Toner, toner set, image transfer sheet, toner storage unit, image forming apparatus, and image forming method

Abstract

] A toner is provided that includes a polyester resin having a structure (A), and contains 26 wt% or more and less than 70 wt% of THF-insoluble organic matter with respect to 100 wt% of all organic components in the toner. The structure (A) includes R1 having three or more binding sites, and R2 in a number identical to the number of binding sites, in which a bond between each binding site of R1 and each R2 is represented by any one of structural formulas 1) to 3) below. 1) R1-NHCONH-R2 2) R1-NHCOO-R2 3) R1-OCONH-R2 In the formulas above, R1 represents an aromatic or aliphatic organic group derived from a trihydric or higher alcohol or derived from a trivalent or higher polyisocyanate, and R2 represents a group derived from a polyester polyol.

Description

[DESCRIPTION][Title of Invention]TONER, TONER SET, IMAGE TRANSFER SHEET, TONER STORAGE UNIT, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD [Technical Field]

[0001] The present disclosure relates to a toner, a toner set, an image transfer sheet, a toner storage unit, an image forming apparatus, and an image forming method.[Background Art]

[0002] In an electrophotographic method of developing an electrostatic latent image with a developer to form a visible image, an electrostatic latent image is formed on an electrostatic latent image bearer (also referred to as a photoconductor) containing a photoconductive material, the electrostatic latent image is developed with a developer containing a toner to form a toner image, and the toner image is transferred onto a transfer material such as paper. Afterwards, the toner image is fixed by applying heat and pressure to form a fixed image.To form a full-color image by an electrophotographic method, a toner set is generally used in which a black toner is combined with toners of three process colors (sometimes simply referred to as process colors), that is, cyan, magenta, and yellow toners.

[0003] In recent years, as color image forming apparatuses employing electrophotographic methods are widely used, the applications of such apparatuses on printed matter have also become more diverse. Particularly in the field of custom-made design consumer goods, there is a growing need for printing by electrophotographic methods on materials that cannot be printed with electrophotographic toner of the background art intended for printing on paper media (materials to which electrophotographic toner of the background art cannot be fixed). Specifically, there is an increasing need to print on fabric media such as uniforms, shoes, and bags of sports teams.

[0004] PTL 1 discloses a thermal transfer print sheet obtained by using a pulverized toner for thermal transfer print sheets, by which it is possible to adhere an image to a printing object by thermal melting on a white fabric without using an adhesive, and which does not damage a pulverizer. [Citation List] [Patent Literature]

[0005] [PTL 1]Japanese Patent No. 5510517[Summary of Invention][Technical Problem]

[0006] Toners used to form a fixed image on a fabric medium are required to have characteristics not observed in toners of the background art used to be fixed to a paper medium. These characteristics include the ability of being sufficiently fixed to fabrics having a large amount of uneven fibers and forming a fixed toner layer that has an appropriate flexibility so that the toner layer can follow the deformation of the fabric. However, there has not yet been found a toner that has excellent flexibility and excellent fixability on flexible recording media such as fabric, and that can conceal the color of the fabric.

[0007] An object of the present invention is to solve the above-mentioned problems in the background art and achieve the following aims. That is, an object of the present invention is to provide a toner that can be sufficiently fixed to a flexible recording medium such as a fabric, to which it is not easy to fix a toner of the background art.[Solution to Problem]

[0008] One aspect of the present invention is a toner that includes a polyester resin having a structure (A), and contains 26 wt% or more and less than 70 wt% of THF-insoluble organic matter with respect to 100 wt% of all organic components in the toner.The structure (A) includes R1 having three or more binding sites, and R2 in a number identical to the number of binding sites, in which a bond between each binding site of R1 and each R2 is represented by any one of structural formulas 1) to 3) below.1) R1-NHCONH-R22) R1-NHCOO-R23) R1-OCONH-R2In the formulas above, R1 represents an aromatic or aliphatic organic group derived from a trihydric or higher alcohol or derived from a trivalent or higher polyisocyanate, and R2 represents a group derived from a polyester polyol.[Advantageous Effects of Invention]

[0009] According to embodiments of the present invention, a toner is provided that can be sufficiently fixed to a flexible recording medium such as a fabric, to which it is not easy to fix a toner of the background art.[Brief Description of Drawings]

[0010] A more complete appreciation of embodiments of the present disclosure and many of the attendant advantages and features thereof can be readily obtained and understood from the following detailed description with reference to the accompanying drawings.[FIG. 1]FIG. 1 is a general configuration diagram illustrating an example of an image forming apparatus of the present embodiment.[FIG. 2]FIG. 2 is a general configuration diagram illustrating another example of an image forming apparatus of the present embodiment.[FIG. 3]FIG. 3 is a general configuration diagram illustrating another example of an image forming apparatus of the present embodiment.[FIG. 4]FIG. 4 is a partially enlarged view of FIG. 3.[FIG. 5]FIG. 5 is a general configuration diagram illustrating an example of a process cartridge.[FIG. 6]FIG. 6 is an image diagram for describing a branched structure of a polyester resin of the background art.[FIG. 7]FIG. 7 is an image diagram for describing a branched structure of a polyester resin defined in the present embodiment.The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views. [Description of Embodiments]

[0011] In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.Referring now to the drawings, embodiments of the present disclosure are described below. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.(Toner)In the present embodiment, a toner contains a polyester resin, preferably further contains a crystalline polyester resin, and further contains other components such as a colorant, if desired.The polyester resin contains a polyester resin having a structure (A) (hereinafter, also referred to as polyester resin A).The structure (A) is a structure including R1 having three or more binding sites and the same number of R2 as the number of binding sites, in which a bond between each binding site of R1 and each R2 is represented by any one of Structural Formulas 1) to 3) below.1) R1-NHCONH-R22) R1-NHCOO-R23) R1-0C0NH-R2In the above-mentioned formulas, R1 represents an aromatic or aliphatic organic group derived from a trihydric or higher alcohol or a trivalent or higher polyisocyanate, and R2 represents a group derived from a polyester polyol.That is, the polyester resin A has a structure in which R2, which is a polyester or a modified polyester moiety, and Rl, which corresponds to a branched structure, are bonded via a urethane or a urea group.

[0012] In the toner of the present embodiment, the polyester resin has a branched structure in the molecular backbone from urethane or urea bonds, and the molecular chain forms a three- dimensional network structure. Therefore, the polyester resin has rubber- like properties by which the polyester resin deforms at low temperatures but does not flow. Thus, the toner has excellent properties by which, even when the toner is printed on fabric, the toner expands and contracts when the fabric expands and contracts or when the fabric is being washed and dried, so that an image is not easily destroyed. Further, the uniform three-dimensional structure of the polyester resin provides high image durability. Even when the glass transition temperature of the polyester resin is very low, it is possible to maintain the heat-resistant storage stability and the high-temperature offset resistance of the toner.

[0013] Moreover, if the network structure is not uniform, the resin is not sufficiently prevented from flowing in coarse portions of the network structure, so that the heat-resistant storage stability deteriorates, and the resin does not have sufficient deformability for dense portions of the network structure, so that the image strength decreases. For example, when a moiety forming a branch is an ester structure (that is, when the moiety of R2 in the structural formula represented by the structure (A) defined in the present application has a branched structure), the branched structure is not uniform, as illustrated in the image diagram of FIG. 6, and thus, the heat-resistant storage stability and the image strength are not completely satisfactory.FIG. 6 is a general diagram of the branched structure of a polyester resin obtained by a synthesis method of the background art.

[0014] On the other hand, in the polyester resin A of the present embodiment, R2 formed by a polyester or a modified polyester moiety is synthesized, and then, can be bonded to Rl via a urethane group or a urea group to form a network structure. Therefore, by keeping the molecular weight distribution of the R2 portion within a narrow range, it is possible to form a uniform network structure.The state of the polyester resin A having the structure (A) defined in the present embodiment is illustrated in the image diagram of FIG. 7. FIG. 7 is a general diagram of the branched structure of a polyester resin obtained by the synthesis method of the present embodiment described below. The linear polyester resin moieties in the R2 portion have uniform length, and thus, the branched structure of the polyester resin is uniform, as illustrated in FIG. 7.As described above, by forming the polyester resin A in a uniform network structure, it is possible to achieve both heat-resistant storage stability of the toner and high image strength. Further, the branched structure moiety of the polyester resin A includes a urethane bond or a urea bond having high cohesive energy, and thus, the polyester resin A functions as a strong crosslinking point. Therefore, even if the polyester resin A has a coarser network structure, the resin is strongly prevented from flowing, and thus, it is possible to obtain both heat- resistant storage stability of the toner and image strength.

[0015] < Polyester Resin A>The polyester resin A has a structure (A), in which R2, formed by a polyester or modified polyester moiety, and Rl, corresponding to a branched structure, are bonded via a urethane group or a urea group.The polyester resin A includes at least any one of a urethane bond and a urea bond in the branched structure moiety. Therefore, the urethane bond or the urea bond serves as a pseudocrosslinking point, and the rubber-like properties of the polyester resin A are enhanced, so that it is possible to manufacture a toner having excellent heat-resistant storage stability and cracking resistance.The polyester resin A contains, as a constituent component, a diol component, and more preferably contains, as a constituent component, a dicarboxylic acid component.

[0016] The polyester resin A is preferably an amorphous polyester resin.

[0017] The polyester resin A is not particularly limited and can be appropriately selected according to a purpose, as long as the polyester resin A is formed by bonding R2 corresponding to a polyester or a modified polyester moiety and Rl corresponding to a branched structure moiety via a urethane group or a urea group.Examples of a method for bonding the above-described Rl and R2 include the following three methods, but are not limited thereto.

[0018] a) A method in which a diol component and a dicarboxylic acid component are subjected to an esterification reaction to prepare a polyester polyol (R2) having a hydroxyl group on a terminal end and the obtained polyester polyol is subjected to a reaction with a trivalent or higher polyisocyanate (Rl). b) A method in which a diol component and a dicarboxylic acid component are subjected to an esterification reaction to prepare a polyester polyol (R2) having a hydroxyl group on a terminal end, the obtained polyester polyol is subjected to a reaction with a divalent polyisocyanate to prepare an isocyanate-modified polyester (R2), and the obtained isocyanate - modified polyester is subjected to a reaction with a trihydric or higher alcohol (Rl). c) A method in which a diol component and a dicarboxylic acid component are subjected to an esterification reaction to prepare a polyester polyol (R2) having a hydroxyl group at aterminal end, the obtained polyester polyol is subjected to a reaction with a divalent polyisocyanate to prepare an isocyanate-modified polyester (R2), and the obtained isocyanate - modified polyester is subjected to a reaction with a trivalent or higher polyisocyanate (Rl) in the presence of pure water.It is also possible to further react the hydroxyl groups remaining in the polyol obtained by any one of the above-described a) to c) with a divalent or higher polyisocyanate to form a polyester prepolymer, which can then be subjected to a reaction with a curing agent in a toner preparation process.It is more preferable that the moiety of R2 is a modified polyester resin modified with isocyanate, because in this case, in the toner preparation process, the prepolymer can be reacted with a curing agent to obtain a urethane bond or a urea bond that function as a strong crosslinking point, to enhance the rubber-like properties of the polyester resin A and provide further excellent heat-resistant storage stability and high-temperature offset resistance.

[0019] To lower the Tg of the polyester resin A and to easily impart deformability at low temperatures, the polyester resin A contains a diol component as a constituent component, and the diol component preferably contains an aliphatic diol having 3 to 12 carbon atoms, and more preferably contains an aliphatic diol having 4 to 12 carbon atoms.

[0020] The polyester resin A preferably contains the aliphatic diol having 3 to 12 carbon atoms in an amount of 50 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more.

[0021] Examples of the aliphatic diol having 3 to 12 carbon atoms include, but are not limited to, 1,3- propanediol, 1,4-butanediol, 2-methyl-l,3-propanediol, 1,5-pentanediol, 3-methyl-l,5- pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol.

[0022] In particular, it is even more preferable that, in the polyester resin A, the diol component is an aliphatic diol having 4 to 12 carbon atoms, the number of carbon atoms included in a portion forming the main chain of the diol component is an odd number, and the diol component has an alkyl group in a side chain.Examples of the aliphatic diol having 4 to 12 carbon atoms and including an alkyl group in the side chain, and in which a portion forming the main chain includes an odd number of carbon atoms include, but are not limited to, aliphatic diols represented by General Formula (1) below.HO-(CRlR2)n-OH ... General Formula (1)In General Formula (1) above, Rl and R2 each independently represent a hydrogen atom and an alkyl group having 1 to 3 carbon atoms, n represents an odd number from 3 to 9. In the n repeating units, Rl may be the same in each unit or may be different. In the n repeating units, R2 may be the same in each unit or may be different.

[0023] To lower the Tg of the polyester resin A and easily impart deformability at low temperatures, the polyester resin A preferably contains 50 mol% or more of an aliphatic diol having 3 to 12 carbon atoms in total in the alcohol components.

[0024] To lower the Tg of the polyester resin A and easily impart deformability at low temperatures, it is preferable that the polyester resin A contains a dicarboxylic acid component as a constituent component, and that the dicarboxylic acid component contains an aliphatic dicarboxylic acid having 4 to 12 carbon atoms.

[0025] The polyester resin A preferably contains 30 mol% or more of the aliphatic dicarboxylic acid having 4 to 12 carbon atoms.

[0026] Examples of the aliphatic dicarboxylic acid having 4 to 12 carbon atoms include, but are not limited to, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid.

[0027] - Diol Component -The diol component is not particularly limited and can be appropriately selected according to a purpose. Examples of the diol component include, but are not limited to, aliphatic diols such as ethylene glycol, 1,2-propylene glycol, 1,3 -propylene glycol, 1,4-butanediol, 2-methyl- 1,3-propanediol, 1,5-pentanediol, 3-methyl-l,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol; diols having an oxyalkylene group such as diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; diol components obtained by adding alkylene oxides, such as ethylene oxide, propylene oxide, and butylene oxide, to alicyclic diols; bisphenols such as bisphenol A, bisphenol F, and bisphenol S; and alkylene oxide adducts of bisphenols obtained by adding alkylene oxides, such as ethylene oxide, propylene oxide, and butylene oxide, to bisphenols. Among these diol components, aliphatic diols having 4 to 12 carbon atoms are preferred.These diols may be used alone or in combination of two or more types.

[0028] - Dicarboxylic Acid Component -The dicarboxylic acid component is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, aliphatic dicarboxylic acids and aromatic dicarboxylic acids. Further, anhydrides, lower alkyl esters (having 1 to 3 carbon atoms), or halides of these dicarboxylic acid components may be used.The aliphatic dicarboxylic acids are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, maleic acid, and fumaric acid.The aromatic dicarboxylic acid is not particularly limited and can be appropriately selected according to a purpose. However, the aromatic dicarboxylic acid is preferably an aromatic dicarboxylic acid having 8 to 20 carbon atoms.The aromatic dicarboxylic acid having 8 to 20 carbon atoms is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. Among these dicarboxylic acids, aliphatic dicarboxylic acids having 4 to 12 carbon atoms are preferred.These dicarboxylic acids may be used alone or in combination of two or more types.

