Photoresponsive Compounds

Abstract

To provide a compound which is fluidized and un-fluidized reversibly by light irradiation, has no significant coloration, improves fixability when used in a toner, and has excellent image stability and color reproducibility.SOLUTION: There is provided a compound represented by following general formula (1) which is fluidized and un-fluidized reversibly by light irradiation. Wherein, Z1 and Z2 are CH or N and Z1≠Z2, R1 is an aromatic hydrocarbon group having a substituent Ra selected from the group consisting of an alkyl group, an alkoxy group and a halogen atom, respectively, in two ortho-positions with respect to Z1, and R2 is a substituted or unsubstituted aromatic heterocyclic group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a photoresponsive compound that becomes fluid and reversibly non-fluid upon irradiation with light. [Background technology]

[0002] Photoresponsive materials are known as materials whose fluidity changes upon irradiation with light. For example, the azobenzene compounds (azobenzene derivatives) described in Patent Documents 1 and 2 undergo a phase change in association with an isomerization reaction upon irradiation with light.

[0003] This change in molecular structure is thought to induce a phase transition from a solid state to a fluid state. In addition, the film can be re-irradiated with light of a different wavelength, heated, or left in a dark place at room temperature. This causes a reverse reaction, causing the material to solidify again. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-256155 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-256291 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the azobenzene derivatives described in Patent Documents 1 and 2 are both It is available in yellow to orange coloring, and can reproduce the desired color when applied to industrial products such as toner and adhesives. Furthermore, according to the investigations of the present inventors, the azobenzene derivative By changing the substituents, the yellow to orange coloring can be adjusted somewhat. However, it was also found that it is impossible to make the material completely colorless or nearly colorless.

[0006] Therefore, an object of the present invention is to provide a compound that is fluidized by light irradiation, reversibly non-fluidized, and does not exhibit significant coloration, and that, when used in a toner, improves fixability and provides excellent image stability and color reproducibility. [Means for solving the problem]

[0007] The present inventors have conducted extensive research in view of the above-mentioned problems, and as a result have found that the above-mentioned problems can be solved by providing an azomethine compound having an aromatic hydrocarbon group and an aromatic heterocyclic group at both ends of a C=N bond, in which the aromatic hydrocarbon group has specific substituents at the two ortho positions relative to the C=N, thereby completing the present invention.

[0008] That is, the present invention provides a compound that becomes fluid and reversibly non-fluid upon irradiation with light, and is represented by the following general formula (1):

[0009] [ka]

[0010] During the ceremony, Z1 and Z2 are CH or N, and Z1≠Z2; R1 is a substituent R selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom at two ortho positions relative to Z1. a are aromatic hydrocarbon groups each having R2 is a substituted or unsubstituted aromatic heterocyclic group. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a compound that sufficiently ensures photoresponsiveness, that is, that it becomes fluid upon light irradiation and then reversibly becomes non-fluid, and that when used in a toner, improves fixing properties, has excellent image stability, and also has good color reproducibility. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic diagram showing the configuration of an image forming apparatus 100 used in an image forming method according to an embodiment of the present invention. [Figure 2] 2 is a schematic diagram of an irradiation unit 40 in the image forming apparatus 100. FIG. [Figure 3] FIG. 1 is a schematic diagram of an apparatus used in the photoresponsive adhesion test of the Examples to measure changes in adhesiveness of a compound upon irradiation with light. DETAILED DESCRIPTION OF THE INVENTION

[0013] Preferred embodiments of the present invention are described below. In this specification, the range "X to Y" means "X or more and Y or less." Unless otherwise specified, operations and measurements of physical properties are carried out under the conditions of room temperature (20 to 25°C) and a relative humidity of 40 to 50% RH.

[0014] <Photoresponsive compounds> One embodiment of the present invention is a compound that becomes fluid and reversibly non-fluid upon irradiation with light, and is represented by the following general formula (1):

[0015] [ka]

[0016] During the ceremony, Z1 and Z2 are CH or N, and Z1≠Z2; R1 is a substituent R selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom at two ortho positions relative to Z1. a are aromatic hydrocarbon groups each having R2 is a substituted or unsubstituted aromatic heterocyclic group.

[0017] Here, the above general formula (1) will be explained using one of the following specific examples. As shown in the following formula, an aromatic hydrocarbon group R1 such as a phenyl group is bonded to Z1 (CH in the following formula), and an aromatic heterocyclic group R2 which may be substituted is bonded to Z2 (N in the following formula). In this embodiment, the aromatic hydrocarbon group R1 has specific substituents R2 attached to both of the two carbon atoms at the ortho positions relative to Z1. a (CH3 group in the formula below).

[0018] [ka]

[0019] In this specification, the compound of the present invention is also referred to as a "photoresponsive compound." By having the above-mentioned specific structure, the compound can sufficiently ensure photoresponsiveness, in which the compound is fluidized by light irradiation and reversibly non-fluidized, and can provide a compound that, when used in a toner, improves fixability, has excellent image stability, and also has good color reproducibility.

[0020] As used herein, "fluidizing upon light irradiation and reversibly becoming non-fluid" refers to changing from a non-fluid state to a fluid state upon light irradiation and then returning to a non-fluid state. That is, the compound of the present invention is in a non-fluid solid state at room temperature and normal pressure when not irradiated with light, and softens and changes to a fluid state upon light irradiation. After cessation of light irradiation, the compound returns to a non-fluid solid state by leaving it in a dark place at room temperature or under visible light irradiation, or by heating. As used herein, "fluid state" refers to a state in which the compound is deformed by a small external force.

[0021] The mechanism by which such technical effects are achieved is presumed to be as follows. However, the technical scope of the present invention is not limited to such a mechanism. That is, azobenzene compounds are materials that absorb light and soften from a solid state (photo-induced phase transition), and this photo-induced phase transition is thought to occur when the crystal structure collapses due to cis-trans isomerization. The azobenzene compounds described in Patent Documents 1 and 2 undergo a phase change in association with an isomerization reaction due to light irradiation, but these compounds undergo n-π isomerization in the visible light region. *It has been found that this compound has a problem in that it is difficult to reproduce the desired color when applied to industrial products, since it exhibits strong absorption due to the transition and is colored orange.

[0022] In the present invention, by using a specific azomethine compound, it has been possible to provide a compound that becomes fluid upon light irradiation, becomes non-fluid reversibly, and does not have significant coloration. By introducing an azomethine moiety (C=N moiety) instead of an azobenzene moiety, the strong n-π * Absorption can be weakened, resulting in compounds that are not significantly colored.

