), a step of adding an additive to the polymer solution when the water concentration in the polymer solution is 5 ppm by mass or less.

Disclosed is a method for producing a polyolefin including: (1) a step (1) of polymerizing one or more olefins in solution polymerization or slurry polymerization in the presence of a polymerization catalyst to produce a polymer solution, (2) a step (2) of taking out the polymer solution obtained in the step (1), and adding a catalyst deactivator in the polymer solution to deactivate the polymerization catalyst, and (3) a step (3) of removing volatile components in vacuum from the polymer solution where the polymerization catalyst has been deactivated, and including, between the step (2) and the step (3), a step of adding an additive to the polymer solution when the water concentration in the polymer solution is 5 ppm by mass or less.