[0029] - Trihydric or Higher Alcohol -The trihydric or higher alcohol is not particularly limited and can be appropriately selected according to a purpose. Examples of the trihydric or higher alcohol include, but are not limited to, trihydric or higher aliphatic alcohols, trivalent or higher polyphenols, and alkylene oxide adducts of trivalent or higher polyphenols.Examples of the trivalent or higher aliphatic alcohol include, but are not limited to, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol.Examples of the trivalent or higher polyphenols include, but are not limited to, trisphenol PA, phenol novolac, and cresol novolac.Examples of the alkylene oxide adducts of trivalent or higher polyphenols include, but are not limited to, alkylene oxide adducts obtained by adding alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to trivalent or higher polyphenols.

[0030] - Polyisocyanate -The polyisocyanate is not particularly limited and can be appropriately selected according to a purpose. Examples of the polyisocyanate include, but are not limited to, diisocyanates and trivalent or higher isocyanates.Examples of the diisocyanates include, but are not limited to, aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, aromatic aliphatic diisocyanates, isocyanurates, and diisocyanates obtained by blocking these compounds with phenol derivatives, oximes, caprolactams, and the like.Examples of the trivalent or higher isocyanates include, but are not limited to, lysine triisocyanate, or a compound obtained by reacting a trihydric or higher alcohol with diisocyanate, and a compound obtained by reacting a polyisocyanate to form an isocyanurate. Among these isocyanates, it is more preferable to use a polyisocyanate having an isocyanurate backbone, because such a compound acts as a stronger crosslinking point and provides better heat-resistant storage stability and high-temperature offset resistance.

[0031] The content of the trivalent isocyanate component is preferably 0.2 mol% or more and 1.0 mol% or less, with respect to the resin component in the organic matter of the toner not soluble in THF. When a crosslinked structure is formed by using a trivalent isocyanate component, the cohesive strength of the molecular chains increases by pseudo-crosslinking caused by the urethane or urea bonds at the crosslinking points, so that the heat-resistant storage stability can be improved even at a low crosslinking density, and a high level of low- temperature fixability can be achieved. When the content of the trivalent isocyanate component is less than 0.2 mol%, the branched structure is not sufficiently formed, and the network structure is formed from non-uniform portions as start points, so that the heat- resistant storage stability and the filming resistance deteriorate. When the content of the trivalent isocyanate component is more than 1.0 mol%, a dense crosslinked structure is formed, and thus, the low-temperature fixability may deteriorate.The aliphatic diisocyanate is not particularly limited and can be appropriately selected according to a purpose. Examples of the aliphatic diisocyanate include, but are not limited to, tetramethylene diisocyanate, hexamethylene diisocyanate, methyl 2,6-diisocyanatocaproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, and tetramethylhexane diisocyanate.The alicyclic diisocyanate is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, isophorone diisocyanate and cyclohexylmethane diisocyanate.The aromatic diisocyanate is not particularly limited and can be appropriately selected according to a purpose. Examples of the aromatic diisocyanate include, but are not limited to, tolylene diisocyanate, diisocyanatodiphenylmethane, 1,5 -naphthylene diisocyanate, 4,4'- diisocyanatodiphenyl, 4,4'-diisocyanato-3,3'-dimethyldiphenyl, 4,4'-diisocyanato-3- methyldiphenylmethane, and 4,4'-diisocyanato-diphenyl ether.The aromatic aliphatic diisocyanate is not particularly limited, may be appropriately selected according to a purpose, and examples thereof include, but are not limited to, a,a,a',a'- tetramethylxylylene diisocyanate.The isocyanurates are not particularly limited and can be appropriately selected according to a purpose. Examples of the isocyanurates include, but are not limited to, tris(isocyanatoalkyl)isocyanurate and tris(isocyanatocycloalkyl)isocyanurate.These polyisocyanates may be used alone or in combination of two or more types.

[0032] - Curing Agent -The curing agent is not particularly limited and can be appropriately selected according to a purpose, as long as the curing agent can react with a polyester prepolymer (a reaction product of the polyester moiety of R2 and the polyisocyanate, that is, a reaction precursor to bereacted with the curing agent) to produce the polyester resin. Examples of the curing agent include, but are not limited to, a compound containing an active hydrogen group.

[0033] — Compound Containing Active Hydrogen Group -The active hydrogen group in the compound containing an active hydrogen group is not particularly limited and can be appropriately selected according to a purpose. Examples of the active hydrogen group include, but are not limited to, a hydroxyl group (an alcoholic hydroxyl group and a phenolic hydroxyl group), an amino group, a carboxyl group, and a mercapto group. These active hydrogen groups may be used alone or in combination of two or more types.

[0034] The compound containing an active hydrogen group is not particularly limited and can be appropriately selected according to a purpose. However, the compound is preferably an amine, because amines can form a urea bond.

[0035] The amines are not particularly limited and can be appropriately selected according to a purpose. Examples of the amines include, but are not limited to, diamines, trivalent or higher amines, amino alcohols, amino mercaptans, amino acids, and amines in which the amino group of these compounds is blocked. These amines may be used alone or in combination of two or more types.Among these amines, diamines and mixed compounds of diamines with small amounts of trivalent or higher amines are preferred.

[0036] The diamines are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, aromatic diamines, alicyclic diamines, and aliphatic diamines. The aromatic diamines are not particularly limited and can be appropriately selected according to a purpose. Examples of the aromatic diamines include, but are not limited to, phenylenediamine, diethyltoluenediamine, and 4,4'- diaminodiphenylmethane. The alicyclic diamines are not particularly limited and can be appropriately selected according to a purpose. Examples of the alicyclic diamines include, but are not limited to, 4,4'-diamino-3,3'-dimethyldicyclohexylmethane, diaminocyclohexane, and isophoronediamine. The aliphatic diamines are not particularly limited and can be appropriately selected according to a purpose. Examples of the aliphatic diamines include, but are not limited to, ethylenediamine, tetramethylenediamine, and hexamethylenediamine.

[0037] The trivalent or higher amines are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, diethylenetriamine and triethylenetetramine.The amino alcohols are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, ethanolamine and hydroxyethylaniline.The amino mercaptans are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, aminoethyl mercaptan and aminopropyl mercaptan.The amino acids are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, aminopropionic acid and aminocaproic acid.The amines in which the amino group is blocked are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, oxazoline compounds and ketimine compounds obtained by blocking the amino group with ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone.

[0038] The glass transition temperature of the polyester resin A is preferably from -60°C to 0°C, and more preferably from -40°C to -20°C.If the glass transition temperature is lower than -60°C, it is not possible to prevent the toner from flowing at low temperatures, so that the heat-resistant storage stability deteriorates, and further, the filming resistance may deteriorate.If the glass transition temperature exceeds 0°C, it is not possible to sufficiently deform the toner by the application of heat and pressure during fixing, and the fixability at low temperatures may be insufficient.In the polyester resin, it is preferable that R1 in Structure (A) has an isocyanurate backbone represented by Structural Formula (I) below, to obtain heat-resistant storage stability and high-temperature offset resistance.[Chem. 1]

[0039] Further, in the polyester resin A, although detailed reasons are not clear, the three- dimensional network structure of the molecules is in a state suitable for achieving fixability at low temperatures, image gloss, heat-resistant storage stability, and offset resistance. Therefore, in Structure (A), it is more preferable that the number of binding sites of R1 is 3.

[0040] Moreover, in the polyester resin A, the organic group of R1 in Structure (A) is preferably an organic group having a low number of carbon atoms, because in this case, it is easy to obtain a uniform network structure, and the organic group is preferably an aliphatic or aromatic organic group having 20 or less carbon atoms.The organic group of R1 may also contain an ester bond.Among these organic groups, the organic group of R1 is preferably an aliphatic organic group or an aliphatic compound containing an ester bond, because in this case, the cohesive strength of the crosslinking points can be adjusted within an appropriate range and it is easy to achieve both high gloss and heat-resistant storage stability.

[0041] The weight average molecular weight of the polyester resin is not particularly limited and may be appropriately selected according to a purpose, but is preferably 20,000 or more and 1,000,000 or less, determined in a measurement by gel permeation chromatography (GPC). The weight average molecular weight of the polyester resin refers to the molecular weight of a reaction product obtained by a reaction of the reactive precursor and the curing agent.If the weight average molecular weight is less than 20,000, the toner is likely to flow at low temperatures, and the heat-resistant storage stability may deteriorate.Further, the viscosity of the toner when being melted may decrease, which may result in poor high-temperature offset resistance.

[0042] It is sufficient that the polyester resin in the present embodiment contains the polyester resin A having the structure (A). The polyester resin A having the structure (A) may be used alone, or another polyester resin (hereinafter also referred to as polyester resin B) may be used in combination with the polyester resin A having the structure (A).

[0043] (THF-Insoluble Organic Matter)When the total amount of organic components in the toner of the present embodiment is defined as 100 wt%, the amount of THF-insoluble organic matter is preferably 26 wt% or more and less than 70 wt%. The THF-insoluble organic matter is mainly derived from the polyester resin A, and can be adjusted by the content of the polyester resin A in the toner. If the amount of the THF-insoluble organic matter is less than 26 wt%, the image strength is insufficient. On the other hand, if the amount of the THF-insoluble organic matter is 70 wt% or more, the organic matter is likely to adhere to the fixed image when the fixed image is dried in a dryer.

[0044] <Glass Transition Temperature (Tglst)>The toner preferably has a glass transition temperature (Tglst) at the first temperature increase in differential scanning calorimetry (DSC) of 20°C or higher and 40°C or lower.In the case of a conventional toner, when the Tg is about 50°C or lower, the toner is likely to aggregate due to temperature changes during transportation and storage during summer or in tropical regions. As a result, the toner may solidify in a toner bottle and adhere to the interior of a developing device. Further, due to the toner getting stuck in the toner bottle, the toner supply may be insufficient, and when the toner adheres to the interior of the developing device, image abnormality easily occurs.The toner of the present embodiment has a lower Tg than conventional toners. However, the polyester resin A, which is a component of the toner having a low Tg and includes the structure (A), is non-linear, and thus, the heat-resistant storage stability can be maintained in the toner of the present embodiment. In particular, when the polyester resin A including the structure (A) has a urethane bond or a urea bond having high cohesive strength, the heat- resistant storage stability is maintained more effectively.

[0045] If the above-described Tglst, that is, the glass transition temperature of the toner, is higher than 40°C, the toner image is likely to crack when the fabric is washed or stretched. If the glass transition temperature of the toner is less than 20°C, images tend to fuse together during drying in a dryer.In a preferred aspect of the present embodiment, the polyester resin contains two types of polyester resins, that is, the polyester resin A having the structure (A) and the polyester resin B, and the toner containing the polyester resin has a Tglst of 20°C or higher and 40°C or lower.

[0046] < Volume Average Particle Diameter >The volume average particle diameter of the toner is not particularly limited and can be appropriately selected according to a purpose, but is preferably 3 pm or more and 18 pm or less, and particularly preferably 8 pm or more and 16 pm or less, to ensure sufficient development.

[0047] (Miscibility of Resins)Further, it is preferable that, in a vertical cross-sectional SEM image of a fixed image of the toner, no separate phases of the different polyester resins A and B can be confirmed, that is, the polyester resins A and B are mixed. If the resins are not mixed with each other, the distribution of the image strength is not uniform, which leads to a cracked interface in the image.

[0048] (Amorphous Polyester Resin B other than Polyester Resin A)The amorphous polyester resin B other than the polyester resin A used in the present embodiment is obtained by condensation polymerization of an alcohol and a carboxylic acid.

[0049] Examples of the alcohol include, but are not limited to, glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol, etherified bisphenols such as 1,4- bis(hydroxymethyl)cyclohexane and bisphenol A, monomers of other dihydric alcohols, and monomers of trihydric or higher poly hydric alcohols.Among these compounds, from the viewpoint of image strength, compounds not containing aromatic diols such as etherified bisphenols including bisphenol A and compounds in which the alcohol component only includes aliphatic diols having 2 to 6 carbon atoms are preferred. Further, the aliphatic diol preferably contains, at least in one part, ethylene glycol or 1,2- propylene glycol.

[0050] Examples of the carboxylic acid component include, but are not limited to, divalent organic acid monomers and trivalent or higher polyvalent carboxylic acid monomers.Examples of the divalent organic acid monomers include, but are not limited to, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, and malonic acid.Examples of the trivalent or higher polyvalent carboxylic acid monomers include, but are not limited to, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4- cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, l,3-dicarboxyl-2-methylenecarboxypropane, and 1,2,7,8-octanetetracarboxylic acid.

[0051] The weight average molecular weight of the amorphous polyester resin B other than the polyester resin A is not particularly limited and can be appropriately selected according to a purpose. However, from the viewpoint of image strength, the weight average molecular weight is preferably 12,000 or more and 100,000 or less, determined in a measurement by gel permeation chromatography (GPC).

[0052] <Crystalline Polyester Resin>In the toner of the present embodiment, in addition to the polyester resin A and the amorphous polyester resin B other than the polyester resin A, a crystalline polyester resin (hereinafter, also referred to as crystalline polyester resin C) can also be used in combination thereto.The crystalline polyester resin C has high crystallinity and therefore exhibits heat-melting properties (sharp melting properties) indicated by a rapid drop in viscosity near the fixing start temperature. By using the crystalline polyester resin C having the properties described above in combination with the polyester resin A and the polyester resin B, it is possible to obtain a toner having both good fixability to fabrics and good image strength.

[0053] The crystalline polyester resin C can be obtained by using a polyhydric alcohol and a polyvalent carboxylic acid or a derivative thereof, such as a polyvalent carboxylic acid, a polycarboxylic anhydride, and a poly carboxy lie ester.In the present embodiment, as described above, the crystalline polyester resin C refers to a resin obtained by using a polyhydric alcohol and a polyvalent carboxylic acid or a derivative thereof, such as a polyvalent carboxylic acid, a polycarboxylic anhydride, and a polycarboxylic ester. A resin obtained by modifying a polyester resin, for example, the polyester resin A, is not included in the crystalline polyester resin.

[0054] By using a crystal analysis X-ray diffractometer (for example, X'Pert Pro MRD by Philips), it is possible to determine whether the crystalline polyester resin C in the present embodiment is a crystalline resin. A measurement method is described below.First, a target sample is ground in a mortar to prepare a sample powder, and the obtained sample powder is applied evenly to a sample holder. Subsequently, the sample holder is set in the diffractometer to perform the measurement and obtain a diffraction spectrum.When the half-width of the peak having the greatest peak intensity among the diffraction peaks obtained in a range of 20° <29 <25° is 2.0 or less, it is determined that the sample is a crystalline sample.In contrast to crystalline polyester resins, polyester resins that do not exhibit the above- mentioned state are referred to as amorphous polyester resins in the present embodiment. The measurement conditions in the X-ray diffraction measurement are mentioned below. (Measurement Conditions)Tension kV: 45 kVCurrent: 40 mAMPSSUpper GonioScanmode: continuousStart angle: 3°End angle: 35°Angle Step: 0.02°Lucident beam opticsDivergence slit: Div slit 1 / 2Diffraction beam opticsAnti scatter slit: As Fixed 1 / 2Receiving slit: Prog rec slit

[0055] - Polyhydric Alcohol -The polyhydric alcohol is not particularly limited and can be appropriately selected according to a purpose. Examples of the polyhydric alcohol include, but are not limited to, diols and trihydric or higher alcohols.Examples of the diols include, but are not limited to, saturated aliphatic diols. Examples of the saturated aliphatic diols include, but are not limited to, linear saturated aliphatic diols andbranched saturated aliphatic diols. Among these, linear saturated aliphatic diols are preferred, and linear saturated aliphatic diols having 2 to 12 carbon atoms are more preferred. Examples of the saturated aliphatic diols include, but are not limited to, ethylene glycol, 1,3- propanediol, 1,4-butanediol, 1,5 -pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11 -undecanediol, 1,12-dodecanediol, 1,13 -tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, and 1,20-eicosanediol. Among these saturated aliphatic diols, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10- decanediol, and 1,12-dodecanediol are preferred to obtain a crystalline polyester resin having high crystallinity and excellent sharp melting properties.Examples of the trihydric or higher alcohol include, but are not limited to, glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These alcohols may be used alone or in combination of two or more types.