[0023] Furthermore, when a non-fluidic trans isomer of a compound undergoes photoisomerization, it is thought that when the non-fluidic trans isomer is isomerized to the cis isomer upon photoirradiation, many of the trans isomers change to the cis isomer, destroying the ordered structure and inducing a phase transition, i.e., fluidization. Furthermore, when the cis isomers return to the trans isomer, the ordered structure is re-formed, inducing the non-fluidization. Therefore, in order to induce the fluidization phenomenon, many of the trans isomers must be isomerized to the cis isomer. However, azomethine compounds are generally known to undergo a faster isomerization from cis to trans than azobenzene compounds. Therefore, it was predicted that azomethine compounds with unsubstituted benzene rings at both ends of the C=N bond would be less favorable for inducing the reversible fluidization and non-fluidization phenomena.

[0024] Therefore, in the present invention, an azomethine compound has an aromatic hydrocarbon group and an aromatic heterocyclic group at both ends of a C=N bond, and has substituents R selected from the group consisting of alkyl groups, alkoxy groups, and halogen atoms at two ortho positions of the aromatic hydrocarbon group. a By introducing the above specific substituents R into the two ortho positions of the aromatic hydrocarbon group, we were able to efficiently induce the fluidization accompanying the photoisomerization reaction. aThis is thought to be because the presence of this substituent stabilizes the cis isomer and results in the production of a larger number of cis isomers than when the compound does not have this substituent or when it has this substituent at only one ortho position.

[0025] Furthermore, by incorporating the compound of the present invention into a toner, it is possible to obtain a toner that can be fixed by light irradiation, has excellent fixability, excellent image storability, and high color reproducibility. a By introducing the cis → trans reaction rate is reduced, and the cis isomer is further stabilized, allowing more cis isomers to be produced. This is thought to induce fluidization and promote melting, thereby improving fixability and image storage stability (image stability). Furthermore, the structure with specific substituents at the two ortho positions is thought to improve compatibility with the binder resin when used in toner, improving the toner's melting ability and ensuring image storage stability.

[0026] The compound represented by general formula (1) will be further explained below.

[0027] (Z1 and Z2) In one embodiment of the present invention, as described above, Z1 and Z2 are N or CH, provided that Z1≠Z2. When Z1 is CH and Z2 is N, the photo-melting property tends to be more excellent, which is more preferable.

[0028] (R1 and R2) In one embodiment of the present invention, R1 has, at the two ortho positions relative to Z1, a substituent R1 selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom. a and R2 is a substituted or unsubstituted aromatic heterocyclic group.

[0029] In one embodiment of the present invention, the aromatic hydrocarbon group has a predetermined substituent R aAlthough there are no particular limitations on the group, as long as it has each of the above, an aromatic hydrocarbon group having 6 to 30 carbon atoms is preferred, and examples thereof include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a biphenyl group. Such compounds can effectively cause fluidization and non-fluidization. Among them, a phenyl group, a naphthyl group, or a phenanthrenyl group is preferred, from the viewpoints that intermolecular packing is easily exhibited, and that they exhibit high thermal mobility upon trans-cis isomerization, making it easy to induce the fluidization phenomenon.

[0030] R a The number of carbon atoms in the alkyl group as R is not particularly limited, but it is, for example, an alkyl group having 1 to 10 carbon atoms, and preferably an alkyl group having 1 to 5 carbon atoms. a The number of carbon atoms in the alkoxy group as R is not particularly limited, but is, for example, an alkoxy group having 1 to 10 carbon atoms, preferably an alkoxy group having 1 to 5 carbon atoms. If the number is within the above range, the effects of the present invention can be more significantly obtained. In addition, it is preferable because synthesis is easy. Therefore, in a preferred embodiment of the present invention, a is an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogen atom. Among these, R a is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms.

[0031] In addition, the substituents R present at the two ortho positions relative to Z1 a are each independently selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom. a may be the same or different. a However, it is preferable that each of them is selected from the group consisting of an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a halogen atom.

[0032] Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, n-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, isopropyl, sec-butyl, and t-butyl groups. Examples of alkoxy groups having 1 to 10 carbon atoms include methoxy, ethoxy, n-propoxy, n-butoxy, n-pentyloxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, 1-methylpentyloxy, and 4-methyl-2-pentyloxy groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms.

[0033] In one embodiment of the present invention, the aromatic heterocyclic group is not particularly limited, but is preferably one having 2 to 30 carbon atoms. Furthermore, one having high electron donating properties is preferred. In a preferred embodiment of the present invention, R2 may be a substituted or unsubstituted thienyl group, furanyl group, pyrrolyl group, pyrazolyl group, imidazolyl group, pyridyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, benzothienyl group, benzimidazolyl group, indolyl group, isoindolyl group, quinolinyl group, isoquinolinyl group, quinazolinyl group, quinoxalinyl group, naphthyridinyl group, acridinyl group, carbazolyl group, or dibenzothienyl group. Such compounds can effectively induce fluidization and non-fluidization.

[0034] In one embodiment of the present invention, the aromatic hydrocarbon group is R aIn addition, the aromatic hydrocarbon group may have a substituent at a position other than the two ortho positions relative to Z1. The aromatic heterocyclic group may be unsubstituted or may have a substituent. These substituents are not particularly limited, but examples thereof include a halogen atom, a cyano group, a nitro group, an amino group, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 2 to 10 carbon atoms, an acyl group having 2 to 19 carbon atoms, and an alkoxycarbonyl group having 2 to 19 carbon atoms. Preferred are a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a dialkylamino group having 2 to 10 carbon atoms, an acyl group having 2 to 19 carbon atoms, and an alkoxycarbonyl group having 2 to 19 carbon atoms.

[0035] As described above, the photoinduced phase transition of azomethine compounds, like that of azobenzene compounds, is believed to occur due to the collapse of the crystal structure caused by cis-trans isomerization. Because azomethine compounds generally exhibit strong intermolecular π-π interactions, the photoinduced phase transition occurs only at the very outermost surface of the crystal structure. When the aromatic hydrocarbon group or aromatic heterocyclic group represented by R1 or R2 in the general formula (1) contains a substituent, the azomethine compound of the present invention forms a unique crystal structure in which an isotropically disordered structure due to the thermal motion of these substituents coexists within a periodic structure dominated by π-π interactions. Therefore, when the cis-trans isomerization reaction proceeds locally and the π-π interactions of the azomethine moiety are reduced, a chain reaction of isotropic melting occurs throughout the entire system. This is believed to facilitate the progression of cis-trans isomerization and facilitate fluidization.

