A polyester resin composition according to the present invention includes a polyester polyol having a glycerol skeleton and a curing agent, wherein 5 percent by mass or more of glycerol residue of the polyester polyol is contained in the polyester resin composition. The resin composition can provide an adhesive exhibiting an excellent adhesive force. The adhesive has a gas barrier property or a water vapor barrier property and, therefore, a gas barrier or water vapor barrier film can be provided by using the adhesive.

A polyester resin composition according to the present invention includes a polyester polyol having a glycerol skeleton and a curing agent, wherein 5 percent by mass or more of glycerol residue of the polyester polyol is contained in the polyester resin composition. The resin composition can provide an adhesive exhibiting an excellent adhesive force. The adhesive has a gas barrier property or a water vapor barrier property and, therefore, a gas barrier or water vapor barrier film can be provided by using the adhesive.

A polyester resin composition according to the present invention includes a polyester polyol having a glycerol skeleton and a curing agent, wherein 5 percent by mass or more of glycerol residue of the polyester polyol is contained in the polyester resin composition. The resin composition can provide an adhesive exhibiting an excellent adhesive force. The adhesive has a gas barrier property or a water vapor barrier property and, therefore, a gas barrier or water vapor barrier film can be provided by using the adhesive.

An adhesive agent produced by crosslinking an adhesive agent composition containing a polyester resin (i) having a structural portion derived from a polycarboxylic acid compound (a) and a structural portion derived from a polyol component (b), wherein the polyester resin (i) contains a structural portion derived from at least one selected from the group consisting of a dimer acid compound, a sebacic acid compound, and a dimer diol in a proportion of not less than 60 wt. % based on the weight of the polyester resin (i), wherein the polyol component (b) includes a glycol (b1) having an even carbon number (excluding the dimer diol), wherein the polyester resin (i) has an ester group concentration of not less than 2 mmol/g. The adhesive agent has an adhesive force (α) of not less than 1 N/25 mm as measured under predetermined conditions.

An adhesive agent produced by crosslinking an adhesive agent composition containing a polyester resin (i) having a structural portion derived from a polycarboxylic acid compound (a) and a structural portion derived from a polyol component (b), wherein the polyester resin (i) contains a structural portion derived from at least one selected from the group consisting of a dimer acid compound, a sebacic acid compound, and a dimer diol in a proportion of not less than 60 wt. % based on the weight of the polyester resin (i), wherein the polyol component (b) includes a glycol (b1) having an even carbon number (excluding the dimer diol), wherein the polyester resin (i) has an ester group concentration of not less than 2 mmol/g. The adhesive agent has an adhesive force (α) of not less than 1 N/25 mm as measured under predetermined conditions.

An electrophotographic developer set comprising a toner, and a powder adhesive, wherein the powder adhesive comprises a crystalline polyester resin, and a thermoplastic resin other than the crystalline polyester resin; the amount of the crystalline polyester resin in the powder adhesive is 21% by mass or more; the melting point of the crystalline polyester resin is 55° C. to 100° C.; in a viscoelasticity measurement, where Gt′(100) denotes a storage elastic modulus of the toner at 100° C. and Gb′(100) denotes a storage elastic modulus of the powder adhesive at 100° C., Gb′(100) is 1.0×10.sup.5 Pa or less and Gt′(100)/Gb′(100) is 1.2 or more.

An electrophotographic developer set comprising a toner, and a powder adhesive, wherein the powder adhesive comprises a crystalline polyester resin, and a thermoplastic resin other than the crystalline polyester resin; the amount of the crystalline polyester resin in the powder adhesive is 21% by mass or more; the melting point of the crystalline polyester resin is 55° C. to 100° C.; in a viscoelasticity measurement, where Gt′(100) denotes a storage elastic modulus of the toner at 100° C. and Gb′(100) denotes a storage elastic modulus of the powder adhesive at 100° C., Gb′(100) is 1.0×10.sup.5 Pa or less and Gt′(100)/Gb′(100) is 1.2 or more.

An electrophotographic developer set comprising a toner, and a powder adhesive, wherein the powder adhesive comprises a crystalline polyester resin, and a thermoplastic resin other than the crystalline polyester resin; the amount of the crystalline polyester resin in the powder adhesive is 21% by mass or more; the melting point of the crystalline polyester resin is 55° C. to 100° C.; in a viscoelasticity measurement, where Gt′(100) denotes a storage elastic modulus of the toner at 100° C. and Gb′(100) denotes a storage elastic modulus of the powder adhesive at 100° C., Gb′(100) is 1.0×10.sup.5 Pa or less and Gt′(100)/Gb′(100) is 1.2 or more.

The invention provides a laminated polyester film that is highly transparent, is resistant to blocking, and has excellent adhesion to a hardcoat layer and UV ink. The laminated polyester film contains a polyester film substrate and a coating layer on at least one surface of the polyester film substrate, wherein the coating layer is formed by curing a composition containing a urethane resin with a polycarbonate structure and a branched structure, a crosslinking agent, and a polyester resin.

The invention provides a laminated polyester film that is highly transparent, is resistant to blocking, and has excellent adhesion to a hardcoat layer and UV ink. The laminated polyester film contains a polyester film substrate and a coating layer on at least one surface of the polyester film substrate, wherein the coating layer is formed by curing a composition containing a urethane resin with a polycarbonate structure and a branched structure, a crosslinking agent, and a polyester resin.