[0056] - Polyvalent Carboxylic Acid -The polyvalent carboxylic acid is not particularly limited and can be appropriately selected according to a purpose. Examples of the polyvalent carboxylic acid include, but are not limited to, divalent carboxylic acids and trivalent or higher carboxylic acids.Examples of the divalent carboxylic acids include, but are not limited to, saturated aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, and 1,18- octadecanedicarboxylic acid; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalene-2,6-dicarboxylic acid; and further examples include, but are not limited to, anhydrides of these carboxylic acids and lower (number of carbon atoms from 1 to 3) alkyl esters of these carboxylic acids.Examples of the trivalent or higher carboxylic acids include, but are not limited to, 1,2,4- benzenetricarboxylic acid, 1,2, 5 -benzenetricarboxy lie acid, 1,2,4-naphthalenetricarboxylic acid, and further, anhydrides of these carboxylic acids and lower (number of carbon atoms from 1 to 3) alkyl esters of these carboxylic acids.In addition to the saturated aliphatic dicarboxylic acids and the aromatic dicarboxylic acids, the polyvalent carboxylic acids may include a dicarboxylic acid having a sulfonic acid group. Further, in addition to the saturated aliphatic dicarboxylic acids and the aromatic dicarboxylic acids, the polyvalent carboxylic acids may include a dicarboxylic acid having a double bond. These polyvalent dicarboxylic acids may be used alone or in combination of two or more types.

[0057] The crystalline polyester resin C preferably includes a linear saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a linear saturated aliphatic diol having 2 to 12 carbon atoms. That is, the crystalline polyester resin C preferably includes a constituent unit derived from a saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a constituentunit derived from a saturated aliphatic diol having 2 to 12 carbon atoms. This is preferable, because in this case, the crystalline polyester resin C has high crystallinity and excellent sharp melting properties, and thus, it is possible to obtain excellent fixability at low temperatures.

[0058] The molecular structure of the crystalline polyester resin C can be determined by an NMR measurement from a liquid or solid sample, and further, by X-ray diffraction, GC / MS, LC / MS, and IR measurements. An example of a method includes, but is not limited to, a method of simply detecting, as a crystalline polyester resin, a resin that absorbs at 965 ± 10 cm-1or 990 ± 10 cm-1from 5CH (out-of-plane bending vibration) of an olefin in an infrared absorption spectrum.

[0059] < Other Components >Examples of the other components include, but are not limited to, a release agent, a colorant, a charge control agent, an external additive, a flowability improver, a cleanability improver, and a magnetic material.

[0060] - Release Agent -The release agent that can be used in the present embodiment is not particularly limited and can be appropriately selected according to a purpose. Examples of the release agent include, but are not limited to, liquid paraffin, microcrystalline wax, natural paraffin, synthetic paraffin, polyolefin wax, and partial oxides of these compounds, or aliphatic hydrocarbons such as fluorides and chlorides, animal oils such as beef tallow and fish oil, vegetable oils such as palm oil, soybean oil, rapeseed oil, rice bran wax, and carnauba wax, higher aliphatic alcohols and higher fatty acids such as montan wax, fatty acid amides, fatty acid bisamides, metal soaps such as zinc stearate, calcium stearate, magnesium stearate, aluminum stearate, zinc oleate, zinc palmitate, magnesium palmitate, zinc myristate, zinc laurate, and zinc behenate, fatty acid esters, and polyvinylidene fluoride. These release agents may be used alone or in combination of two or more types. Among these release agents, it is preferable to use at least an ester wax such as a fatty acid ester.

[0061] When the toner contains a maleic acid-modified polyolefin having a polypropylene block in the main chain, if the content of the maleic acid-modified polyolefin is high, it may not be possible to separate the toner from the fixing roller (or the fixing belt) during fixing, and thus, a waste sheet jam may occur. However, this problem can be resolved by adding an ester wax as the release agent. Further, the ester wax can be finely dispersed in the maleic acid- modified polyolefin having a polypropylene block in the main chain.

[0062] The content of the release agent in the toner is not particularly limited and can be appropriately selected according to a purpose. However, the content is preferably from 0.1 to 8.0 mass%, and more preferably from 1.0 to 6.0 mass%. When the content of the releaseagent is 0.1 mass% or more, the toner and the fixing roller (or the fixing belt) can be separated from each other during fixing, and thus, waste sheet jams can be prevented. When the content of the release agent is 8.0 mass% or less, the toner can be sufficiently fixed to the plastic film.

[0063] - Colorant -The colorant used in the toner of the present embodiment is not particularly limited, and any commonly used colorant can be appropriately selected and used. Depending on the color of the colorant, a black toner, a cyan toner, a magenta toner, a yellow toner, a white toner, a green toner, a blue toner, and the like can be formed.

[0064] Colorants used in a black toner are not particularly limited and can be appropriately selected according to a purpose. However, preferred examples include, but are not limited to, carbon black used alone, and a mixture of carbon black as a main component with copper phthalocyanine, in which the hue and brightness are adjusted.Colorants used in a cyan toner are not particularly limited and can be appropriately selected according to a purpose. However, preferred examples include, but are not limited to, copper phthalocyanine, which serves as Pigment Blue 15:3, or a mixture of the above-mentioned colorants and aluminum phthalocyanine.Colorants used in a magenta toner are not particularly limited and can be appropriately selected according to a purpose. However, Pigment Red 53: 1, Pigment Red 81, Pigment Red 122, and Pigment Red 269 can be used alone or in combination with each other.Colorants used in a yellow toner are not particularly limited and can be appropriately selected according to a purpose. However, Pigment Yellow 74, Pigment Yellow 155, Pigment Yellow 180, and Pigment Yellow 185 can be used alone or in combination with each other. Among these yellow colorants, it is preferable to use Pigment Yellow 185 alone or a mixture of Pigment Yellow 185 and Pigment Yellow 74 to obtain color saturation and storability.Colorants used in a white toner are not particularly limited and can be appropriately selected according to a purpose. For example, colorants obtained by treating the surface of titanium dioxide with silicon, zirconia, aluminum, polyol, and the like can be used. Further, organic white pigments can also be used.Colorants used in a green toner are not particularly limited and can be appropriately selected according to a purpose. For example, Pigment Green 7 and the like can be used, but safety needs to be ensured.Colorants used in a blue toner are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, Pigment Blue 15: 1 and Pigment Violet 23.

[0065] When a toner image formed by the toner of the present embodiment is used as a layer (underlayer) contacting a peelable support body or a flexible recording medium, a conventional toner can be used to form an image on an upper layer of the layer.Further, the toner of the present embodiment has rubber elasticity, so that a printed image is less likely to crack when being pulled, bent, or during laundering. From this viewpoint and from the viewpoint of not impairing the color tone of the toner superimposed on top, when a toner image formed by the toner of the present embodiment is used as an underlayer, the toner is preferably achromatic (white or colorless).

[0066] The colorant may also be compounded with a resin to be used as a masterbatch. Examples of resins to be used in manufacturing a masterbatch or to be kneaded together with a masterbatch include, but are not limited to, the other polyester resins mentioned above, and further, polymers of styrene or substitutes thereof such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene; styrene -based copolymers such as styrene-p-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene-methyl acrylate copolymers, styrene-ethyl acrylate copolymers, styrenebutyl acrylate copolymers, styrene-octyl acrylate copolymers, styrene-methyl methacrylate copolymers, styrene-ethyl methacrylate copolymers, styrene -butyl methacrylate copolymers, styrene-a-chloromethyl methacrylate copolymers, styrene- acrylonitrile copolymers, styrene - vinyl methyl ketone copolymers, styrene -butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers, styrene-maleic acid copolymers, and styrene-maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resins, epoxy polyol resins, polyurethanes, polyamides, polyvinyl butyral, polyacrylic acid resins, rosin, modified rosin, terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffin, and paraffin wax. These resins may be used alone or in combination of two or more types.

[0067] — Color Toner —A toner image formed by the toner of the present embodiment may be used as a layer (underlayer) contacting a peelable support body or a flexible recording medium, and when a conventional toner is used to form an image on an upper layer of the layer, a color toner may be used as the conventional toner. The color toner contains a binder resin and the abovedescribed colorant. Depending on the color of the colorant, it is possible to form a black toner, a cyan toner, a magenta toner, a yellow toner, a white toner, a green toner, a blue toner, and the like.

[0068] The binder resin contained in the color toner is not particularly limited and can be appropriately selected according to a purpose, as long as the color toner has good fixability to the toner image formed by the toner of the present embodiment.

[0069] - Charge Control Agent -The charge control agent is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, nigrosine dyes, triphenylmethane dyes, metal complex dyes containing chromium, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorinemodified quaternary ammonium salts), alkylamides, phosphorus alone or as a compound, tungsten alone or as a compound, fluorine-based activators, metal salts of salicylic acid, and metal salts of derivatives of salicylic acid.Specific examples of the charge control agent include, but are not limited to, BONTRON 03 which is a nigrosine dye, BONTRON P-51 which is a quaternary ammonium salt, BONTRON S-34 which is a metal-containing azo dye, the oxynaphthoic acid metal complex E-82, the salicylic acid metal complex E-84, and the phenol condensate E-89 (all manufactured by Orient Chemical Industries Co., Ltd.), TP-302 and TP-415 which are quaternary ammonium salt molybdenum complexes (both manufactured by Hodogaya Chemical Co., Ltd.), LRA-901, LR-147 which is a boron complex (manufactured by Japan Carlit Co., Ltd.), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymer compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts.These charge control agents may be melt-kneaded together with the masterbatch and the resin, and then, dissolved and dispersed. Alternatively, the charge control agents may be directly dissolved and dispersed in an organic solvent and then added, or may be fixed on a toner surface after toner particles are formed.

[0070] - External Additives -In the toner of the present embodiment, inorganic fine particles and the like can be used as an external additive.The inorganic fine particles used as external additives in the present embodiment are not particularly limited and can be appropriately selected according to a purpose. Examples of the inorganic fine particles include, but are not limited to, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these inorganic fine particles, silica, alumina, and titanium oxide are preferred.The inorganic fine particles may be subjected to a surface treatment using a hydrophobicity treatment agent. The hydrophobicity treatment agent is not particularly limited and can be appropriately selected according to a purpose. However, preferred examples of surface treatment agents include, but are not limited to, silane coupling agents, silylation agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, and aluminum coupling agents. Further, it is possible to obtain a sufficient effect by using silicone oil as a hydrophobicity treatment agent.

[0071] <Method of Calculating and Method of Analyzing Various Properties of Toner and Constituent Components of Toner>The SP value, Tg, the acid value, the hydroxyl value, the molecular weight, and the melting point of the polyester resin, the crystalline polyester resin, and the release agent may each be measured. However, the constituent components may be separated from the actual toner by gel permeation chromatography (GPC) or the like to calculate, for each of the separated constituent components, the SP value, Tg, the molecular weight, the melting point, and the mass ratio of the constituent components by the analytical methods described below.

[0072] The constituent components can each be separated by GPC using the following method, for example.In a GPC measurement using tetrahydrofuran (THF) as the mobile phase, the eluate is fractionated by using a fraction collector or the like, and fractions corresponding to desired molecular weight portions among the total area of the elution curve are combined.

[0073] The combined eluate is concentrated and dried by using an evaporator or the like, and then, the solid content is dissolved in a deuterated solvent such as deuterated chloroform or deuterated THF, to perform an1H-NMR measurement. Thus, the ratio of the constituent monomers of the resin in the eluted components is calculated from the integral ratios of the elements.

[0074] In another method, the eluate is concentrated, and then, subjected to hydrolysis using sodium hydroxide or the like. The decomposition products are qualitatively and quantitatively analyzed by high-performance liquid chromatography (HPLC) or the like to calculate the ratio of the constituent monomers.

[0075] Note that, in a case where, in the method of manufacturing the toner, toner base particles are formed while generating a polyester resin by an extension reaction and / or a cross-linking reaction between the non-linear reactive precursor and the curing agent, the components may be separated from the actual toner by GPC or the like to determine the Tg and the like of the polyester resin. Alternatively, a polyester resin may be synthesized separately by an extension reaction and / or a cross-linking reaction between the non-linear reactive precursor and the curing agent, to measure the Tg and the like of the synthesized polyester resin.

[0076] <<Means for Separating Constituent Components of Toner>>An example of a means used for separating the components when analyzing the toner will be described in detail below.First, 1 g of the toner is filled into 100 mL of THF, and the mixture is stirred for 30 minutes at 25 °C to obtain a solution in which soluble components are dissolved.The solution is filtered through a membrane filter having openings of 0.2 pm to obtain a portion of the toner soluble in THF.Next, the soluble portion is dissolved in THF to prepare a sample for GPC measurement, and the sample is injected into the GPC used for measuring the molecular weight of each of the above-mentioned resins.On the other hand, a fraction collector is placed at an eluate discharge port of the GPC to collect the eluate at predetermined counts, and the eluate is collected for each 5% of the area ratio from the elution start in the elution curve (the rise of the curve).Next, for each elution fraction, 30 mg of the sample is dissolved in 1 mL of deuterated chloroform, and 0.05 vol% of tetramethylsilane (TMS) is added as a standard substance.The solution is filled into a glass tube for NMR measurement having a diameter of 5 mm, and a nuclear magnetic resonance apparatus (JNM-AL400 manufactured by JEOL Ltd.) is used at a temperature of 23°C to 25°C at 128 integrations to obtain a spectrum.The monomer composition and the ratio of the constituent components of the polyester resin, the crystalline polyester resin, and the like contained in the toner can be determined from the peak integral ratio in the obtained spectrum.

