Abstract: A method for treating an aqueous fluid resulting from a fluorine-containing polymer production step, the method comprising: separating the aqueous fluid into a solid component and a filtrate using a filter aid.

Abstract: There is provided a method for producing a C2-C20 fluorine-containing organic acid with reduced fluorine-free organic compound. A method for producing a C2-C20 fluorine-containing organic acid, the method including contacting a mixture containing a C2-C20 fluorine-containing organic acid and a fluorine-free organic compound with a concentrated sulfuric acid and then separating a C2-C20 fluorine-containing organic acid phase from a concentrated sulfuric acid phase. The contacting is conducted such that an amount of water present in the concentrated sulfuric acid phase is 10% by mass or less, and the C2-C20 fluorine-containing organic acid is obtained in the form of the C2-C20 fluorinated organic acid phase having a reduced content ratio of the fluorine-free organic compound compared with said mixture.

Abstract: A method for treating an aqueous fluid resulting from a fluorine-containing polymer production step, the method comprising: separating the aqueous fluid into a solid component and a filtrate using a filter aid.

Abstract: There is provided a method for producing a C2-C20 fluorine-containing organic acid with reduced fluorine-free organic compound. A method for producing a C2-C20 fluorine-containing organic acid, wherein the method comprises contacting a mixture containing a C2-C20 fluorine-containing organic acid and a fluorine-free organic compound with a concentrated sulfuric acid and then separating a C2-C20 fluorine-containing organic acid phase from a concentrated sulfuric acid phase, wherein the contacting is conducted such that an amount of water present in the concentrated sulfuric acid phase is 10% by mass or less, and the C2-C20 fluorine-containing organic acid is obtained in the form of the C2-C20 fluorinated organic acid phase having a reduced content ratio of the fluorine-free organic compound compared with said mixture.

Abstract: A treatment method of at least partially removing impurities from a composition containing a fluorine-containing organic acid having the carbon number of 2 to 7 and impurities, the method including a flocculant mixing step of mixing the composition and a flocculant; and a separating step of separating a mixed phase obtained at the mixing step into a solid phase and a liquid phase.

Abstract: A treatment method of at least partially removing impurities from a composition containing a fluorine-containing organic acid having the carbon number of 2 to 7 and impurities, the method including a flocculant mixing step of mixing the composition and a flocculant; and a separating step of separating a mixed phase obtained at the mixing step into a solid phase and a liquid phase.

Abstract: There is provided a curable surface modifier comprising a resin which is soluble in a general purpose solvent and comprises a fluorine-containing ethylenic polymer containing, in at least a part of its side chain, a moiety A having a long polyfluoropolyether chain and/or a moiety B having a self-crosslinkable functional group, in which the resin contains both of the moieties A and B. The curable surface modifier improves properties of surfaces of various coating films, especially antireflection films, such as surface sliding property (decrease in a friction coefficient), surface hardness, abrasion resistance, chemical resistance and stain removability by wiping, thus being capable of imparting modified properties to the surfaces of original coating films.

Abstract: A curable fluorine-containing polymer having a number average molecular weight of from 500 to 1,000,000 and is represented by the formula (1): -(A)-(M)- in which the structural unit M is a structural unit derived from a fluorine-containing ethylenic monomer and represented by the formula (M): [—(CX1X2—CX3)—]—(CX4CX5)a—(C?O)b(O)c—Rf, wherein X1 and X2 are the same or different and each is H or F; X3 is H, F, CH3 or CF3; X4 and X5 are the same or different and each is H, F or CF3; Rf is an organic group as defined herein; a is 0 or an integer of from 1 to 3; b and c are the same or different and each is 0 or 1, and the structural unit A is derived from a monomer copolymerizable with the fluorine-containing ethylenic monomer from which M is derived.

Abstract: There are provided a curable fluorine-containing polymer which can realize a high hardness by photo-curing while maintaining a low refractive index, an antireflection film possessing improved scratch resistance and abrasion resistance while maintaining a reflection reducing effect, and an antireflection-treated article provided with such an antireflection film.

Abstract: There is provided a fluorine-containing resin composition which is used for nonlinear optical material and comprises (I) a fluorine-containing prepolymer and (II) an organic compound exhibiting a second- or higher-order nonlinear optical effect, in which the fluorine-containing prepolymer (I): (1) is a non-crystalline polymer having a fluorine content of not less than 25% and (2) has a carbon-carbon double bond in a polymer side chain or at an end of a polymer trunk chain and also there is provided a nonlinear optical waveguide device produced from the fluorine-containing resin composition. A suitable nonlinear optical material having a stable structure with a nonlinear substance is produced, and an excellent nonlinear optical waveguide device is produced by relatively simple steps while maintaining transparency in a near infrared region.

Abstract: There is formed a laminated resist which exhibits sufficient reflection reducing effect in a photolithography process using light of vacuum ultraviolet region and also has sufficient developing characteristics in a developing process. The method of forming the laminated photoresist comprises (I) a step for forming the photoresist layer (L1) on a substrate and (II) a step for forming the antireflection layer (L2) on the photoresist layer (L1) by applying the coating composition containing the fluorine-containing polymer (A) having hydrophilic group Y. The fluorine-containing polymer (A) contains a structural unit derived from a fluorine-containing ethylenic monomer having hydrophilic group Y and is characterized in that (i) the hydrophilic group Y contains an acidic OH group having a pKa value of not more than 11, (ii) a fluorine content is not less than 50% by mass, and (iii) the number of moles of the hydrophilic group Y in 100 g of the fluorine-containing polymer (A) is not less than 0.14.