[0036] In particular, in general formula (1), R1 is preferably a phenyl group further having a substituent at the para position relative to Z1 selected from the group consisting of an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a dialkylamino group having 2 to 10 carbon atoms, an acyl group having 2 to 19 carbon atoms, and an alkoxycarbonyl group having 2 to 19 carbon atoms. This structure results in the generation of lattice defects that favor cis-trans isomerization, the development of free volume, and the reduction of π-π interactions. This is thought to facilitate the progression of cis-trans isomerization and facilitate the development of fluidization. In particular, introducing these substituents at the para position of the benzene ring facilitates crystal collapse, improves photomeltability, and, when used in a toner, enhances fixability and image stability. Among these, alkyl groups having 1 to 18 carbon atoms, alkoxy groups having 1 to 18 carbon atoms, and dialkylamino groups having 2 to 10 carbon atoms are even more preferred due to their higher thermal mobility.

[0037] With regard to the number of carbon atoms in the substituents, the alkyl group is more preferably an alkyl group having 1 to 12 carbon atoms, and even more preferably an alkyl group having 4 to 12 carbon atoms. The alkoxy group is more preferably an alkoxy group having 1 to 12 carbon atoms, and even more preferably an alkoxy group having 4 to 12 carbon atoms. The dialkylamino group is more preferably a dialkylamino group having 2 to 8 carbon atoms, and even more preferably a dialkylamino group having 4 to 6 carbon atoms. The acyl group is more preferably an acyl group having 2 to 13 carbon atoms, and even more preferably an acyl group having 5 to 13 carbon atoms. The alkoxycarbonyl group is more preferably an alkoxycarbonyl group having 2 to 13 carbon atoms, and even more preferably an alkoxycarbonyl group having 5 to 13 carbon atoms. The introduction of a long-chain substituent makes the crystal more easily collapsed, improving photo-meltability, and when used in a toner, the fixability and image stability can be further improved.

[0038] Examples of the alkyl group having 1 to 18 carbon atoms are not particularly limited, and include, for example, straight-chain alkyl groups such as methyl group, ethyl group, n-propyl group, n-butyl group, isobutyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, and n-hexadecyl group; isopropyl group, sec-butyl group, t Examples of branched alkyl groups include 1-butyl group, 1-methylpentyl group, 4-methyl-2-pentyl group, 3,3-dimethylbutyl group, 2-ethylbutyl group, 1-methylhexyl group, t-octyl group, 1-methylheptyl group, 2-ethylhexyl group, 2-propylpentyl group, 2,2-dimethylheptyl group, 2,6-dimethyl-4-heptyl group, 3,5,5-trimethylhexyl group, 1-methyldecyl group, and 1-hexylheptyl group.

[0039] Examples of alkoxy groups having 1 to 18 carbon atoms include linear alkoxy groups such as methoxy, ethoxy, n-propoxy, n-butoxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, n-tridecyloxy, n-tetradecyloxy, n-pentadecyloxy, and n-hexadecyloxy; 1-methylpentyloxy, 4-methyl-2-methylpentyloxy; Examples of branched alkoxy groups include t-pentyloxy group, 3,3-dimethylbutyloxy group, 2-ethylbutyloxy group, 1-methylhexyloxy group, t-octyloxy group, 1-methylheptyloxy group, 2-ethylhexyloxy group, 2-propylpentyloxy group, 2,2-dimethylheptyloxy group, 2,6-dimethyl-4-heptyloxy group, 3,5,5-trimethylhexyloxy group, 1-methyldecyloxy group, and 1-hexylheptyloxy group.

[0040] Examples of alkylamino groups having 1 to 10 carbon atoms include methylamino, ethylamino, n-propylamino, n-butylamino, isobutylamino, n-hexylamino, n-heptylamino, n-octylamino, n-nonylamino, and n-decylamino groups.

[0041] Examples of the dialkylamino group having 2 to 10 carbon atoms include a dimethylamino group, a diethylamino group, a di-n-propylamino group, a di-n-butylamino group, a di-isobutylamino group, and a methylethylamino group.

[0042] Examples of the acyl group having 2 to 19 carbon atoms include saturated or unsaturated, straight-chain or branched-chain acyl groups, such as an acetyl group, a propanoyl group (propionyl group), a butanoyl group (butyryl group), an isobutanoyl group (isobutyryl group), a pentanoyl group (valeryl group), an isopentanoyl group (isovaleryl group), a sec-pentanoyl group (2-methylbutyryl group), a t-pentanoyl group (pivalyl group), and the like. Examples of hydroxyl groups include hexanoyl, hexanoyl, heptanoyl, octanoyl, t-octanoyl (2,2-dimethylhexanoyl), 2-ethylhexanoyl, nonanoyl, isononanoyl, decanoyl, isodecanoyl, undecanoyl, lauroyl, myristoyl, palmitoyl, stearoyl, behenoyl, undecylenoyl, and oleoyl groups.

[0043] Examples of the alkoxycarbonyl group having 2 to 19 carbon atoms include linear or branched alkoxycarbonyl groups such as a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group, an n-hexyloxycarbonyl group, an n-heptyloxycarbonyl group, an n-octyloxycarbonyl group, an n-nonyloxycarbonyl group, an n-decyloxycarbonyl group, an n-undecyloxycarbonyl group, an n-dodecyloxycarbonyl group, an n-tridecyloxycarbonyl group, an n-tetradecyloxycarbonyl group, an n-pentadecyloxycarbonyl group, and an n-hexadecyloxycarbonyl group; branched alkoxycarbonyl groups such as a butyl group, a 4-methyl-2-pentyloxycarbonyl group, a 3,3-dimethylbutyloxycarbonyl group, a 2-ethylbutyloxycarbonyl group, a 1-methylhexyloxycarbonyl group, a t-octyloxycarbonyl group, a 1-methylheptyloxycarbonyl group, a 2-ethylhexyloxycarbonyl group, a 2-propylpentyloxycarbonyl group, a 2,2-dimethylheptyloxycarbonyl group, a 2,6-dimethyl-4-heptyloxycarbonyl group, a 3,5,5-trimethylhexyloxycarbonyl group, a 1-methyldecyloxycarbonyl group, and a 1-hexylheptyloxycarbonyl group.