[0077] For example, the peaks are identified as described below, and the component ratios of the constituent monomers are determined from the integral ratios.Examples for identifying peaks may include, for example,Vicinity of 8.25 ppm: peak originating from benzene ring of trimellitic acid (corresponding to one hydrogen atom)Vicinity of 8.07 ppm to 8.10 ppm: peak originating from benzene ring of terephthalic acid (corresponding to four hydrogen atoms)Vicinity of 7.1 ppm to 7.25 ppm: peak originating from benzene ring of bisphenol A (corresponding to four hydrogen atoms)Vicinity of 6.8 ppm: peak originating from benzene ring of bisphenol A (corresponding to four hydrogen atoms) and peak originating from double bond of fumaric acid (corresponding to two hydrogen atoms)Vicinity of 5.2 ppm to 5.4 ppm: peak originating from methine of propylene oxide adduct of bisphenol A (corresponding to one hydrogen atom)Vicinity of 3.7 ppm to 4.7 ppm: peak originating from methylene of propylene oxide adduct of bisphenol A (corresponding to two hydrogen atoms) and peak originating from methylene of ethylene oxide adduct of bisphenol A (corresponding to four hydrogen atoms)Vicinity of 1.6 ppm: peak originating from methyl group of bisphenol A (corresponding to six hydrogen atoms).

[0078] For example, as a result of identifying the peaks, an extracted product collected in a fraction containing 90% or more of the polyester resin A having the structure (A), can be treated as the polyester resin A having the structure (A).Similarly, an extracted product collected in a fraction containing 90% or more of the other polyester resin B can be treated as the polyester resin B.Further, an extracted product collected in a fraction containing 90% or more of the crystalline polyester resin C can be treated as the crystalline polyester resin C.

[0079] << Analysis of Organic Matter of Toner Not Soluble in THF>> THF-insoluble organic matter in the toner can be extracted as described below, for example. One part of toner is added to 40 parts of THF and the mixture is refluxed for 6 hours. Subsequently, insoluble components are precipitated by using a centrifuge to separate the insoluble components and the supernatant. The insoluble components are dried at 40°C for 20 hours to obtain THF-insoluble organic matter. The THF-insoluble organic matter corresponds to a non-linear polyester resin. Therefore, the THF-insoluble organic matter contains a plurality of structural moieties derived from trivalent isocyanate.The composition of the THF-insoluble organic matter can be analyzed by an NMR measurement from a liquid or solid sample, and further, by X-ray diffraction, GC / MS, LC / MS, and IR measurements.A simultaneous pyrolysis methylation GC-MS method using a methylation reagent can simply be used to perform analysis by the following method, for example.Device name: Shimadzu QP2010 FRONTIER LAB Py2020DData analysis software: GCMS solution manufactured by Shimadzu Corporation Heating temperature: 280°CPyrolysis reaction temperature: 300°CColumn name: Ultra ALLOY-5, L = 30 m, ID = 0.25 mm, Film = 0.25 pmTemperature in thermostatic chamber: 50°C (maintained for 1 minute) at 10°C / min to 330°C (maintained for 11 minutes)Carrier gas: 53.6 kPa kept constant, He 1.0 mL / minInjection mode: Split (1: 100)Ionization method: El method (70 eV) Measurement mode: Scan mode Library: NIST 20 MASS SPECTRAL

[0080] <<Method of Measuring Melting Point and Glass Transition Temperature (Tg)>>The melting point and the glass transition temperature (Tg) in the present embodiment can be measured, for example, by using a differential scanning calorimeter (DSC) system (“Q-200”, manufactured by TA Instruments).Specifically, the melting point and the glass transition temperature of a target sample can be measured by the following procedure.First, about 5.0 mg of a target sample is fillet into a sample container made of aluminum, and the sample container is placed on a holder unit and set in an electric furnace. Next, in a nitrogen atmosphere, the sample is heated from -80°C to 150°C at a heating rate of 10°C / min(first temperature increase). Afterwards, the sample is cooled from 150°C to -80°C at a cooling rate of 10°C / min, and then, heated again to 150°C at a heating rate of 10°C / min (second temperature increase). During each of the first temperature increase and the second temperature increase, a DSC curve is measured by using a differential scanning calorimeter (“Q-200”, manufactured by TA Instruments).

[0081] From the obtained DSC curves, the DSC curve at the first temperature increase can be selected by using the analysis program in the Q-200 system, to determine the glass transition temperature of the target sample at the first temperature increase. Similarly, the DSC curve at the second temperature increase can be selected to determine the glass transition temperature of the target sample at the second temperature increase.

[0082] Further, from the obtained DSC curves, the DSC curve during the first temperature increase can be selected by using the analysis program in the Q-200 system, to determine the endothermic peak top temperature at the first temperature increase of the target sample as the melting point. Similarly, the DSC curve at the second temperature increase can be selected, to determine the endothermic peak top temperature during the second temperature increase of the target sample as the melting point.

[0083] Herein, when a toner is used as the target sample, the glass transition temperature at the first temperature increase is defined as Tglst, and the glass transition temperature at the second temperature increase is defined as Tg2nd.

[0084] In the present specification, the endothermic peak top temperature and Tg during the second temperature increase are defined as the melting point and Tg of each sample, that is, the glass transition temperature and the melting point of the polyester resin, the crystalline polyester resin, and other components such as the release agent, unless otherwise specified.

[0085] <<Method of Measuring Particle Size DistributionsThe volume average particle diameter (D4) and the number average particle diameter (Dn) of the toner, and the ratio thereof (D4 / Dn) can be measured by using, for example, a COULTER COUNTER TA-II or a COULTER MULTISIZER II (both manufactured by Coulter Inc.). In the present embodiment, a COULTER MULTISIZER II was used.The measurement method is described below.First, 0.1 mL to 5 mL of a surfactant (preferably polyoxyethylene alkyl ether (a nonionic surfactant)) is added as a dispersant to a volume of 100 mL to 150 mL of an aqueous electrolyte solution. The aqueous electrolyte solution is obtained by using high-grade sodium chloride to prepare a 1 mass% aqueous solution of NaCl. For example, it is possible to use an ISOTON-II (manufactured by Coulter Inc.). Subsequently, 2 mg to 20 mg of the sample to be measured is added.The aqueous electrolyte solution in which the sample is suspended is dispersed during about 1 to 3 minutes by using an ultrasonic disperser. The volume and the number of the toner particles or the toner are measured by using a measurement device having an aperture of 100 pm as an aperture, and the volume distribution and the number distribution are calculated. From the obtained distributions, it is possible to determine the volume average particle diameter (D4) and the number average particle diameter (Dn) of the toner.As the channels, thirteen channels are used, that is, 2.00 pm or more and less than 2.52 pm; 2.52 pm or more and less than 3.17 pm; 3.17 pm or more and less than 4.00 pm; 4.00 pm or more and less than 5.04 pm; 5.04 pm or more and less than 6.35 pm; 6.35 pm or more and less than 8.00 pm; 8.00 pm or more and less than 10.08 pm; 10.08 pm or more and less than 12.70 pm; 12.70 pm or more and less than 16.00 pm; 16.00 pm or more and less than 20.20 pm; 20.20 pm or more and less than 25.40 pm; 25.40 pm or more and less than 32.00 pm; and 32.00 pm or more and less than 40.30 pm. The target particles are particles having a particle diameter of 2.00 pm or more and less than 40.30 pm.

[0086] <<Measurement of Molecular Weight>>The molecular weight of each of the constituent components of the toner can be measured by the following method, for example.Gel permeation chromatography (GPC) measurement device: GPC-8220GPC (manufactured by Tosoh Corporation)Column: TSKgel Super HZM-H 15 cm triple column (manufactured by Tosoh Corporation) Temperature: 40°CSolvent: Tetrahydrofuran (THF)Flow rate: 0.35 mL / minSample: 0.4 mL of 0.15 mass% sample injectedPretreatment of sample: Toner is dissolved in tetrahydrofuran (THF) (containing a stabilizer, manufactured by Wako Pure Chemicals, Ltd.) at 0.15 mass%, and then, filtered through a 0.2 pm fdter, to use the fdtrate as a sample.100 pL of the THF sample solution is injected and measured.In measuring the molecular weight of the sample, the molecular weight distribution of the sample is calculated from the relationship between the count number and the logarithmic value of a calibration curve prepared by using several types of monodispersed polystyrene standard samples.SHODEX STANDARD No. S-7300, S-210, S-390, S-875, S-1980, S-10.9, S-629, S-3.0, and S-0.580 manufactured by Showa Denko K.K. are used as polystyrene standard samples for preparing the calibration curve.A refractive index (RI) detector is used as the detector.

[0087] <Method of Manufacturing Toner>The method of manufacturing the toner is not particularly limited and can be appropriately selected according to a purpose. However, it is preferable that the toner contains the polyester resin, preferably further contains the crystalline polyester resin, and further, if desired, the toner is granulated by dispersing an oil phase containing the above-mentioned release agent, the colorant, and the like, in an aqueous medium. In particular, it is more preferable that the polyester resin contains two types of polyester resins, that is, the polyester resin A having the structure (A) and the other polyester resin B.The toner contains, as the polyester resin A, a polyester resin which is the above-described polyester prepolymer (a reaction product of the polyester moiety of R2 and the polyisocyanate, that is, a reaction precursor to be reacted with a curing agent), and the other polyester resin which does not have a urethane bond or a urea bond. Preferably, the toner contains the crystalline polyester resin. Moreover, if desired, the toner is granulated by dispersing an oil phase containing the above-mentioned curing agent, the release agent, the colorant, and the like, in an aqueous medium.

[0088] An example of the method of manufacturing such a toner is a known dissolution suspension method. As an example of the method of manufacturing the toner, a method of forming toner base particles while producing the polyester resin A having the structure (A) by an extension reaction and / or a cross-linking reaction between the polyester prepolymer and the curing agent will be described below. Such a method includes preparing an aqueous medium, preparing an oil phase containing the toner material, emulsifying or dispersing the toner material, and removing the organic solvent.

[0089] - Preparation of Aqueous Medium (Aqueous Phase) -For example, the aqueous medium can be prepared by dispersing resin particles in an aqueous medium. The amount of the resin particles added to the aqueous medium is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 0.5 parts by mass to 10 parts by mass with respect to 100 parts by mass of the aqueous medium.

[0090] The aqueous medium is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, water, a solvent miscible with water, and a mixture thereof. These aqueous media may be used alone or in combination of two or more types. Among these aqueous media, water is preferred.

[0091] The solvent miscible in water is not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, alcohol, dimethylformamide, tetrahydrofuran, CELLOSOLVE solvents, and lower ketones. The alcohol is not particularly limited, can be appropriately selected according to a purpose, and examples of the alcohol include, but are not limited to, methanol, isopropanol, and ethylene glycol. The lower ketones are not particularly limited, can be appropriately selectedaccording to a purpose, and examples thereof include, but are not limited to, acetone and methyl ethyl ketone.

[0092] - Preparation of Oil Phase -The oil phase containing the toner material may be prepared by dissolving or dispersing the toner materials in an organic solvent, where the toner materials include at least the polyester prepolymer, the other polyester resin, and the crystalline polyester resin, and if desired, further contain the curing agent, the release agent, the colorant, and the like.

[0093] The organic solvent is not particularly limited and can be appropriately selected according to a purpose. However, an organic solvent having a boiling point of less than 150°C is preferred to easily remove the organic solvent.

[0094] The organic solvent having a boiling point of less than 150°C is not particularly limited and can be appropriately selected according to a purpose. Examples thereof include, but are not limited to, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2- dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. These organic solvents may be used alone or in combination of two or more types.

[0095] Among these organic solvents, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon tetrachloride, and the like are preferable, and ethyl acetate is more preferable.

[0096] - Emulsion or Dispersion -The toner materials can be emulsified or dispersed by dispersing the oil phase containing the toner materials in the aqueous medium. When the toner materials are emulsified or dispersed, the polyester resin A having the structure (A) is formed by an extension reaction and / or a cross-linking reaction between the curing agent and the polyester prepolymer.

[0097] The polyester resin A having the structure (A) can be prepared, for example, by methods (1) to (3) described below.(1) A method in which an oil phase containing the polyester prepolymer and the curing agent is emulsified or dispersed in an aqueous medium, and the curing agent and the polyester prepolymer are subjected to an extension reaction and / or a cross-linking reaction in the aqueous medium, to prepare the polyester resin A having a structure (A).(2) A method in which an oil phase containing the polyester prepolymer is emulsified or dispersed in an aqueous medium to which the curing agent is added in advance, and the curing agent and the polyester prepolymer are subjected to an extension reaction and / or across-linking reaction in an aqueous medium, to prepare the polyester resin A having the structure (A).(3) A method in which an oil phase containing the polyester prepolymer is emulsified or dispersed in an aqueous medium, the curing agent is added to the aqueous medium, and the curing agent and the polyester prepolymer are subjected to an extension reaction and / or a cross-linking reaction from the particle interface in the aqueous medium, to prepare the polyester resin A having the structure (A).Note that, when the curing agent and the polyester prepolymer are subjected to an extension reaction and / or a cross-linking reaction from the particle interface, the polyester resin A having the structure (A) is preferentially formed on the surface of the toner being produced, and a concentration gradient of the polyester resin A having the structure (A) can be provided in the toner.

[0098] The reaction conditions (the reaction time and the reaction temperature) for producing the polyester resin A having the structure (A) are not particularly limited and can be appropriately selected depending on the combination of the curing agent and the polyester prepolymer.The reaction time is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 10 minutes to 40 hours, and more preferably from 2 hours to 24 hours.The reaction temperature is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 0°C to 150°C, and more preferably from 40°C to 98°C.A method of stably forming a dispersion liquid containing the polyester prepolymer in the aqueous medium is not particularly limited and may be appropriately selected according to a purpose. Examples of the method include a method in which an oil phase prepared by dissolving or dispersing a toner material in a solvent is added to an aqueous medium phase, and the oil phase is dispersed by shear force.A dispersing machine for dispersing the oil phase is not particularly limited and can be appropriately selected according to a purpose. Examples of the dispersing machine include, but are not limited to, a low-speed shear type dispersing machine, a high-speed shear type dispersing machine, a friction type dispersing machine, a high-pressure jet type dispersing machine, and an ultrasonic dispersing machine.Among these dispersing machines, the high-speed shear type dispersing machine is preferred, because this dispersing machine can control the particle diameter of the dispersion (oil droplets) to a range from 2 pm to 20 pm.When the high-speed shear type dispersing machine is used, the conditions such as the rotation speed, the dispersion time, and the dispersion temperature can be appropriately selected according to a purpose.The rotation speed is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 1,000 rpm to 30,000 rpm, and more preferably from 5,000 rpm to 20,000 rpm.The dispersion time is not particularly limited and can be appropriately selected according to a purpose. However, in the case of a batch method, the dispersion time is preferably from 0.1 minutes to 5 minutes.The dispersion temperature is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 0°C to 150°C, and more preferably from 40°C to 98°C when applying pressure. In general, when the dispersion temperature is higher, it is easier to disperse components.The amount of the aqueous medium being used to emulsify or disperse the toner materials is not particularly limited and can be appropriately selected according to a purpose. However, the amount is preferably from 50 parts by mass to 2,000 parts by mass, and more preferably from 100 parts by mass to 1,000 parts by mass, with respect to 100 parts by mass of the toner materials.If the amount of the aqueous medium being used is less than 50 parts by mass, the toner materials may be poorly dispersed, and it may not be possible to obtain toner base particles having a predetermined particle diameter. If the amount of the aqueous medium being used is more than 2,000 parts by mass, the manufacturing costs may increase.

