An object of the present invention is to provide a binder which exhibits excellent dispersibility of a conductive assistant; a slurry composition and an electrode, each of which uses this binder; and an electricity storage device which is provided with this electrode. The present invention relates to a binder for an electricity storage device, in which a loss tangent tan δ in a linear region of an aqueous dispersion liquid of 0.5% by mass of the binder and 4.6% by mass of a conductive assistant satisfies tan δ>1 in a strain dispersion measurement under measurement conditions of a measurement temperature of 25° C. and a frequency of 1 Hz, and the conductive assistant is an acetylene black having an average particle diameter of 30 nm or more and 40 nm or less and a specific surface area of 65 m.sup.2/g or more and 70 m.sup.2/g or less; a slurry composition and an electrode, each of which uses this binder; an electricity storage device which is provided with this electrode; and the like.

An object of the present invention is to provide a binder which exhibits excellent dispersibility of a conductive assistant; a slurry composition and an electrode, each of which uses this binder; and an electricity storage device which is provided with this electrode. The present invention relates to a binder for an electricity storage device, in which a loss tangent tan δ in a linear region of an aqueous dispersion liquid of 0.5% by mass of the binder and 4.6% by mass of a conductive assistant satisfies tan δ>1 in a strain dispersion measurement under measurement conditions of a measurement temperature of 25° C. and a frequency of 1 Hz, and the conductive assistant is an acetylene black having an average particle diameter of 30 nm or more and 40 nm or less and a specific surface area of 65 m.sup.2/g or more and 70 m.sup.2/g or less; a slurry composition and an electrode, each of which uses this binder; an electricity storage device which is provided with this electrode; and the like.

A method of forming a three-dimensional object comprises the steps of forming a layer of a particulate composition, selectively depositing a liquid composition onto the layer of the particulate composition in accordance with computer data corresponding to the shape of at least a portion of a three-dimensional object, and repeating the steps a plurality of times to form a three-dimensional object. The particulate composition comprises a plurality of first particles that comprise a resin component comprising a first resin, the first resin comprising a first resin polymerizable group. Either or both of the particulate composition and the liquid composition comprise an initiator capable of initiating polymerization of at least the first resin. At least the first resin undergoes melting and polymerization in a plurality of the locations where the liquid composition has been selectively deposited.

A method of forming a three-dimensional object comprises the steps of forming a layer of a particulate composition, selectively depositing a liquid composition onto the layer of the particulate composition in accordance with computer data corresponding to the shape of at least a portion of a three-dimensional object, and repeating the steps a plurality of times to form a three-dimensional object. The particulate composition comprises a plurality of first particles that comprise a resin component comprising a first resin, the first resin comprising a first resin polymerizable group. Either or both of the particulate composition and the liquid composition comprise an initiator capable of initiating polymerization of at least the first resin. At least the first resin undergoes melting and polymerization in a plurality of the locations where the liquid composition has been selectively deposited.

Provided is a technique for preparing an excellent viscous composition with a pH of about 4 to 5.5 by using a copolymer obtained by polymerizing a (meth)acrylic acid, a (meth)acrylic acid alkyl ester having an alkyl group with 10 to 30 carbon atoms, and additionally, a compound with two or more ethylenically unsaturated groups. More specifically, provided is, for example, a viscous composition comprising (A) a copolymer obtained by polymerizing 100 parts by mass of a (meth)acrylic acid, 0.5 to 5 parts by mass of a (meth)acrylic acid alkyl ester having an alkyl group with 10 to 30 carbon atoms, and 0.001 to 0.2 parts by mass of a compound with two or more ethylenically unsaturated groups, (B) a carboxylic acid metal salt, and (C) a carboxylic acid; and having a pH of 4 to 5.5, and a viscosity of 1000 to 50000 mPa.Math.s.

Provided is a technique for preparing an excellent viscous composition with a pH of about 4 to 5.5 by using a copolymer obtained by polymerizing a (meth)acrylic acid, a (meth)acrylic acid alkyl ester having an alkyl group with 10 to 30 carbon atoms, and additionally, a compound with two or more ethylenically unsaturated groups. More specifically, provided is, for example, a viscous composition comprising (A) a copolymer obtained by polymerizing 100 parts by mass of a (meth)acrylic acid, 0.5 to 5 parts by mass of a (meth)acrylic acid alkyl ester having an alkyl group with 10 to 30 carbon atoms, and 0.001 to 0.2 parts by mass of a compound with two or more ethylenically unsaturated groups, (B) a carboxylic acid metal salt, and (C) a carboxylic acid; and having a pH of 4 to 5.5, and a viscosity of 1000 to 50000 mPa.Math.s.

Provided is an alkyl-modified carboxyl group-containing copolymer with which a neutralized viscous liquid can be prepared which has excellent dispersibility in water, has a viscosity that does not change greatly regardless of addition of an electrolyte, and has high transparency in the presence of an electrolyte. This alkyl-modified carboxyl group-containing copolymer contains: 100 parts by mass of a (meth)acrylic acid; 1.5-4.5 parts by mass of a (meth)acrylic acid alkyl ester, in which an alkyl group has 18-24 carbon atoms; and 0-0.1 parts by mass of a compound having two or more ethylenically unsaturated groups, wherein the copolymer contains 1.5-4.5 parts by mass of a nonionic surfactant.

Provided is an alkyl-modified carboxyl group-containing copolymer with which a neutralized viscous liquid can be prepared which has excellent dispersibility in water, has a viscosity that does not change greatly regardless of addition of an electrolyte, and has high transparency in the presence of an electrolyte. This alkyl-modified carboxyl group-containing copolymer contains: 100 parts by mass of a (meth)acrylic acid; 1.5-4.5 parts by mass of a (meth)acrylic acid alkyl ester, in which an alkyl group has 18-24 carbon atoms; and 0-0.1 parts by mass of a compound having two or more ethylenically unsaturated groups, wherein the copolymer contains 1.5-4.5 parts by mass of a nonionic surfactant.

A cross-linked polymer including a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (1):

##STR00001##

wherein R.sup.1 represents an alkyl group having 1 to 5 carbons and n represents an integer from 1 to 5; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (2):

##STR00002##

wherein R.sup.2 represents a divalent saturated hydrocarbon group having 2 to 17 carbons, containing an aromatic ring; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and the polymers are cross-linked to each other.

A cross-linked polymer including a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (1):

##STR00001##

wherein R.sup.1 represents an alkyl group having 1 to 5 carbons and n represents an integer from 1 to 5; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (2):

##STR00002##

wherein R.sup.2 represents a divalent saturated hydrocarbon group having 2 to 17 carbons, containing an aromatic ring; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and the polymers are cross-linked to each other.