[0044] In one embodiment of the present invention, in the compound represented by the general formula (1), in the aromatic heterocyclic group of R2, a hydrogen atom is preferably bonded to at least one carbon atom bonded adjacent to the carbon atom directly bonded to Z2. This further stabilizes the cis isomer, thereby more effectively inducing fluidization due to photoisomerization, and the effects of the present invention can be more significantly achieved. More preferably, in the aromatic heterocyclic group of R2, both of the two carbon atoms bonded adjacent to the carbon atom directly bonded to Z2 are bonded to hydrogen atoms. This increases the probability of intramolecular CH-π interactions occurring with the aromatic hydrocarbon ring in the cis isomer. Therefore, by further stabilizing the cis isomer, fluidization due to photoisomerization is more effectively manifested, and the effects of the present invention can be more significantly achieved.

[0045] According to one embodiment of the present invention, in the general formula (1), R2 is a compound represented by the following formula:

[0046] [ka]

[0047] In the formula, R c is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms. This allows the desired effects of the present invention (particularly the effects of improving fixability and image stability when used in a toner) to be efficiently achieved. Preferably, R c is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.

[0048] <Method for producing photoresponsive compound> The method for synthesizing the azomethine compound of the present invention is not particularly limited. For example, when R1 is a predetermined substituent R a In the case of preparing an azomethine derivative containing a benzene ring having the formula a The compound can be synthesized by reacting an aniline derivative having the formula: with a pyrazole carbaldehyde derivative.

[0049] For example, R1 may be a predetermined substituent R a In the case of preparing an azomethine derivative containing a benzene ring having the formula a A benzaldehyde derivative having the formula: is reacted with an aminopyrazole derivative.

[0050] Specifically, for example, a compound of general formula (1) in which Z1 is CH, Z2 is N, R1 is a 2,6-dimethyl-4-hexyloxyphenyl group, and R2 is a 1-methyl-4-pyrazolyl group can be synthesized by the following scheme.

[0051] The target azomethine compound can be obtained by reacting 4-hexyloxy-2,6-dimethylbenzaldehyde and 1-methyl-1H-pyrazol-4-amine in ethanol (EtOH) with heating and stirring, filtering the reaction solution, washing the resulting powder with cooled ethanol, and recrystallizing it with methanol / ethanol. The temperature during heating and stirring is preferably in the range of 0°C to 100°C, more preferably in the range of 30°C to 70°C, and even more preferably in the range of 40°C to 60°C.

[0052] [ka]

[0053] Azomethine compounds other than those mentioned above can also be synthesized in a similar manner by referring to the above scheme and changing the raw materials as appropriate.

[0054] The azomethine compounds of the present invention can be used singly or in combination of two or more kinds.

[0055] The molecular weight of the compound represented by the general formula (1) of the present invention is not particularly limited, but is preferably 100 or more and less than 1,000, and more preferably 100 or more and 800 or less. The compound represented by the general formula (1) of the present invention does not include a polymer. In a preferred embodiment, the compound represented by the general formula (1) is configured without including a repeating unit. In a preferred embodiment, the compound represented by the general formula (1) is not obtained by polymerizing a monomer containing a polymerizable group.

[0056] One embodiment of the present invention relates to a compound that becomes fluid and reversibly becomes non-fluid upon irradiation with light, and is represented by the following general formula (1):

[0057] [ka]

[0058] (In the general formula (1), Z1 and Z2 are CH or N, Z1≠Z2, and R1 has a substituent R selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom at two ortho positions relative to Z1.) a and R2 is a substituted or unsubstituted aromatic heterocyclic group.); However, compounds other than those in (1) and (2) below: (1) A compound represented by the following chemical formula 1 that can be reversibly fluidized and non-fluidized upon irradiation with light:

[0059] [ka]

[0060] In the above Chemical Formula 1, X is NR 10 , O or S; Z1 and Z2 are each independently N or CH, and Z1≠Z2; R1 and R2 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an alkoxycarbonyl group, a cyano group, a nitro group, or a hydroxy group; R3 and R4 each independently represent a group represented by Chemical Formula 2, a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an alkoxycarbonyl group, a cyano group, a nitro group, or a hydroxy group; In this case, either R3 or R4 is a group represented by the above-mentioned Chemical Formula 2, R 10 is a hydrogen atom, a halogen atom, an alkyl group, an alkoxycarbonyl group, or a hydroxy group, In the above Chemical Formula 2, R5 to R9 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an alkoxycarbonyl group, a cyano group, a nitro group, or a hydroxy group; In this case, at least one of R5 to R9 is an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, an acyl group having 2 to 19 carbon atoms, or an alkoxycarbonyl group having 2 to 19 carbon atoms, R5 and R9 are each independently selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom.

[0061] (2) A compound represented by the following formula:

[0062] [ka]

[0063] <Fluidization and reversible non-fluidization by light irradiation> The wavelength of the irradiated light when the compound of the present invention is fluidized by light irradiation is preferably in the range of 280 nm to 480 nm, more preferably in the range of 300 nm to 420 nm, and even more preferably in the range of 330 nm to 420 nm. Within this range, the crystals are more easily broken down (improved light melting properties), resulting in improved fixability. Furthermore, when fluidizing, heat or pressure may be applied in addition to light irradiation to promote fluidization. By irradiating with light of the above wavelength, fluidization can be achieved with less heat or pressure, even when heat or pressure is applied. Therefore, by incorporating the compound of the present invention into a toner, fixation at the above wavelength becomes possible, and a toner with excellent fixability and high color reproducibility can be obtained.

[0064] The wavelength range includes a portion of visible light. Therefore, it is desirable that the compound of the present invention does not become fluid simply by being exposed to sunlight (natural light) or light from a fluorescent lamp, and that the compound be more fluidized under low-cost conditions with as low an irradiation dose and irradiation time as possible. From this perspective, the irradiation conditions for the light to be applied when the compound is fluidized are preferably an irradiation dose of 0.1 J / cm. 2 More than 200J / cm 2 Within the range of 0.1 J / cm 2 More than 100J / cm 2Within the range of 0.1 J / cm 2 More than 50J / cm 2 It is within the following range:

[0065] When fluidizing the compound, the compound may be heated in addition to the light irradiation. This allows the compound to be fluidized with a lower irradiation dose. The heating temperature in this case is, for example, in the range of 20°C to 200°C, preferably in the range of 20°C to 150°C.