[0099] When the oil phase containing the toner materials is emulsified or dispersed, it is preferable to use a dispersant to stabilize the dispersion such as oil droplets, form a desired shape, and obtain a narrow particle size distribution.The dispersant is not particularly limited and can be appropriately selected according to a purpose. Examples of the dispersant include, but are not limited to, surfactants, inorganic compound dispersants poorly soluble in water, and polymer-based protective colloids. These dispersants may be used alone or in combination of two or more types. Among these dispersants, surfactants are preferred.The surfactants are not particularly limited and can be appropriately selected according to a purpose. For example, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, and the like can be used.The anionic surfactants are not particularly limited, can be appropriately selected according to a purpose, and examples thereof include, but are not limited to, alkylbenzene sulfonate, a- olefin sulfonate, and phosphoric acid ester. Among these anionic surfactants, surfactants having a fluoroalkyl group are preferred.In the extension reaction and / or the cross-linking reaction for producing the polyester resin A having the structure (A), a catalyst may be used.The catalyst is not particularly limited and can be appropriately selected according to a purpose. Examples of the catalyst include, but are not limited to, dibutyltin laurate and dioctyltin laurate.

[0100] - Removal of Organic Solvent -A method of removing the organic solvent from the dispersion liquid such as emulsified slurry is not particularly limited and can be appropriately selected according to a purpose. Examples of the method include, but are not limited to, a method of gradually increasing the temperature of the entire reaction system to evaporate the organic solvent in the oil droplets, and a method of spraying the dispersion liquid into a dry atmosphere to remove the organic solvent in the oil droplets.After the organic solvent is removed, the toner base particles are formed. The toner base particles may be washed, dried, and the like, and may further be subjected to classification and the like. In the classification, a fine particle portion may be separated in a liquid by using a cyclone, a decanter, or centrifugal separation. Alternatively, a classification operation may be implemented after drying.The obtained toner base particles may be mixed with particles of the external additive, the charge control agent, and the like. At this time, by applying a mechanical impact force, it is possible to prevent the particles of the external additive and the like from detaching from the surface of the toner base particles.A method of applying the mechanical impact force is not particularly limited and can be appropriately selected according to a purpose. Examples of the method include, but are not limited to, a method of applying an impact force to the mixture by using a blade rotating at high speed, and a method of introducing the mixture into a high-speed air stream and accelerating the mixture to cause particles to collide with each other or with an appropriate collision plate.A device used in the above-described methods is not particularly limited and can be appropriately selected according to a purpose. Examples of the device include, but are not limited to, ANGMILL (manufactured by Hosokawa Micron Corporation), a device obtained by modifying an I-type mill (manufactured by Nippon Pneumatic Mfg. Co., Ltd.) to reduce the pulverizing air pressure, a HYBRIDIZATION SYSTEM (manufactured by Nara Machinery, Co., Ltd.), a KRYPTRON SYSTEM (manufactured by Kawasaki Heavy Industries, Ltd.), and an automatic mortar.

[0101] (Developer)The developer of the present embodiment contains at least the toner, and if desired, contains other components such as a carrier that are appropriately selected.Therefore, the developer has excellent transferability, chargeability, and the like, and can stably form images of high quality. The developer may be a one-component developer or a two-component developer. However, when used in a high-speed printer and the like responding to the increased information processing speed in recent years, a two-component developer is preferred, because such a developer provides a longer service life.When the developer is used as a one-component developer, and even if the toner is being consumed and resupplied, the particle diameter of the toner varies little, there is little filming of the toner on the developing roller, and the toner hardly fuses with components such as a blade used to obtain a thin layer of the toner. Therefore, it is possible to obtain good and stable developing properties and images, even when the developer is stirred during a long period of time in the developing device.When the developer is used as a two-component developer, the particle diameter of the toner varies little, even when the toner is being consumed and resupplied over a long period of time. Therefore, good and stable developing properties and images can be obtained, even when the toner is stirred during a long period of time in the developing device.

[0102] <Carrier>The carrier is not particularly limited and can be appropriately selected according to a purpose. However, the carrier preferably includes a core material and a resin layer covering the core material.

[0103] - Core Material -The material of the core material is not particularly limited and can be appropriately selected according to a purpose. Examples of the material include, but are not limited to, manganesestrontium based materials having a magnetization of 50 emu / g to 90 emu / g and manganesemagnesium based materials of 50 emu / g to 90 emu / g. To ensure image density, it is preferable to use a highly magnetized material such as iron powder of 100 emu / g or more and magnetite of 75 emu / g to 120 emu / g. Further, it is preferable to use a weakly magnetized material such as a copper-zinc material having a magnetization of 30 emu / g to 80 emu / g, because in this case, it is possible to alleviate the impact of developer in an upright state on the photoconductor, which is advantageous for obtaining high image quality. These materials may be used alone or in combination of two or more types.

[0104] The volume average particle diameter of the core material is not particularly limited and may be appropriately selected according to a purpose, but is preferably from 10 pm to 150 pm, and more preferably from 40 pm to 100 pm.If the volume average particle diameter is less than 10 pm, the amount of fine powder in the carrier increases, and the magnetization per particle decreases, which may cause the carrier to scatter. If the volume average particle diameter exceeds 150 pm, the specific surface area decreases, which may cause the toner to scatter, and in particular, in a full color system that has a large number of solid areas, the reproduction of the solid areas may deteriorate.

[0105] When the toner is used in a two-component developer, the toner may be mixed with the carrier and used as a mixture. The content of the carrier in the two-component developer is not particularly limited and can be appropriately selected according to a purpose. However,the content is preferably 90 parts by mass to 98 parts by mass, and more preferably 93 parts by mass to 97 parts by mass, with respect to 100 parts by mass of the two-component developer.

[0106] The developer of the present embodiment can be suitably used to form images by various types of known electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method.

[0107] (Toner Storage Unit)The term toner storage unit as used herein refers to a portion that stores toner in a unit having a function of storing toner. Here, examples of aspects of the toner storage unit include, but are not limited to, a toner storage container, a developing device, and a process cartridge. The term toner storage container refers to a container storing toner.The term developing device refers to a device including means used for storing and developing the toner.The term process cartridge refers to a cartridge in which at least an image bearer and a developing unit are integrally formed, that stores the toner, and is attachable to and detachable from an image forming apparatus. The process cartridge may further include at least one selected from a charging unit, an exposure unit, and a cleaning unit.

[0108] By mounting the toner storage unit of the present embodiment in an image forming apparatus and forming an image, it is possible to form an image utilizing the characteristics of the toner, such as the suppression of filming, excellent fixability at low temperatures, high-temperature offset resistance, high gloss, high color reproducibility, and heat-resistant storage stability. Specifically, a developer storage container accommodating the developer containing the toner will be described below.

[0109] (Developer Storage Container)The developer storage container according to the present embodiment stores the developer of the present embodiment. The container is not particularly limited and can be appropriately selected from among known containers, and examples thereof include containers having a container main body and a cap.Further, the size, the shape, the structure, the material, and the like of the container main body are not particularly limited. However, the shape is preferably a cylindrical shape or the like, and particularly preferably, a shape in which spiral-shaped irregularities are formed on an inner circumferential surface so that, when the container main body is rotated, the developer therein can move to a side of a discharge port, and a part or all of the spiral- shaped irregularities function as a bellows. Further, the material is not particularly limited, but it is preferable that the material has good dimensional accuracy. Examples of the material include,but are not limited to, resin materials such as polyester resins, polyethylene resins, polypropylene resins, polystyrene resins, polyvinyl chloride resins, polyacrylic acid, polycarbonate resins, ABS resin, and polyacetal resins.The developer storage container can be easily stored, transported, and the like, and has excellent handling properties. Therefore, the developer storage container can be attached to and detached from a process cartridge, an image forming apparatus, and the like, which will be described later, and used for replenishing the developer.

[0110] (Image Forming Apparatus and Image Forming Method)The image forming apparatus of the present embodiment includes at least an electrostatic latent image bearer, an electrostatic latent image forming unit, a developing unit, a transfer unit, and a fixing unit, and further includes other unit, if desired.The image forming method according to the present embodiment includes at least an electrostatic latent image forming step, a developing step, a transfer step, and a fixing step, and may further include other steps, if desired.The image forming method can be suitably performed by the image forming apparatus. The electrostatic latent image forming step can be suitably performed by the electrostatic latent image forming unit. The developing step can be suitably performed by the developing unit. The transfer step can be suitably performed by the transfer unit. The fixing step can be suitably performed by the fixing unit. The other steps can be suitably performed by the other unit.

[0111] <Electrostatic Latent Image Bearer>The material, the structure, and the size of the electrostatic latent image bearer are not particularly limited and can be appropriately selected from known electrostatic latent image bearers. Examples of the material include, but are not limited to, inorganic photoconductors such as amorphous silicon and selenium, and organic photoconductors such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferred, because amorphous silicon provides a long service life.

[0112] Examples of the amorphous silicon photoconductor include, but are not limited to, a photoconductor having a photoconductive layer formed of a-Si, obtained by a method in which a support body is heated to 50°C to 400°C and the photoconductive layer is formed on the support body by a film-forming method such as vacuum deposition, sputtering, ion plating, thermal Chemical Vapor Deposition (CVD), photo CVD, or plasma CVD. Among these methods, plasma CVD, that is, a method in which a gas as a raw material is decomposed by a direct current, high frequency, or a microwave glow discharge to form an a-Si deposition film on a support body, is preferable.

[0113] The shape of the electrostatic latent image bearer is not particularly limited and may be appropriately selected according to a purpose, but a cylindrical shape is preferred. The outer diameter of the electrostatic latent image bearer having the cylindrical shape is not particularly limited and can be appropriately selected according to a purpose. However, the outer diameter is preferably from 3 mm to 100 mm, more preferably from 5 mm to 50 mm, and particularly preferably from 10 mm to 30 mm.

[0114] <Electrostatic Latent Image Forming Unit and Electrostatic Latent Image Forming Step> The electrostatic latent image forming unit is not particularly limited and may be appropriately selected according to a purpose, as long as the electrostatic latent image forming unit is a unit used for forming an electrostatic latent image on the electrostatic latent image bearer. Examples of the electrostatic latent image forming unit include, but are not limited to, a unit including at least a charging member that charges the surface of the electrostatic latent image bearer, and an exposure member that exposes the surface of the electrostatic latent image bearer to light in the form of the image.

[0115] The electrostatic latent image forming step is not particularly limited and can be appropriately selected according to a purpose, as long as the electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image bearer. For example, the surface of the electrostatic latent image bearer may be charged and then, exposed to light in the form of the image, and the electrostatic latent image forming unit may be used in the electrostatic latent image forming step.

[0116] - Charging Member and Charging Process -The charging member is not particularly limited and can be appropriately selected according to a purpose. Examples of the charging member include, but are not limited to, a known contact charging device including a conductive or semiconductive roller, a brush, a film, a rubber blade, or the like, and a non-contact charging device utilizing corona discharge such as a corotron and a scorotron.

[0117] The charging process can be implemented, for example, by using the charging member to apply a voltage to the surface of the electrostatic latent image bearer.

[0118] The shape of the charging member may be any shape, such as a roller, a magnetic brush, and a fur brush, and can be selected according to the specifications and aspects of the image forming apparatus.The charging member is not limited to the contact-type charging member, but it is preferable to use a contact-type charging member, because in this case, it is possible to obtain an image forming apparatus in which the amount of ozone generated from the charging member is reduced.

[0119] - Exposure Member and Exposure Process -The exposure member is not particularly limited and can be appropriately selected according to a purpose, as long as the exposure member can expose, in the form of the image to be formed, the surface of the electrostatic latent image bearer charged by the charging member. Examples of the exposure member include, but are not limited to, copying optical systems, rod lens array systems, laser optical systems, and liquid crystal shutter optical systems.

[0120] The light source used in the exposure member is not particularly limited and can be appropriately selected according to a purpose. Examples of the light source include, but are not limited to, general light-emitting devices such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light-emitting diodes (LEDs), semiconductor lasers (LDs), and electroluminescence (EL) sources.

[0121] To emit only light in a desired wavelength region, various types of filters can be used, such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter.

[0122] The exposure process can be implemented, for example, by using the above-described exposure member to expose the surface of the electrostatic latent image bearer in the form of the image.

[0123] In the present embodiment, a back-light method may be adopted in which the electrostatic latent image bearer is exposed to light in the form of an image from the back side.

[0124] <Developing Unit and Developing Step>The developing unit is not particularly limited and can be appropriately selected according to a purpose, as long as the developing unit is a unit used for developing the electrostatic latent image with a developer containing a toner to form a toner image.

[0125] The developing step is not particularly limited and can be appropriately selected according to a purpose, as long as the developing step is a step of developing the electrostatic latent image with a developer containing a toner to form a toner image. The developing step can be implemented by the developing unit, for example.

[0126] The developing unit may use a dry developing method or a wet developing method. Further, the developing unit may be a monochrome developing unit or a multicolor developing unit. The developing unit is preferably a developing device including a stirring device that frictionally stirs the toner to charge the toner, and a rotatable developer bearer including amagnetic field generating unit fixed on the inside and carrying a developer including the toner on a surface.For example, in the developing unit, the toner and the carrier are mixed and stirred, and at this time, the toner is charged by friction, and is maintained in an upright state on the surface of a rotating magnet roller, to form a magnetic brush. The magnet roller is arranged in the vicinity of the electrostatic latent image bearer. Therefore, a part of the toner forming the magnetic brush formed on the surface of the magnet roller moves to the surface of the electrostatic latent image bearer by electric attraction. As a result, the electrostatic latent image is developed by the toner, and a visible image is formed by the toner on the surface of the electrostatic latent image bearer.

[0127] <Transfer Unit and Transfer Step>The transfer unit is not particularly limited and can be appropriately selected according to a purpose, as long as the transfer unit is a unit used for transferring the toner image onto a peelable support body or a flexible recording medium having a surface roughness of 1 pm or more. However, in a preferred aspect, the transfer unit includes a primary transfer unit that transfers the toner image onto an intermediate transfer body to form a composite transfer image, and a secondary transfer unit that transfers the composite transfer image onto the peelable support body or the flexible recording medium.

[0128] The transfer step is not particularly limited and can be appropriately selected according to a purpose, as long as the transfer step is a step of transferring the toner image onto a peelable support body or a flexible recording medium having a surface roughness of 1 pm or more. However, in a preferred aspect, an intermediate transfer body is used to primarily transfer the toner image onto the intermediate transfer body to form a composite transfer image, and then, the composite transfer image is secondarily transferred onto the peelable support body or the flexible recording medium. The transfer step can be implemented by the transfer unit, for example.

[0129] Here, when an image to be secondarily transferred onto the peelable support body or the flexible recording medium is a color image including toners of a plurality of colors, a configuration may be such that the transfer unit sequentially superimposes toners of each color on the intermediate transfer body to form an image on the intermediate transfer body, and the intermediate transfer unit secondarily transfers the image on the intermediate transfer body onto the peelable support body or the flexible recording medium in one process.

[0130] The intermediate transfer body is not particularly limited and can be appropriately selected from known transfer bodies according to a purpose. Preferred examples of the intermediate transfer body include, but are not limited to, a transfer belt.

[0131] The transfer unit (including the primary transfer unit and the secondary transfer unit) preferably includes at least a transfer device that peels and charges the toner image formed on the photoconductor toward the peelable support body or the flexible recording medium. Examples of the transfer device include, but are not limited to, a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.