Abstract: There can be obtained a suitable optical material which has a stable structure with a rare earth metal ion while maintaining transparency in a region of from visible light to near infrared light. The optical material is obtained by curing a fluorine-containing resin composition comprising (I) a fluorine-containing prepolymer and (II) a compound containing a rare earth metal ion and/or a rare earth metal element, wherein the fluorine-containing prepolymer (I) is a curable fluorine-containing polymer which: (1) is a non-crystalline polymer having a fluorine content of not less than 25% by weight and (2) has a cure site in a side chain of the polymer and/or at an end of a trunk chain of the polymer.

Abstract: There is provided a material which can give a high elasticity and heat resistance to an optical waveguide member by photo-curing while maintaining transparency in a near infrared region and further makes it possible to use a film forming process by a spin coating method and a process for producing a waveguide by photolithograph, to obtain a waveguide having a large area and to produce an optical waveguide having reduced water absorption, and further there can be provided an optical waveguide member and an optical waveguide device. Namely, there are provided a fluorine-containing optical waveguide material comprising a curable fluorine-containing prepolymer (I) which is a non-crystalline polymer having a fluorine content of not less than 25% by weight and has a carbon-carbon double bond in a polymer side chain and/or at an end of a polymer trunk chain, an optical waveguide member which is a cured article of the optical waveguide material and an optical waveguide device comprising the optical waveguide member.

Abstract: There is provided a curable surface modifier comprising a resin which is soluble in a general purpose solvent and comprises a fluorine-containing ethylenic polymer containing, in at least a part of its side chain, a moiety A having a long polyfluoropolyether chain and/or a moiety B having a self-crosslinkable functional group, in which the resin contains both of the moieties A and B. The curable surface modifier improves properties of surfaces of various coating films, especially antireflection films, such as surface sliding property (decrease in a friction coefficient), surface hardness, abrasion resistance, chemical resistance and stain removability by wiping, thus being capable of imparting modified properties to the surfaces of original coating films.

Abstract: There are provided a curable fluorine-containing polymer which can realize a high hardness by photo-curing while maintaining a low refractive index, an antireflection film possessing improved scratch resistance and abrasion resistance while maintaining a reflection reducing effect, and an antireflection-treated article provided with such an antireflection film.

Abstract: There are provided various optical materials which contain a curable fluorine-containing polymer (I) having a number average molecular weight of from 500 to 1,000,000 and represented by the formula (1): MA??(1) in which the structural unit M is a structural unit derived from a fluorine-containing organic group having crosslinkable cyclic ether structures in its side chain, the structural unit A is a structural unit derived from a monomer copolymerizable with the fluorine-containing ethylenic monomer for the structural unit represented by the formula (M), and the structural unit M and the structural unit A are contained in amounts of from 0.1 to 100% by mole and from 0 to 99.9% by mole, respectively, and further contain a photoacid generator (II).

Abstract: There is provided a material which can give a high elasticity and heat resistance to an optical waveguide member by photo-curing while maintaining transparency in a near infrared region and further makes it possible to use a film forming process by a spin coating method and a process for producing a waveguide by photolithograph, to obtain a waveguide having a large area and to produce an optical waveguide having reduced water absorption, and further there can be provided an optical waveguide member and an optical waveguide device. Namely, there are provided a fluorine-containing optical waveguide material comprising a curable fluorine-containing prepolymer (I) which is a non-crystalline polymer having a fluorine content of not less than 25% by weight and has a carbon-carbon double bond in a polymer side chain and/or at an end of a polymer trunk chain, an optical waveguide member which is a cured article of the optical waveguide material and an optical waveguide device comprising the optical waveguide member.

Abstract: There is provided a material which can give a high elasticity and heat resistance to an optical waveguide member by photo-curing while maintaining transparency in a near infrared region and further makes it possible to use a film forming process by a spin coating method and a process for producing a waveguide by photolithograph, to obtain a waveguide having a large area and to produce an optical waveguide having reduced water absorption, and further there can be provided an optical waveguide member and an optical waveguide device. Namely, there are provided a fluorine-containing optical waveguide material comprising a curable fluorine-containing prepolymer (I) which is a non-crystalline polymer having a fluorine content of not less than 25% by weight and has a carbon-carbon double bond in a polymer side chain and/or at an end of a polymer trunk chain, an optical waveguide member which is a cured article of the optical waveguide material and an optical waveguide device comprising the optical waveguide member.

Abstract: There is provided a fluorine-containing resin composition which is used for nonlinear optical material and comprises (I) a fluorine-containing prepolymer and (II) an organic compound exhibiting a second- or higher-order nonlinear optical effect, in which the fluorine-containing prepolymer (I): (1) is a non-crystalline polymer having a fluorine content of not less than 25% and (2) has a carbon-carbon double bond in a polymer side chain or at an end of a polymer trunk chain and also there is provided a nonlinear optical waveguide device produced from the fluorine-containing resin composition. A suitable nonlinear optical material having a stable structure with a nonlinear substance is produced, and an excellent nonlinear optical waveguide device is produced by relatively simple steps while maintaining transparency in a near infrared region.

Abstract: There is provided a material which can give a high elasticity and heat resistance to an optical waveguide member by photo-curing while maintaining transparency in a near infrared region and further makes it possible to use a film forming process by a spin coating method and a process for producing a waveguide by photolithograph, to obtain a waveguide having a large area and to produce an optical waveguide having reduced water absorption, and further there can be provided an optical waveguide member and an optical waveguide device. Namely, there are provided a fluorine-containing optical waveguide material comprising a curable fluorine-containing prepolymer (I) which is a non-crystalline polymer having a fluorine content of not less than 25% by weight and has a carbon-carbon double bond in a polymer side chain and/or at an end of a polymer trunk chain, an optical waveguide member which is a cured article of the optical waveguide material and an optical waveguide device comprising the optical waveguide member.