[0066] On the other hand, the conditions for immobilizing (resolidifying) the compound of the present invention are preferably room temperature (within the range of 25±15°C) and left to stand (in a natural environment). In this case, it is best to store it in a dark place, but it may also be exposed to visible light such as natural light or fluorescent light. It is more preferable to apply heat during the immobilization process. Light may also be applied.

[0067] When the compound is heated to make it non-fluid, the heating temperature is preferably in the range of 0°C or higher and 200°C or lower, more preferably in the range of 20°C or higher and 150°C or lower.

[0068] [Toner composition] One embodiment of the present invention is a toner containing the compound of the present invention. By incorporating the compound of the present invention into a toner, it is possible to obtain a toner that can be fixed by light irradiation, has excellent fixability, and exhibits high color reproducibility. The term "toner" refers to toner base particles or an aggregate of toner particles. The toner particles are preferably toner base particles to which an external additive has been added, but the toner base particles can also be used as they are. In the present invention, when there is no particular need to distinguish between toner base particles, toner particles, and toner, they are also simply referred to as "toner."

[0069] (binder resin) The toner of the present invention preferably further contains a binder resin in addition to the specified azomethine compound of the present invention. It is generally known that toner particles having a substantially uniform particle size and shape can be produced by utilizing the emulsion aggregation method described below as a toner production method. Toner can also be produced by using the azomethine compound alone or by simply adding other additives such as a colorant or a release agent without using a binder resin. By using the azomethine compound in combination with a binder resin, toner particles having a substantially uniform particle size and shape can be produced by salting out in the emulsion aggregation method. Therefore, a toner containing the azomethine compound and a binder resin can be more easily applied to electrophotographic toners.

[0070] The binder resin can be any resin generally used as a binder resin for toner, without any restrictions. Examples of binder resins that can be used include styrene resins, acrylic resins, styrene-acrylic resins, polyester resins, silicone resins, olefin resins, amide resins, and epoxy resins. These binder resins can be used alone or in combination of two or more.

[0071] Among these, from the viewpoint of achieving low viscosity when melted and having high sharp melting properties, the binder resin preferably contains at least one selected from the group consisting of styrene resin, acrylic resin, styrene-acrylic resin, and polyester resin, and more preferably contains at least one selected from the group consisting of styrene-acrylic resin and polyester resin. By adopting such an embodiment, image strength can be increased.

[0072] (styrene acrylic resin) The styrene-acrylic resin referred to in the present invention is a polymer containing at least a structural unit derived from a styrene monomer and a structural unit derived from a (meth)acrylic acid ester monomer. Here, the styrene monomer includes not only styrene represented by the structural formula CH2=CH-C6H5, but also structures having known side chains or functional groups in the styrene structure.

[0073] Examples of styrene monomers include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pt-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, and pn-dodecylstyrene.

[0074] Furthermore, a (meth)acrylic acid ester monomer is one having a functional group with an ester bond in the side chain. Specifically, it includes vinyl ester compounds such as an acrylic acid ester monomer represented by CH2=CHCOOR (R is an alkyl group) and a methacrylic acid ester monomer represented by CH2=C(CH3)COOR (R is an alkyl group). Note that the (meth)acrylic acid in a (meth)acrylic acid ester monomer refers to acrylic acid and methacrylic acid.

[0075] Examples of (meth)acrylic acid ester monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl (meth)acrylate, dodecyl (meth)acrylate, phenyl (meth)acrylate, diethylaminoethyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate.

[0076] The styrene monomer and the (meth)acrylic acid ester monomer can be used either alone or in combination of two or more kinds.

[0077] The contents of the structural units derived from styrene monomers and the structural units derived from (meth)acrylic acid ester monomers in the styrene-acrylic resin are not particularly limited and can be appropriately adjusted from the viewpoint of controlling the softening point and glass transition temperature of the binder resin. Specifically, the content of the structural units derived from styrene monomers is preferably 40 to 95% by mass, and more preferably 50 to 90% by mass, of all structural units constituting the styrene-acrylic resin. Furthermore, the content of the structural units derived from (meth)acrylic acid ester monomers is preferably 5 to 60% by mass, and more preferably 10 to 50% by mass, of all structural units.

[0078] The styrene-acrylic resin may further contain structural units derived from other monomers besides the styrene monomer and the (meth)acrylic acid ester monomer, as necessary. Examples of such other monomers include vinyl monomers. Examples of vinyl monomers that can be used in combination to form the styrene-acrylic copolymer of the present invention are listed below, but the vinyl monomers that can be used in combination are not limited to those listed below.

[0079] (1) Olefins Ethylene, propylene, isobutylene, etc. (2) Vinyl esters Vinyl propionate, vinyl acetate, vinyl benzoate, etc. (3) Vinyl ethers Vinyl methyl ether, vinyl ethyl ether, etc. (4) Vinyl ketones Vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone, etc. (5) N-vinyl compounds N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone, etc. (6) Other Vinyl compounds such as vinylnaphthalene and vinylpyridine, acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide, and the like.

[0080] It is also possible to prepare a resin with a crosslinked structure using a polyfunctional vinyl monomer. Furthermore, it is also possible to use a vinyl monomer having an ionic dissociative group on the side chain. Specific examples of the ionic dissociative group include a carboxyl group, a sulfonic acid group, and a phosphate group. Specific examples of vinyl monomers having these ionic dissociative groups are shown below.

[0081] Specific examples of vinyl monomers having a carboxyl group include acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, maleic acid monoalkyl esters, and itaconic acid monoalkyl esters.

[0082] When forming the styrene-acrylic resin used in the present invention, the contents of the styrene monomer and (meth)acrylic ester monomer are not particularly limited and can be appropriately adjusted from the viewpoint of controlling the softening point temperature and glass transition temperature of the binder resin. Specifically, the content of the styrene monomer is preferably 40 to 95 mass% and more preferably 50 to 90 mass% of the total monomers constituting the styrene-acrylic resin. Furthermore, the content of the (meth)acrylic ester monomer is preferably 5 to 60 mass% and more preferably 10 to 50 mass% of the total monomers constituting the styrene-acrylic resin.

[0083] The method for forming the styrene-acrylic resin is not particularly limited, and examples thereof include a method of polymerizing a monomer using a known oil-soluble or water-soluble polymerization initiator. If necessary, a known chain transfer agent such as n-octyl mercaptan may be used. Examples of oil-soluble polymerization initiators that can be used include the azo- or diazo-based polymerization initiators and peroxide-based polymerization initiators shown below.