[0132] <Fixing Unit and Fixing Step>The fixing unit is not particularly limited and can be appropriately selected according to a purpose, as long as the fixing unit is a unit used for fixing the toner image transferred onto the peelable support body or the flexible recording medium. Preferably, the fixing unit is formed by a known heating and pressing member. Examples of the heating and pressing member include, but are not limited to, a combination of a heating roller and a pressure roller, and a combination of a heating roller, a pressure roller, and an endless belt.

[0133] The fixing step is not particularly limited and can be appropriately selected according to a purpose, as long as the fixing step is a step of fixing the toner image transferred onto the peelable support body or the flexible recording medium. The fixing step may be performed every time toner of each color is transferred onto the peelable support body or the flexible recording medium, or simultaneously at once after the toners of each color are superimposed. The fixing step can be implemented by the fixing unit, for example.

[0134] Normally, the heating temperature in the heating and pressing member is preferably from 80°C to 200°C.

[0135] Note that, in the present embodiment, according to a purpose, a known optical fixing device may be used together with or instead of the fixing unit, for example.

[0136] The surface pressure in the fixing step is not particularly limited and can be appropriately selected according to a purpose, but is preferably from 10 N / cm2to 80 N / cm2.

[0137] <Other Units and Other Steps>Examples of the other units include, but are not limited to, a cleaning unit, a static elimination unit, a recycling unit, and a control unit.Examples of the other steps include, but are not limited to, a cleaning step, a static elimination step, a recycling step, and a control step.

[0138] - Cleaning Unit and Cleaning Step -The cleaning unit is not particularly limited and can be appropriately selected according to a purpose, as long as the cleaning unit is a unit that can remove the toner remaining on thephotoconductor. Examples of the cleaning unit include, but are not limited to, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, a brush cleaner, and a web cleaner.

[0139] The cleaning step is not particularly limited and can be appropriately selected according to a purpose, as long as the cleaning step is a step by which it is possible to remove the toner remaining on the photoconductor. For example, the cleaning step may be performed by the cleaning unit.

[0140] - Static Elimination Unit and Static Elimination Step -The static elimination unit is not particularly limited and may be appropriately selected according to a purpose, as long as the static elimination unit is a unit that applies a static elimination bias to the photoconductor to discharge the photoconductor. Examples of the static elimination unit include, but are not limited to, a static elimination lamp.

[0141] The static elimination step is not particularly limited and may be appropriately selected according to a purpose, as long as the static elimination step is a step of applying a static elimination bias to the photoconductor to discharge the photoconductor. For example, the static elimination step may be performed by the static elimination unit.

[0142] - Recycling Unit and Recycling Step -The recycling unit is not particularly limited and may be appropriately selected according to a purpose, as long as the recycling unit is a unit causing the developing device to recycle the toner removed in the cleaning step. Examples of the recycling unit include, but are not limited to, a known conveyance unit.

[0143] The recycling step is not particularly limited and may be appropriately selected according to a purpose, as long as the recycling step is a step of causing the developing device to recycle the toner removed in the cleaning step. For example, the recycling step may be performed by the recycling unit.

[0144] - Control Unit and Control Step -The control unit is not particularly limited and can be appropriately selected according to a purpose, as long as the control unit is a unit that can control the operation of each of the unit described above. Examples of the control unit include, but are not limited to, equipment such as a sequencer and a computer.

[0145] The control step is not particularly limited and can be appropriately selected according to a purpose, as long as the control step is a step by which it is possible to control an operation of each step. For example, the control step can be performed by the control unit.

[0146] Next, referring to FIG. 1, one aspect of implementing a method of forming an image on a peelable support body by the image forming apparatus of the present embodiment to obtain an image transfer sheet is described. An image forming apparatus 100A illustrated in FIG. 1 includes a photoconductor drum 10 (may be referred to as “photoconductor 10” hereinafter) as the electrostatic latent image bearer, a charging roller 20 as the charging unit, an exposure device 30 as the exposure unit, a developing device 40 as the developing unit, an intermediate transfer body 50, a cleaning device 60 as the cleaning unit including a cleaning blade, and a static elimination lamp 70 as the static elimination unit.

[0147] The intermediate transfer body 50 is an endless belt, and is designed to be movable in the direction of an arrow by three rollers 51 that are arranged inside the intermediate transfer body 50 and stretch the intermediate transfer body 50. A part of the three rollers 51 also function as transfer bias rollers that can apply a predetermined transfer bias (a primary transfer bias) to the intermediate transfer body 50. A cleaning device 90 including a cleaning blade is arranged in the vicinity of the intermediate transfer body 50. Further, a transfer roller 80 serving as the transfer unit that can apply a transfer bias for transferring (secondarily transferring) the developed image (the toner image) to a peelable support body 95 is arranged in the vicinity of the intermediate transfer body 50, facing the intermediate transfer body 50. A corona charging device 58 for applying an electric charge to the toner image on the intermediate transfer body 50 is arranged in the periphery of the intermediate transfer body 50, between a contact portion between the photoconductor 10 and the intermediate transfer body 50 and a contact portion between the intermediate transfer body 50 and the peelable support body 95, in the direction of rotation of the intermediate transfer body 50.

[0148] The developing device 40 includes a developing belt 41 as the developer bearer, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C arranged in the periphery of the developing belt 41. The black developing unit 45K includes a developer storage portion 42K, a developer supply roller 43K, and a developing roller 44K. The yellow developing unit 45Y includes a developer storage portion 42Y, a developer supply roller 43Y, and a developing roller 44Y. The magenta developing unit 45M includes a developer storage portion 42M, a developer supply roller 43M, and a developing roller 44M. The cyan developing unit 45C includes a developer storage portion 42C, a developer supply roller 43C, and a developing roller 44C. The developing belt 41 is an endless belt that is rotatably stretched over a plurality of belt rollers and a part of the developing belt 41 contacts the electrostatic latent image bearer 10.

[0149] In the image forming apparatus 100A illustrated in FIG. 1, for example, the charging roller 20 uniformly charges the photoconductor drum 10. The exposure device 30 emits light to the photoconductor drum 10 so as to form an electrostatic latent image. The electrostatic latentimage formed on the photoconductor drum 10 is developed with toner supplied from the developing device 40 to form a toner image. The toner image is transferred (primarily transferred) onto the intermediate transfer body 50 by a voltage applied from the rollers 51, and is further transferred (secondarily transferred) onto the peelable support body 95. As a result, a transferred image is formed on the peelable support body 95, and an image transfer sheet is obtained. Note that toner remaining on the photoconductor 10 is removed by the cleaning device 60, and the charge of the photoconductor 10 is temporarily removed by the static elimination lamp 70.

[0150] FIG. 2 is a diagram illustrating another example of the image forming apparatus of the present embodiment. An image forming apparatus 100B has a similar configuration to the image forming apparatus 100A illustrated in FIG. 1, except that the developing belt 41 is not provided and the black developing unit 45K, the yellow developing unit 45Y, the magenta developing unit 45M, and the cyan developing unit 45C are arranged in the periphery of the photoconductor drum 10, directly facing the photoconductor drum 10.

[0151] FIG. 3 is a diagram illustrating another example of the image forming apparatus of the present embodiment. The image forming apparatus illustrated in FIG. 3 includes a copying device main body 150, a sheet feeding table 200, a scanner 300, and an automatic document feeder (ADF) 400.

[0152] The intermediate transfer body 50 that is formed as an endless belt is provided in a center portion of the copying device main body 150.The intermediate transfer body 50 is stretched over support rollers 14, 15, and 16 and is rotatable clockwise in FIG. 3. An intermediate transfer body cleaning device 17 for removing toner remaining on the intermediate transfer body 50 is arranged in the vicinity of the support roller 15. A tandem developing device 120 in which four image forming units 18 for yellow, cyan, magenta, and black are arranged side by side along the conveyance direction of the intermediate transfer body 50, is arranged facing the intermediate transfer body 50 that is stretched by the support roller 14 and the support roller 15. An exposure device 21 serving as the exposure member, is arranged in the vicinity of the tandem developing device 120. A secondary transfer device 22 is arranged on the side of the intermediate transfer body 50 opposite to the side on which the tandem developing device 120 is arranged. In the secondary transfer device 22, a secondary transfer belt 24, which is formed as an endless belt, is stretched over a pair of rollers 23, and a transfer sheet conveyed on the secondary transfer belt 24 can contact the intermediate transfer body 50. A fixing device 25 serving as the fixing unit is arranged in the vicinity of the secondary transfer device 22. The fixing device 25 includes a fixing belt 26, which is formed as an endless belt, and a pressure roller 27 arranged to be pressed against the fixing belt 26.

[0153] Note that, in the tandem image forming apparatus, a sheet reversing device 28 is arranged in the vicinity of the secondary transfer device 22 and the fixing device 25 for reversing the transfer sheet to form an image on both sides of the transfer sheet.

[0154] Next, the formation of a full-color image (color copy) by using the tandem developing device 120 will be described. That is, first, a document is set on a document platen 130 of the automatic document feeder (ADF) 400. Alternatively, the automatic document feeder 400 is opened, the document is set on a contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed.

[0155] When a start switch is pressed, if the document is set on the automatic document feeder 400, the document is conveyed and moved onto the contact glass 32 and then, the scanner 300 is driven. On the other hand, if the document is set on the contact glass 32, the scanner 300 is driven immediately. Subsequently, a first traveling body 33 and a second traveling body 34 start traveling. At this time, light from the light source is emitted by the first traveling body 33, and reflected light from the surface of the document is reflected by a mirror in the second traveling body 34, and is received by a reading sensor 36 via an image forming lens 35. Thus, the color document (color image) is read, and image information of black, yellow, magenta, and cyan images is obtained.

[0156] Subsequently, the pieces of image information of black, yellow, magenta, and cyan images are each transmitted to the image forming units 18 (black image forming unit, yellow image forming unit, magenta image forming unit, and cyan image forming unit) in the tandem developing device 120. Next, in each image forming unit, a black toner image, a yellow toner image, a magenta toner image, or a cyan toner image is formed. That is, as illustrated in FIG. 4, each of the image forming units 18 (the black image forming unit, the yellow image forming unit, the magenta image forming unit, and the cyan image forming unit) in the tandem developing device 120 includes the electrostatic latent image bearer 10 (a black electrostatic latent image bearer 10K, a yellow electrostatic latent image bearer 10Y, a magenta electrostatic latent image bearer 10M, and a cyan electrostatic latent image bearer 10C), a charging device 160 serving as the charging unit and uniformly charging the electrostatic latent image bearer 10, an exposure device that emits light (L in FIG. 4), based on the image information of each color, to the electrostatic latent image bearer , to form an electrostatic latent image corresponding to each color image on the electrostatic latent image bearer, a developing device 61 serving as the developing unit that develops the electrostatic latent image with toner of each color (black toner, yellow toner, magenta toner, and cyan toner) to form a toner image with each color toner, a transfer charging device 62 that transfers the toner image onto the intermediate transfer body 50, a cleaning device 63, and a static elimination device 64. Each image forming unit 18 can form a monochrome image (a black image, a yellow image, a magenta image, or a cyan image), based on the image information ofeach color. The black image, the yellow image, the magenta image, and the cyan image formed as described above, that is, the black image formed on the black electrostatic latent image bearer 10K, the yellow image formed on the yellow electrostatic latent image bearer 10Y, the magenta image formed on the magenta electrostatic latent image bearer 10M, and the cyan image formed on the cyan electrostatic latent image bearer IOC, are sequentially transferred (primarily transferred) onto the intermediate transfer body 50 which is rotatably moved by the support rollers 14, 15, and 16. The black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer body 50 to form a composite color image (a transferred color image).

[0157] On the other hand, in the sheet feeding table 200, one of sheet feeding rollers 142 is selectively rotated to feed a sheet (a peelable support body) from one of paper feed cassettes 144 provided in several stages in a paper bank 143. The sheets are separated one by one by the separation rollers 145 and fed to a sheet feeding path 146, conveyed by conveyance rollers 147 and guided to a sheet feeding path 148 inside the copying device main body 150, where the sheets abut against and are stopped by registration rollers 49. Alternatively, the sheet feeding rollers 142 are rotated to feed sheets (recording paper) from a manual feed tray 54. The sheets are separated one by one by separation rollers 52 and fed into a manual feed path 53, and similarly abut against and are stopped by the registration rollers 49. The registration rollers 49 are generally grounded to be used, but may be used with a bias applied thereto to remove paper dust from the sheet. The registration rollers 49 are rotated at a timing adjusted with the composite color image (transferred color image) synthesized on the intermediate transfer body 50, and a sheet (peelable support body) is fed between the intermediate transfer body 50 and the secondary transfer device 22, to transfer (secondarily transfer) the composite color image (color transfer image) onto the sheet (peelable support body) by the secondary transfer device 22. Thus, the color image is transferred onto and formed on the sheet (peelable support body). After the image is transferred, toner remaining on the intermediate transfer body 50 is cleaned by the intermediate transfer body cleaning device 17.

[0158] The sheet (peelable support body) onto which the color image is transferred and on which the color image is formed, is conveyed by the secondary transfer device 22 and fed to the fixing device 25. In the fixing device 25, the composite color image (transferred color image) is fixed onto the sheet (peelable support body) by heat and pressure. Subsequently, a switching claw 55 switches the sheet (peelable support body) to discharge the sheet by discharge rollers 56 and the sheets are stacked on a sheet discharge tray 57. Alternatively, the sheet (peelable support body) is switched by the switching claw 55, reversed by the sheet reversing device 28, and guided again to the transfer position. After an image is recorded on the back side of the sheet, the sheet is discharged by the discharge rollers 56 and the sheets are stacked on the sheet discharge tray 57. As described above, an image transfer sheet is obtained.

[0159] (Process Cartridge)The process cartridge according to the present embodiment is molded to be attachable to and detachable from various types of image forming apparatuses, and includes at least an electrostatic latent image bearer that carries an electrostatic latent image, and a developing unit that develops the electrostatic latent image carried on the electrostatic latent image bearer with the developer of the present embodiment to form a toner image. The process cartridge of the present embodiment may further include other units, if desired.

[0160] The developing unit includes at least a developer storage container that stores the developer of the present embodiment, and a developer bearer that carries and conveys the developer stored in the developer storage container. The developing unit may further include a regulating member that regulates the thickness of the developer carried on the developing unit.

[0161] FIG. 5 is a diagram illustrating a process cartridge according to the present embodiment. A process cartridge 110 includes a photoconductor drum 10, a corona charging device 58, a developing device 40, a transfer roller 80, and a cleaning device 90.[Examples]

[0162] Examples of the present embodiment will be described below, but the present invention is not limited to the following examples in any way. The term “parts” refers to “parts by mass”, unless otherwise specified. “%” refers to “mass%”, unless otherwise specified.

[0163] The measurement values in the examples described below were obtained by the methods described herein. The Tg and the molecular weight of the polyester resin A having the structure (A), the other polyester resin, the crystalline polyester resin, and the like were measured from each of the resins obtained in the Manufacturing Examples.

[0164] (Manufacturing Example 1)<Synthesis of Ketimine>170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were filled into a reaction vessel equipped with a stirring rod and a thermometer, and the mixture was reacted at 50°C for 5 hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 418.

[0165] (Manufacturing Example A-l)<Synthesis of Polyester Resin A-l>- Synthesis of Prepolymer A-l -A reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. 3- methyl-l,5-pentanediol, terephthalic acid, and adipic acid were filled into the reaction vessel together with titanium tetraisopropoxide (1,000 ppm with respect to the resin components), sothat the molar ratio of hydroxyl groups to carboxyl groups OH / COOH was 1.2, the configuration of the diol component was 100 mol% of 3 -methyl- 1,5-pentanediol, and the configuration of the dicarboxylic acid component was 50 mol% of terephthalic acid and 50 mol% of adipic acid.Subsequently, the temperature was raised to 200°C over about 4 hours, and then, raised to 230°C over 2 hours, and the reaction was continued until no water was discharged.Afterwards, the mixture was further reacted for 5 hours under a reduced pressure of 10 mmHg to 15 mmHg to obtain an intermediate polyester A'-l.The obtained intermediate polyester A'-l had a Tg of -40°C, an Mw of 15,000, and an Mw / Mn of 2.0.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester A'- 1 and isophorone diisocyanate (IPDI) were filled into the reaction vessel in a molar ratio (isocyanate groups of IPDI / hydroxyl groups of intermediate polyester) of 1.5, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of intermediate polyester A-l.The obtained intermediate polyester A-l had a Tg of -35°C, an Mw of 20,000, and an Mw / Mn of 2.2.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester A-l and lysine triisocyanate (LTI) were filled into the reaction vessel in a molar ratio (isocyanate groups of LTI / isocyanate groups of intermediate polyester) of 0.2, and the mixture was diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, pure water was added dropwise in an amount to obtain a molar ratio of 0.5 relative to the amount of isocyanate present in the reaction system. Afterwards, the mixture was reacted at 100°C for 5 hours to obtain a solution of prepolymer A-l.

[0166] - Synthesis of Polyester Resin A-l -The obtained prepolymer A-l was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen inlet tube. Further, [ketimine compound 1] was added drop wise to the reaction vessel in an amount so that the amount of amine of [ketimine compound 1] was equimolar to the amount of isocyanate in the prepolymer A-l. After stirring at 45°C for 10 hours, a prepolymer extension product was extracted.The obtained prepolymer extension product was dried under reduced pressure at 50°C until the amount of residual ethyl acetate was 100 ppm or less, to obtain an amorphous polyester resin A-l. Note that polyester resin A-l has a structure corresponding to Structural Formula 1) of Structure (A).

[0167] (Manufacturing Example A-2)<Synthesis of Polyester Resin A-2>- Synthesis of Prepolymer A-2 -A reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. 3- methyl-l,5-pentanediol, terephthalic acid, and adipic acid were filled into the reaction vessel together with titanium tetraisopropoxide (1,000 ppm with respect to the resin components), so that the molar ratio of hydroxyl groups to carboxyl groups OH / COOH was 1.18, the configuration of the diol component was 100 mol% of 3 -methyl- 1,5-pentanediol, and the configuration of the dicarboxylic acid component was 40 mol% of terephthalic acid and 60 mol% of adipic acid.Subsequently, the temperature was raised to 200°C over about 4 hours, and then, raised to 230°C over 2 hours, and the reaction was continued until no water was discharged.Afterwards, the mixture was further reacted for 6 hours under a reduced pressure of 10 mmHg to 15 mmHg to obtain an intermediate polyester A'-2.The obtained intermediate polyester A'-2 had a Tg of -53 °C, an Mw of 15,000, and an Mw / Mn of 2.0.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester A'-2 and an isocyanurate-type triisocyanate derived from hexamethylene diisocyanate (BURNOCK DN-901S, manufactured by DIC Corporation) were added to the reaction vessel in a molar ratio (isocyanate groups of DN-901S / hydroxyl groups of intermediate polyester) of 0.4, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of intermediate polyester A-2. The obtained intermediate polyester A-2 had a Tg of -43 °C, an Mw of 24,000, and an Mw / Mn of 2.4.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The solution of intermediate polyester A-2 and isophorone diisocyanate (IPDI) were filled into the reaction vessel in a molar ratio (isocyanate groups of IPDI / hydroxyl groups of intermediate polyester) of 1.5, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of prepolymer A-2.

[0168] - Synthesis of Polyester Resin A-2 -The obtained prepolymer A-2 was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen inlet tube. Further, [ketimine compound 1] was added drop wise to the reaction vessel in an amount so that the amount of amine of [ketimine compound 1] was equimolar to the amount of isocyanate in the prepolymer A-2. After stirring at 45°C for 10 hours, a prepolymer extension product was extracted.The obtained prepolymer extension product was dried under reduced pressure at 50°C until the amount of residual ethyl acetate was 100 ppm or less, to obtain an amorphous polyester resin A-2. Note that polyester resin A-2 has a structure corresponding to Structural Formula 2) of Structure (A).

[0169] (Manufacturing Example A-3)<Synthesis of Polyester Resin A-3>- Synthesis of Prepolymer A- 3 -A reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. 3- methyl-l,5-pentanediol, terephthalic acid, and adipic acid were filled into the reaction vessel together with titanium tetraisopropoxide (1,000 ppm with respect to the resin components), so that the molar ratio of hydroxyl groups to carboxyl groups OH / COOH was 1.2, the configuration of the diol component was 100 mol% of 3 -methyl- 1,5-pentanediol, and the configuration of the dicarboxylic acid component was 50 mol% of terephthalic acid and 50 mol% of adipic acid.Subsequently, the temperature was raised to 200°C over about 4 hours, and then, raised to 230°C over 2 hours, and the reaction was continued until no water was discharged.Afterwards, the mixture was further reacted for 5 hours under a reduced pressure of 10 mmHg to 15 mmHg to obtain an intermediate polyester A-3.The obtained intermediate polyester A-3 had a Tg of -40°C, an Mw of 15,000, and an Mw / Mn of 2.0.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester A-3 and isophorone diisocyanate (IPDI) were filled into the reaction vessel in a molar ratio (isocyanate groups of IPDI / hydroxyl groups of intermediate polyester) of 1.5, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of intermediate polyester A-3.Subsequently, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester solution A-3 and trimethylolpropane (TMP) were filled into the reaction vessel in a molar ratio (isocyanate groups of intermediate polyester A- 3 / hydroxyl groups of TMP) of 5.0, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Afterwards, the solution was reacted at 100°C for 5 hours to obtain prepolymer A-3.

[0170] - Synthesis of Polyester Resin A-3 -The obtained prepolymer A-3 was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen inlet tube. Further, [ketimine compound 1] was added drop wise to the reaction vessel in an amount so that the amount of amine of [ketimine compound 1] was equimolar to the amount of isocyanate in the prepolymer A-3. After stirring at 45 °C for 10 hours, a prepolymer extension product was extracted.The obtained prepolymer extension product was dried under reduced pressure at 50°C until the amount of residual ethyl acetate was 100 ppm or less, to obtain an amorphous polyester resin A-3. Note that polyester resin A-3 has a structure corresponding to Structural Formula 3) of Structure (A).

[0171] (Manufacturing Example A-4)<Synthesis of Polyester Resin A-4>- Synthesis of Prepolymer A-4 -A reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. 3- methyl-l,5-pentanediol, terephthalic acid, and adipic acid were filled into the reaction vessel together with titanium tetraisopropoxide (1,000 ppm with respect to the resin components), so that the molar ratio of hydroxyl groups to carboxyl groups OH / COOH was 1.2, the configuration of the diol component was 100 mol% of 3 -methyl- 1,5-pentanediol, and the configuration of the dicarboxylic acid component was 50 mol% of terephthalic acid and 50 mol% of adipic acid.Subsequently, the temperature was raised to 200°C over about 4 hours, and then, raised to 230°C over 2 hours, and the reaction was continued until no water was discharged. Afterwards, the mixture was further reacted for 5 hours under a reduced pressure of 10 mmHg to 15 mmHg to obtain an intermediate polyester A'-4.The obtained intermediate polyester A'-4 had a Tg of -40°C, an Mw of 15,000, and an Mw / Mn of 2.0.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The intermediate polyester A'-4 and isophorone diisocyanate (IPDI) were filled into the reaction vessel in a molar ratio (isocyanate groups of IPDI / hydroxyl groups of intermediate polyester) of 0.2, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of intermediate polyester A-4.The obtained intermediate polyester A-4 had a Tg of -34°C, an Mw of 17,000, and an Mw / Mn of 2.2.Next, a reaction vessel was equipped with a cooling tube, a stirrer, and a nitrogen inlet tube. The solution of intermediate polyester A-4 and isophorone diisocyanate (IPDI) were filled into the reaction vessel in a molar ratio (isocyanate groups of IPDI / hydroxyl groups of intermediate polyester) of 1.5, and diluted with ethyl acetate to obtain a 50% ethyl acetate solution. Subsequently, the solution was reacted at 100°C for 5 hours to obtain a solution of prepolymer A-4.

[0172] - Synthesis of Polyester Resin A-4 -The obtained prepolymer A-4 was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen inlet tube. Further, [ketimine compound 1] was added drop wise to the reaction vessel in an amount so that the amount of amine of [ketimine compound 1] was equimolar to the amount of isocyanate in the prepolymer A-4. After stirring at 45°C for 10 hours, a prepolymer extension product was extracted.The obtained prepolymer extension product was dried under reduced pressure at 50°C until the amount of residual ethyl acetate was 100 ppm or less, to obtain an amorphous polyester resin A-4. Note that polyester resin A-4 does not corresponding to any of Structural Formulas 1) to 3) of Structure (A).

[0173] (Manufacturing Example B-l)<Synthesis of Polyester Resin B-l>A four-neck flask was equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple. 1,2-propylene glycol, terephthalic acid, and adipic acid were filled into the flask, so that the molar ratio was 120 / 98 / 2. The mixture was heated in a nitrogen atmosphere. Next, 0.05 g of dibutyltin oxide was added, and the mixture was reacted while maintaining the temperature at 200°C to obtain polyester resin B-l. The resin B-l had a Tg of 60°C and an Mw of 12,000.

[0174] (Manufacturing Example C-l)<Synthesis of Crystalline Polyester Resin C-l>A 5 L four-neck flask was equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple. Dodecanedioic acid and 1,6-hexanediol were filled into the flask, so that the molar ratio of hydroxyl groups to carboxyl groups OH / COOH was 0.9, and reacted together with titanium tetraisopropoxide (500 ppm with respect to the resin components) at 180°C for 10 hours. Subsequently, the temperature was raised to 200°C and the mixture was reacted for 3 hours, and then, further reacted at a pressure of 8.3 kPa for 2 hours to obtain crystalline polyester resin C-l.

[0175] (Example 1)Preparation of Masterbatch (MB)>1,200 parts of water, 500 parts of an organic white pigment (HAKKOL OWP, manufactured by Showa Kagaku Kogyo Co., Ltd.), and 500 parts of the polyester resin B-l were added and mixed in a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). The mixture was kneaded by using two rolls at 150°C for 30 minutes, and then, rolled to cool and pulverized in a pulverizer to obtain [masterbatch 1].

[0176] Preparation of WAX Dispersion Liquid>A container was equipped with a stirring rod and a thermometer. 50 parts of paraffin wax (manufactured by Nippon Seiro Co., Ltd., HNP-9, a hydrocarbon wax, melting point of 75°C, SP value of 8.8) as release agent 1 and 450 parts of ethyl acetate were filled into the container. The temperature was raised to 80°C while stirring, and the mixture was kept at 80°C for 5 hours, and then, cooled to 30°C during 1 hour. The mixture was dispersed by using a bead mill (ULTRA VISCOMILL, manufactured by Aimex Co., Ltd.) under conditions including a liquid delivery rate of 1 kg / hr, a disk peripheral speed of 6 m / sec, addition of 80 vol% of zirconia beads having a diameter of 0.5 mm, and 3 repetitions to obtain [WAX dispersion liquid 1].

[0177] Preparation of Crystalline Polyester Resin Dispersion Liquid>A container was equipped with a stirring rod and a thermometer. 50 parts of crystalline polyester resin C-l and 450 parts of ethyl acetate were filled into the container. The temperature was raised to 80°C while stirring, and the mixture was kept at 80°C for 5 hours, and then, cooled to 30°C during 1 hour. The mixture was dispersed by using a bead mill (ULTRA VISCOMILL, manufactured by Aimex Co., Ltd.) under conditions including a liquid delivery rate of 1 kg / hr, a disk peripheral speed of 6 m / sec, addition of 80 vol% of zirconia beads having a diameter of 0.5 mm, and 3 repetitions to obtain [crystalline polyester resin dispersion liquid 1].

[0178] Preparation of Oil Phase>500 parts of [WAX dispersion liquid 1], 800 parts of [prepolymer A-l], 500 parts of [crystalline polyester resin dispersion liquid 1], 450 parts of [polyester resin B-l], 100 parts of [masterbatch 1], and 2 parts of [ketimine compound 1] as a curing agent were filled into a container and mixed by using a TK HOMO MIXER (manufactured by Tokushu Kika Co., Ltd.) at 5,000 rpm for 60 minutes to obtain [oil phase 1].

[0179] <Synthesis of Organic Fine Particle Emulsion (Fine Particle Dispersion Liquid)> A reaction vessel was equipped with a stirring rod and a thermometer. 683 parts of water, 11 parts of a sodium salt of methacrylic acid ethylene oxide adduct sulfate ester (ELEMINOL RS-30: manufactured by Sanyo Chemical Industries, Ltd.), 138 parts of styrene, 138 parts of methacrylic acid, and 1 part of ammonium persulfate were filled into the reaction vessel, and the mixture was stirred at 400 rpm for 15 minutes, to obtain a white emulsion. The system was heated to an internal temperature of 75°C, and the mixture was reacted for 5 hours. Further, 30 parts of a 1% aqueous solution of ammonium persulfate was added, and the mixture was let to mature at 75 °C for 5 hours to obtain [fine particle dispersion liquid 1], which is an aqueous dispersion liquid of a vinyl resin (a copolymer of styrene-methacrylic acid and a sodium salt of methacrylic acid ethylene oxide adduct sulfate ester).The volume average particle diameter of [fine particle dispersion liquid 1] was measured by using an LA-920 (manufactured by HORIBA Corporation) and was found to be 0.14 pm. A part of [fine particle dispersion liquid 1] was dried to isolate the resin content.

[0180] Preparation of Aqueous Phase> 990 parts of water, 83 parts of the [fine particle dispersion liquid 1], 37 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (ELEMINOL MON-7: manufactured by Sanyo Chemical Industries, Ltd.), and 90 parts of ethyl acetate were mixed and stirred to obtain a milky white liquid. The obtained liquid was defined as [aqueous phase 1].

[0181] Pmulsification and Solvent Removal >1,200 parts of [aqueous phase 1] was added to the container containing the [oil phase 1] and the mixture was mixed by using a TK HOMO MIXER at a rotation speed of 13,000 rpm for 20 minutes to obtain [emulsified slurry 1].The [emulsified slurry 1] was placed in a container equipped with a stirrer and a thermometer. Subsequently, the solvent was removed at 30°C for 8 hours, and then, the obtained product was let to mature at 45°C for 4 hours to obtain [dispersed slurry 1].