[0084] Examples of the azo or diazo polymerization initiator include 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), and 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile.

[0085] Examples of the peroxide polymerization initiator include benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis-(4,4-t-butylperoxycyclohexyl)propane, and tris-(t-butylperoxy)triazine.

[0086] When styrene-acrylic resin particles are formed by emulsion polymerization, a water-soluble radical polymerization initiator can be used, such as persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, and hydrogen peroxide.

[0087] The polymerization temperature varies depending on the types of monomers and polymerization initiators used, but is preferably 50 to 100° C., and more preferably 55 to 90° C. The polymerization time also varies depending on the types of monomers and polymerization initiators used, but is preferably, for example, 2 to 12 hours.

[0088] The styrene-acrylic resin particles formed by emulsion polymerization can be configured to have two or more layers made of resins with different compositions. In this case, a multi-stage polymerization method can be used, in which a polymerization initiator and a polymerizable monomer are added to a dispersion of resin particles prepared by a conventional emulsion polymerization treatment (first-stage polymerization), and the system is polymerized (second-stage and third-stage polymerization).

[0089] (polyester resin) The polyester resin is obtained by a polycondensation reaction between a divalent or higher carboxylic acid (a polycarboxylic acid component) and a divalent or higher alcohol (a polyhydric alcohol component). The polyester resin may be amorphous or crystalline.

[0090] The valence of each of the polycarboxylic acid component and the polyhydric alcohol component is preferably 2 to 3, and more preferably 2. That is, the polycarboxylic acid component preferably contains a dicarboxylic acid component, and the polyhydric alcohol component preferably contains a diol component.

[0091] Examples of the dicarboxylic acid component include saturated aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid (dodecanedioic acid), 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, and 1,18-octadecanedicarboxylic acid; and methylenesuccinic acid. unsaturated aliphatic dicarboxylic acids such as fumaric acid, maleic acid, 3-hexenedioic acid, 3-octenedioic acid, and dodecenylsuccinic acid; unsaturated aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, t-butylisophthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-phenylenediacetic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, and anthracenedicarboxylic acid; and lower alkyl esters and acid anhydrides of these dicarboxylic acids can also be used. The dicarboxylic acid component can be used alone or in combination of two or more.

[0092] In addition, trivalent or higher polyvalent carboxylic acids such as trimellitic acid and pyromellitic acid, anhydrides thereof, or alkyl esters having 1 to 3 carbon atoms can also be used.

[0093] Examples of the diol component include ethylene glycol, 1,2-propanediol, 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, 1,20-eicosanediol, and neopentane. Examples of the diol component include saturated aliphatic diols such as ethylene glycol; unsaturated aliphatic diols such as 2-butene-1,4-diol, 3-butene-1,4-diol, 2-butyne-1,4-diol, 3-butyne-1,4-diol, and 9-octadecene-7,12-diol; and aromatic diols such as bisphenols such as bisphenol A and bisphenol F, and alkylene oxide adducts of bisphenols such as ethylene oxide adducts and propylene oxide adducts of these bisphenols. Derivatives of these diols can also be used. The diol component may be used alone or in combination of two or more.

[0094] The method for producing the polyester resin is not particularly limited, and the polyester resin can be produced by polycondensing (esterifying) the polycarboxylic acid component and the polyhydric alcohol component using a known esterification catalyst.

[0095] Catalysts that can be used in the production of polyester resins include alkali metal compounds such as sodium and lithium; compounds containing Group 2 elements such as magnesium and calcium; compounds of metals such as aluminum, zinc, manganese, antimony, titanium, tin, zirconium, and germanium; phosphorous compounds; phosphate compounds; and amine compounds. Specific examples of tin compounds include dibutyltin oxide (dibutyltin oxide), tin octoate, tin dioctoate, and salts thereof. Titanium compounds include titanium alkoxides such as tetra-n-butyl titanate (Ti(On-Bu)4), tetraisopropyl titanate, tetramethyl titanate, and tetrastearyl titanate; titanium acylates such as polyhydroxytitanium stearate; and titanium chelates such as titanium tetraacetylacetonate, titanium lactate, and titanium triethanolamine. Germanium compounds include germanium dioxide. Aluminum compounds include polyaluminum hydroxide, aluminum alkoxides, and tributylaluminate. These may be used alone or in combination of two or more.

[0096] The polymerization temperature is not particularly limited, but is preferably 70 to 250° C. The polymerization time is also not particularly limited, but is preferably 0.5 to 10 hours. During the polymerization, the reaction system may be reduced in pressure, if necessary.

[0097] When the toner of the present invention contains a binder resin, the content of the azomethine compound varies depending on the type of compound and resin. From the viewpoint of fixability and color reproducibility, the azomethine compound:binder resin ratio is preferably in the range of 5:95 to 95:5 (mass ratio), more preferably 10:90 to 90:10 (mass ratio), more preferably 10:90 to 80:20 (mass ratio), and even more preferably 10:90 to 70:30 (mass ratio). Within this range, the photo-induced phase transition of the compound having the azomethine moiety is easily caused, and the toner softens at a sufficient rate upon light irradiation. When two or more azomethine compounds are used, the total amount thereof is preferably in the above range. When two or more binder resins are used, the total amount thereof is preferably in the above range.

[0098] From the viewpoints of fixability, heat-resistant storage stability, etc., the glass transition temperature (Tg) of the toner is preferably 25 to 100° C., and more preferably 30 to 80° C. When the toner contains a binder resin, the glass transition temperature (Tg) of the toner can be adjusted by the content of the binder resin, the type of the binder resin, the molecular weight, etc.

[0099] The toner of the present invention may be particles having a single layer structure or particles having a core-shell structure. The types of binder resins used for the core particles and shell portion of the core-shell structure are not particularly limited.

[0100] <Coloring agent> The toner of the present invention may further contain a colorant. Since the compound of the present invention does not cause significant coloring, a toner with high color reproducibility of the colorant can be obtained. As the colorant, generally known dyes and pigments can be used.

[0101] Examples of colorants for obtaining black toner include carbon black, magnetic materials, iron-titanium composite oxide black, etc. Carbon black includes channel black, furnace black, acetylene black, thermal black, and lamp black, while magnetic materials include ferrite and magnetite.

[0102] Examples of colorants for obtaining yellow toner include dyes such as CI Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, and 162; and pigments such as CI Pigment Yellow 14, 17, 74, 93, 94, 138, 155, 180, and 185.