[0182] < Washing and Drying >100 parts of [dispersed slurry 1] was filtered under reduced pressure to obtain a filter cake, and then, the following operations were performed.(1): 100 parts of ion-exchanged water was added to the filter cake, the mixture was mixed by using a TK HOMO MIXER (at a rotation speed of 12,000 rpm for 10 minutes), and then, the mixture was filtered.(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake obtained in (1), and the mixture was mixed by using a TK HOMO MIXER (at a rotation speed of 12,000 rpm for 30 minutes), and then, the mixture was filtered under reduced pressure.(3): 100 parts of 10% hydrochloric acid was added to the filter cake obtained in (2), and the mixture was mixed by using a TK HOMO MIXER (at a rotation speed of 12,000 rpm for 10 minutes) and then, the mixture was filtered.(4): 300 parts of ion-exchanged water was added to the filter cake obtained in (3), the mixture was mixed by using a TK HOMO MIXER (at a rotation speed of 12,000 rpm for 10 minutes), and then, the mixture was filtered. The above-described operations (1) to (4) were repeated twice to obtain a [filter cake].The [filter cake] was dried in a circulating air dryer at 45°C for 48 hours and sieved through a 75 pm mesh to obtain [toner base particles 1],

[0183] <External Addition Process >0.6 parts by mass of hydrophobic silica having an average particle diameter of 100 nm, 1.0 parts by mass of titanium oxide having an average particle diameter of 20 nm, and 0.8 parts of hydrophobic silica fine powder having an average particle diameter of 15 nm with respect to 100 parts by mass of the toner base particles 1, were mixed in a Henschel mixer to obtain [toner 1].

[0184] (Example 2)[Toner base particles 2] were obtained similarly to Example 1, except that the prepolymer A-l in Example 1 was replaced with prepolymer A-2. The [toner base particles 2] were used to obtain [toner 2].

[0185] (Example 3)[Toner base particles 3] were obtained similarly to Example 1, except that the prepolymer A-l in Example 1 was replaced with prepolymer A-3. The [toner base particles 3] were used to obtain [toner 3].

[0186] (Example 4)[Toner base particles 5] were obtained similarly to Example 1, except that the composition ratio of polyester resin A and polyester resin B in Example 2 was changed as indicated in Table 1. The [toner base particles 5] were used to obtain [toner 5].

[0187] (Example 5)[Toner base particles 6] were obtained similarly to Example 1, except that the composition ratio of polyester resin A and polyester resin B in Example 2 was changed as indicated in Table 1. The [toner base particles 6] were used to obtain [toner 6].

[0188] (Comparative Example 1)[Toner base particles 4] were obtained similarly to Example 1, except that the prepolymer A-l in Example 1 was replaced with prepolymer A-4. The [toner base particles 4] were used to obtain [toner 4].

[0189] (Comparative Example 2)[Toner base particles 7] were obtained similarly to Example 1, except that the composition ratio of polyester resin A and polyester resin B in Example 2 was changed as indicated in Table 1. The [toner base particles 7] were used to obtain [toner 7].

[0190] (Comparative Example 3)[Toner base particles 8] were obtained similarly to Example 1, except that the composition ratio of polyester resin A and polyester resin B in Example 2 was changed as indicated in Table 1. The [toner base particles 8] were used to obtain [toner 8].

[0191] Preparation of Carrier>100 parts by mass of a silicone resin (Organo Straight Silicone), 5 parts by mass of y-(2- aminoethyl)aminopropyltrimethoxysilane, and 10 parts by mass of carbon black were added to 100 parts by mass of toluene, and the mixture was dispersed for 20 minutes by using a homomixer to prepare a resin layer coating liquid. A fluidized bed-type coating device was used to apply the resin layer coating liquid to the surface of 1,000 parts by mass of spherical magnetite having an average particle diameter of 50 pm to prepare a carrier.

[0192] Preparation of Developed5 parts by mass of the toner of each of the Examples and Comparative Examples and 95 parts by mass of the carrier were mixed in a ball mill to prepare a developer.

[0193] Preparation of Evaluation Images>(1) A developer using the toner of each of the Examples and Comparative Examples was set at the fifth station of a RICOH Pro C7200S (manufactured by Ricoh Co., Ltd.), and the development and transfer conditions were adjusted by using a process controller so that the toner adhesion amount was 1.0 mg / cm2. A solid toner image was output in an image layer formation area on a release paper (product name: WOW LIGHT 8.0, manufactured by Piotec Co., Ltd.).(2) Next, the toner image transferred to the release paper was fixed.(3) A 100% polyester cloth was superimposed on the toner image on the release paper, and an iron having a temperature of 160°C was applied to the fabric with a load of 600 g / cm2for 10 seconds to thermally transfer the toner image to the cloth, and thus prepare an image for evaluation.

[0194] In each of the Examples and Comparative Examples, various characteristics were evaluated as follows.

[0195] < Analysis of THF-Insoluble Organic Matter>One part of toner was added to 40 parts of THF and the mixture was refluxed for 6 hours. Subsequently, insoluble components were precipitated by using a centrifuge to separate the insoluble components and the supernatant. The insoluble components were dried at 40°C for 20 hours to obtain THF-insoluble organic matter. The content of the THF-insoluble organic matter was calculated from the weight of the THF-insoluble organic matter.

[0196] < Analysis of Miscibility >The cross section of the toner particles of each toner was determined by observing a reflected electron image with a scanning electron microscope (SEM). Polyester and urethane have different colors, and thus, it is possible to determine whether sea portions and island portions (immiscible domains) are present. To provide contrast and to facilitate the distinction between the island portions and the sea portions, staining with ruthenium tetroxide (substance name: ruthenium tetroxide, manufactured by TAAB) was performed, if desired. For each of crushed products of molten and kneaded toner components obtained after ruthenium staining, SEM images of the particle cross sections of the crushed products of the molten and kneaded toner components at a position approximately halfway through each particle diameter were captured under the following conditions to determine whether a sea-island structure was present.The procedure is described below.The particles of each toner were embedded in an epoxy resin and observed under the following conditions by using a scanning electron microscope (SU8230, manufactured byHitachi, Ltd.). At this time, the unstained areas are observed as dark portions, and thus, can be distinguished from the stained areas (light portions).- Acceleration voltage: 5 kV- Emission current: 10 pA- Probe current: Norm- Condenser lens 1: 5.0- W.D.: 8.0 mm- Observation mode: SEMagnification: x 2,000 or x 5,000[Evaluation Criteria]Good: No sea-island structurePoor: Sea-island structure present

[0197] <Method of Evaluating Heat-resistant Storage Stability >The toner was allowed to stand in a high-temperature high-humidity chamber at a temperature of 55°C and a humidity of 50% for 24 hours. After the toner stood for 24 hours, the extent of toner blocking was visually observed, and the heat-resistant storage stability was evaluated according to the following criteria. The results are illustrated in Table 1.[Evaluation Criteria]Excellent: No toner clumps are observedGood: Some small clumps of toner that break when lightly pressed are observedMarginal: Clumps of toner that break when lightly pressed are observedPoor: Clumps of toner having a hardness at which clumps do not break when lightly pressed are observed

[0198] <Method of Evaluating Laundering Fastness>The evaluation images obtained with each developer were subjected to a laundering fastness test according to the test method described in JIS 0844:2011 and evaluated according to the following criteria.[Evaluation Criteria]Excellent: Rank 5 on JIS 0844 discoloration gray scale, and no deterioration of image after 10 repetitions of launderingGood: Rank 5 on JIS 0844 discoloration gray scale, and some cracks in image after 10 repetitions of launderingMarginal: Rank 4 or 3 on JIS 0844 discoloration gray scalePoor: Rank 2 or 1 on JIS 0844 discoloration gray scale

[0199] <Method of Evaluating Fixability to Flexible Media>An adhesive tape having a predetermined adhesive strength was applied to the surface of the evaluation image obtained with each developer, and then, the adhesive tape was peeled off to evaluate the state of the remaining evaluation image.[Evaluation Criteria]Excellent: No toner is transferred to the tapeGood: Toner is partly transferred to tape, but not in an outstanding extent, so that no change is noticeable in imageMarginal: Toner is partly transferred to tape, and image is discolored upon closer inspection Poor: Large amount of toner is transferred to tape and image is discolored

[0200] <Method of Evaluating Dryer Durability >The evaluation images obtained with each developer were wetted with water, dried for 90 minutes at 60°C by using a dryer (small household clothing dryer Moco2 ASD-2.5TP, manufactured by ALUMIS), and evaluated according to the following criteria.[Evaluation Criteria]Excellent: No deterioration of ImageGood: Slight roughness is observed in part of image surfaceMarginal: Slight cracks in part of imagePoor: Cracks in entire image

[0201] The evaluation results of each of the Examples and Comparative Examples are illustrated inTable 1.

[0202] [Table 1]In Table 1, the polyester resin A-4 contained in Comparative Example 1 does not correspond to any of Structural Formulas 1) to 3) of Structure (A), and thus, is indicated by “X”.

[0203] Aspects of the present invention include the following, for example.According to a first aspect, a toner includes a polyester resin having a structure (A), and contains 26 wt% or more and less than 70 wt% of THF-insoluble organic matter with respect to 100 wt% of all organic components in the toner.The structure (A) includes R1 having three or more binding sites, and R2 in a number identical to the number of binding sites, in which a bond between each binding site of R1 and each R2 is represented by any one of the structural formulas 1) to 3) below.1) R1-NHCONH-R22) R1-NHCOO-R23) R1-OCONH-R2In the formulas above, R1 represents an aromatic or aliphatic organic group derived from a trihydric or higher alcohol or derived from a trivalent or higher polyisocyanate, and R2 represents a group derived from a polyester polyol.According to a second aspect, in the toner according to the first aspect, the toner further includes a polyester resin not including bisphenol A.According to a third aspect, in the toner according to the second aspect, the polyester resin not including bisphenol A has a weight average molecular weight Mw of 12,000 or more. According to a fourth aspect, in the toner according to any one of the first aspect to the third aspect, the toner has a glass transition temperature of 20°C to 40°C.According to a fifth aspect, in the toner according to any one of the first aspect to the fourth aspect, the toner is achromatic.According to a sixth aspect, in the toner according to any one of the first aspect to the fifth aspect, the toner includes two or more types of resins including the polyester resin having the structure (A), and the polyester resin having the structure (A) is mixed with the rest of the two or more types of resins.According to a seventh aspect, a toner set includes a color toner including a binder resin and a colorant, and the toner according to any one of the first aspect to the sixth aspect.According to an eighth aspect, an image transfer sheet includes a peelable support body and an image on the peelable support body, in which the image is formed with the toner according to any one of the first aspect to the sixth aspect.According to a ninth aspect, a toner storage unit stores the toner according to any one of the first aspect to the sixth aspect.According to a tenth aspect, an image forming apparatus includes an electrostatic latent image bearer, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image bearer, a developing unit that develops the electrostatic latent image with a developer including the toner according to any one of the first aspect to the sixth aspect to form a toner image, a transfer unit that transfers the toner image onto a peelable support body or onto a flexible recording medium having a surface roughness of 1 pm or more, and a fixing unit that fixes the toner image transferred onto the peelable support body or onto the flexible recording medium.According to an eleventh aspect, an image forming method includes forming an electrostatic latent image on an electrostatic latent image bearer, developing the electrostatic latent image with a developer including the toner according to any one of the first aspect to the sixth aspect to form a toner image, transferring the toner image onto a peelable support body or onto a flexible recording medium having a surface roughness of 1 pm or more, and fixing the toner image transferred onto the peelable support body or onto the flexible recording medium. According to a twelfth aspect, in the image forming method according to the eleventh aspect, the toner image is formed as a layer contacting the peelable support body or the flexible recording medium.According to a thirteenth aspect, in the image forming method according to any one of the eleventh aspect and the twelfth aspect, the flexible recording medium includes a fabric including fibers.

[0204] The above-described embodiments are illustrative and do not limit the present invention. Thus, numerous additional modifications and variations are possible in light of the above teachings. For example, elements and / or features of different illustrative embodiments may be combined with each other and / or substituted for each other within the scope of the present invention. Any one of the above-described operations may be performed in various other ways, for example, in an order different from the one described above.

[0205] This patent application is based on and claims priority to Japanese Patent Application Nos. 2023-126512 and 2024-048377, filed on August 2, 2023 and March 25, 2024, in the Japan Patent Office, the entire disclosure of each of which is hereby incorporated by reference herein.[Reference Signs List]

[0206] 10 Electrostatic latent image bearerImage forming unit Peelable support body A Image forming apparatusB Image forming apparatus

Claims

[CLAIMS]

1. A toner comprising: a polyester resin having a structure (A), the structure (A) including R1 having three or more binding sites, and R2 in a number identical to the number of binding sites, in which a bond between each binding site of R1 and each R2 is represented by any one of structural formulas 1) to 3) below;1) R1-NHC0NH-R22) R1-NHC00-R23) R1-0C0NH-R2 where, in the formulas above, R1 represents an aromatic or aliphatic organic group derived from a trihydric or higher alcohol or derived from a trivalent or higher polyisocyanate, and R2 represents a group derived from a polyester polyol, wherein the toner contains 26 wt% or more and less than 70 wt% of THF-insoluble organic matter with respect to 100 wt% of all organic components in the toner.

2. The toner according to claim 1, further comprising a polyester resin not including bisphenolA.

3. The toner according to claim 2, wherein the polyester resin not including bisphenol A has a weight average molecular weight Mw of 12,000 or more.

4. The toner according to any one of claims 1 to 3, wherein the toner has a glass transition temperature of 20°C to 40°C.

5. The toner according to any one of claims 1 to 4, wherein the toner is achromatic.

6. The toner according to any one of claims 1 to 5, wherein the toner comprises two or more types of resins including the polyester resin having the structure (A), and the polyester resin having the structure (A) is mixed with the rest of the two or more types of resins.

7. A toner set comprising: a color toner including a binder resin and a colorant; and the toner according to any one of claims 1 to 6.

8. An image transfer sheet, comprising: a peelable support body; and an image on the peelable support body, the image formed with the toner according to any one of claims 1 to 6.

9. A toner storage unit, storing the toner according to any one of claims 1 to 6.

10. An image forming apparatus, comprising: an electrostatic latent image bearer; an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image bearer; a developing unit that develops the electrostatic latent image with a developer including the toner according to any one of claims 1 to 6 to form a toner image; a transfer unit that transfers the toner image onto a peelable support body or onto a flexible recording medium having a surface roughness of 1 pm or more; and a fixing unit that fixes the toner image transferred onto the peelable support body or onto the flexible recording medium.

11. An image forming method, comprising: forming an electrostatic latent image on an electrostatic latent image bearer; developing the electrostatic latent image with a developer including the toner according to any one of claims 1 to 6 to form a toner image; transferring the toner image onto a peelable support body or onto a flexible recording medium having a surface roughness of 1 pm or more; and fixing the toner image transferred onto the peelable support body or onto the flexible recording medium.

12. The image forming method according to claim 11, wherein the toner image is formed as a layer contacting the peelable support body or the flexible recording medium.

13. The image forming method according to claim 11 or 12, wherein the flexible recording medium includes a fabric including fibers.

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