[0103] Colorants for obtaining magenta toner include dyes such as CI Solvent Red 1, 49, 52, 58, 63, 111, and 122; and pigments such as CI Pigment Red 5, 48:1, 53:1, 57:1, 122, 139, 144, 149, 166, 177, 178, and 222.

[0104] Examples of colorants for obtaining cyan toner include dyes such as CI Solvent Blue 25, 36, 60, 70, 93, and 95; and pigments such as CI Pigment Blue 1, 7, 15, 15:3, 60, 62, 66, and 76.

[0105] The colorants for obtaining the toner of each color may be used alone or in combination of two or more.

[0106] The content of the colorant in the toner particles (toner base particles) before the addition of external additives is preferably 0.5 to 20% by mass, and more preferably 2 to 10% by mass.

[0107] <Release agent> The toner according to the present invention may further contain a release agent. By incorporating a release agent into the toner, a toner having excellent fixability and color reproducibility can be obtained when thermal fixing is performed together with light irradiation.

[0108] The release agent used is not particularly limited, and various known waxes can be used. Examples of waxes include polyolefins such as low-molecular-weight polypropylene, polyethylene, or oxidized low-molecular-weight polypropylene or polyethylene, paraffin wax, and synthetic ester wax. Among them, paraffin wax is preferably used from the viewpoint of improving the storage stability of the toner.

[0109] The content of the release agent in the toner base particles is preferably 1 to 30% by mass, and more preferably 3 to 15% by mass.

[0110] <Charge control agent> The toner according to the present invention may contain a charge control agent. The charge control agent to be used is not particularly limited as long as it is a substance that can impart positive or negative charge by frictional charging and is colorless, and various known positively and negatively chargeable charge control agents can be used.

[0111] The content of the charge control agent in the toner base particles is preferably 0.01 to 30% by mass, and more preferably 0.1 to 10% by mass.

[0112] The amount of the compound of the present invention in the toner is not particularly limited, but from the viewpoint of efficient fluidization and image strength, it is, for example, in the range of 5 to 95% by mass with respect to the total amount of the binder resin, colorant, release agent, and compound of the present invention that constitute the toner.

[0113] <External additives> In order to improve the fluidity, chargeability, cleaning properties, etc. of the toner, the toner according to the present invention may be constructed by adding external additives such as a fluidizing agent, a cleaning aid, etc., which are so-called post-treatment agents, to the toner base particles.

[0114] Examples of external additives include inorganic oxide particles such as silica particles, alumina particles, and titanium oxide particles; inorganic stearic acid compound particles such as aluminum stearate particles and zinc stearate particles; and inorganic titanic acid compound particles such as strontium titanate particles and zinc titanate particles. These inorganic particles may be hydrophobized as necessary. These may be used alone or in combination of two or more.

[0115] Among these, preferred external additives are, for example, sol-gel silica particles, silica particles whose surfaces have been hydrophobized (hydrophobic silica particles), or titanium oxide particles (hydrophobic titanium oxide particles), and it is more preferred to use at least two or more types of external additives among these.

[0116] The number average primary particle size of the external additive is preferably within a range of 1 to 200 nm, more preferably 10 to 180 nm.

[0117] The amount of these external additives added is preferably 0.05 to 5% by mass, and more preferably 0.1 to 3% by mass, in the toner.

[0118] In one embodiment of the present invention, the amount of these external additives added is preferably 0.5 to 5% by mass, and more preferably 0.1 to 3% by mass, based on the toner base particles.

[0119] <Average particle size of toner> The average particle size of the toner (and the average particle size of the toner base particles) is preferably 4 to 20 μm, more preferably 5 to 15 μm, in terms of volume-based median diameter (D50). When the volume-based median diameter (D50) is within the above range, transfer efficiency is increased, and image quality of halftones, fine lines, dots, etc. is improved.

[0120] The volume-based median diameter (D50) can be measured and calculated using a measuring device consisting of a "Coulter Counter 3" (manufactured by Beckman Coulter, Inc.) connected to a computer system (manufactured by Beckman Coulter, Inc.) equipped with data processing software "Software V3.51."

[0121] Specifically, 0.02 g of the measurement sample (toner or toner base particles) is added to 20 mL of surfactant solution (a surfactant solution prepared by diluting, for example, a neutral detergent containing surfactant components 10 times with pure water in order to disperse the toner particles), and after mixing, ultrasonic dispersion is performed for 1 minute to prepare a dispersion. This dispersion is then pipetted into a beaker containing an "ISOTON II" (manufactured by Beckman Coulter, Inc.) in the sample stand until the concentration indicated on the measuring device reaches 8%.

[0122] Here, by setting the display density within the above range, reproducible measurement values can be obtained. Then, in the measurement device, the number of particles to be measured is set to 25,000, the aperture diameter is set to 50 μm, the measurement range of 1 to 30 μm is divided into 256 parts to calculate the frequency value, and the particle size of the largest 50% of the volume cumulative fraction is taken as the volume-based median diameter (D50).

[0123] [Toner manufacturing method] The method for producing the toner of the present invention is not particularly limited. For example, when the toner is made from only the compound of the present invention, a production method can be used that includes pulverizing the compound using an apparatus such as a hammer mill, feather mill, or counter jet mill, and then classifying the resulting particles to a desired particle size using a dry classifier such as a spin air sieve, a crusher, or a micron classifier. When producing a toner that further contains a colorant, the compound and the colorant can be dissolved in a solvent that dissolves both the compound of the present invention and the colorant to form a solution, followed by removing the solvent and then pulverizing and classifying the resultant in the same manner as above.

[0124] In particular, a toner containing the compound of the present invention, a binder resin, and, if necessary, additives such as a colorant, is preferably produced by a production method utilizing an emulsion aggregation method, which allows easy control of particle size and shape.

[0125] Such a manufacturing method is (1A) Binder resin particle dispersion liquid preparation step of preparing a binder resin particle dispersion liquid (1B) Compound particle dispersion preparation step for preparing a dispersion of particles of the compound of the present invention (1C) A colorant particle dispersion preparation step for preparing a colorant particle dispersion as needed. (2) An association step in which a flocculant is added to an aqueous medium containing compound particles, binder resin particles, and, if necessary, colorant particles, to promote salting out and simultaneously cause aggregation and fusion to form associated particles. (3) A ripening process in which toner base particles are formed by controlling the shape of the aggregated particles (4) A filtering and washing process in which the toner base particles are separated from the aqueous medium and surfactants and the like are removed from the toner base particles. (5) A drying process for drying the washed toner base particles. (6) Adding external additives to the dried toner base particles It is preferable that the method includes the steps of:

[0126] The steps (1A) to (1C) will be explained below.

[0127] (1A) Binder resin particle dispersion preparation step In this step, resin particles are formed by a conventionally known emulsion polymerization or the like, and the resin particles are aggregated and fused to form binder resin particles. As an example, polymerizable monomers constituting the binder resin are introduced into an aqueous medium and dispersed therein, and these polymerizable monomers are polymerized using a polymerization initiator to prepare a dispersion of binder resin particles.

[0128] Further, as a method for obtaining a binder resin particle dispersion, in addition to the above-mentioned method of polymerizing a polymerizable monomer in an aqueous medium using a polymerization initiator, for example, a method of performing a dispersion treatment in an aqueous medium without using a solvent, or a method of dissolving a crystalline resin in a solvent such as ethyl acetate to prepare a solution, emulsifying and dispersing the solution in an aqueous medium using a disperser, and then performing a solvent removal treatment, etc. may be mentioned.

[0129] In this case, if necessary, a release agent may be added to the binder resin in advance. For dispersion, it is also preferable to carry out the polymerization in the presence of a known surfactant (for example, an anionic surfactant such as polyoxyethylene (2) dodecyl ether sodium sulfate, sodium dodecyl sulfate, or dodecylbenzenesulfonic acid).

[0130] The volume-based median diameter of the binder resin particles in the dispersion is preferably 50 to 300 nm. The volume-based median diameter of the binder resin particles in the dispersion can be measured by dynamic light scattering using a "Microtrac UPA-150" (manufactured by Nikkiso Co., Ltd.).

[0131] (1B) Compound particle dispersion preparation process This compound particle dispersion preparation step is a step of dispersing the compound of the present invention in the form of fine particles in an aqueous medium to prepare a dispersion of particles of the compound.

[0132] In preparing a dispersion of particles of the compound, an emulsion of the compound is first prepared, for example, by dissolving the compound in an organic solvent and then emulsifying the resulting solution in an aqueous medium.

[0133] The method for dissolving the compound in the organic solvent is not particularly limited, and examples thereof include a method in which the compound is added to the organic solvent and stirred and mixed to dissolve the compound. The amount of the compound added is preferably 5 parts by mass or more and 100 parts by mass or less, more preferably 10 parts by mass or more and 50 parts by mass or less, relative to 100 parts by mass of the organic solvent.

[0134] Next, the obtained solution of the compound is mixed with an aqueous medium and stirred using a known dispersing machine such as a homogenizer, whereby the compound is turned into droplets and emulsified in the aqueous medium, thereby preparing an emulsion of the compound.

[0135] The amount of the solution of the compound added is preferably 10 parts by mass or more and 110 parts by mass or less relative to 100 parts by mass of the aqueous medium.

[0136] When the compound solution and the aqueous medium are mixed, the temperatures of the compound solution and the aqueous medium are each in a temperature range below the boiling point of the organic solvent, and are preferably from 20° C. to 80° C., more preferably from 30° C. to 75° C. When the compound solution and the aqueous medium are mixed, the temperatures of the compound solution and the aqueous medium may be the same or different, and are preferably the same.

[0137] The stirring conditions for the disperser are, for example, when the capacity of the stirring vessel is 1 to 3 L, preferably a rotation speed of 7000 rpm to 20000 rpm, and a stirring time of 10 minutes to 30 minutes.

[0138] The dispersion of the compound particles is prepared by removing the organic solvent from the emulsion of the compound. Examples of the method for removing the organic solvent from the emulsion of the compound include known methods such as blowing air, heating, reducing pressure, or a combination of these.

[0139] For example, the emulsion of the compound is heated, for example, in an inert gas atmosphere such as nitrogen, preferably at 25°C to 90°C, more preferably at 30°C to 80°C, until, for example, about 80% by mass to 95% by mass of the initial amount of organic solvent is removed (for example, 20 to 150 minutes), thereby removing the organic solvent from the aqueous medium and preparing a dispersion of the compound particles in which the particles of the compound are dispersed in the aqueous medium.

[0140] The mass average particle diameter of the compound particles in the dispersion of the compound particles is preferably 90 nm or more and 1200 nm or less. The mass average particle diameter can be set within the above range by appropriately adjusting the viscosity when the compound is mixed with an organic solvent, the mixing ratio of the compound solution to the aqueous medium, the stirring speed of the disperser when preparing the emulsion of the compound, etc. The mass average particle diameter of the compound particles in the dispersion of the compound particles can be measured using a Microtrac UPA-150 (manufactured by Nikkiso Co., Ltd.) or an electrophoretic light scattering photometer "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.).

[0141] <Organic solvents> The organic solvent used in this step is not particularly limited as long as it can dissolve the compound. Specific examples include esters such as ethyl acetate and butyl acetate, ethers such as diethyl ether, diisopropyl ether and tetrahydrofuran, ketones such as acetone and methyl ethyl ketone, saturated hydrocarbons such as hexane and heptane, and halogenated hydrocarbons such as dichloromethane, dichloroethane and carbon tetrachloride.

[0142] These organic solvents can be used alone or in combination. Among these organic solvents, ketones and halogenated hydrocarbons are preferred, and methyl ethyl ketone and dichloromethane are more preferred.

[0143] <Aqueous medium> The aqueous medium used in this step may be water, or an aqueous medium containing water as the main component and optionally containing water-soluble solvents such as alcohols and glycols, surfactants, dispersants, etc. The aqueous medium used is preferably a mixture of water and surfactants.

[0144] Examples of surfactants include cationic surfactants, anionic surfactants, and nonionic surfactants. Examples of cationic surfactants include dodecyl ammonium chloride, dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, and hexadecyl trimethyl ammonium bromide. Examples of anionic surfactants include fatty acid soaps such as sodium stearate and sodium dodecanoate, sodium dodecyl benzene sulfonate, and sodium dodecyl sulfate. Examples of nonionic surfactants include polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene dodecyl ether, polyoxyethylene sorbitan monooleate ether, and monodecanoyl sucrose.

[0145] Such surfactants can be used alone or in combination of two or more. Among the surfactants, anionic surfactants are preferred, and sodium dodecylbenzenesulfonate is more preferred.

[0146] The amount of surfactant added is preferably 0.01 to 10 parts by mass, more preferably 0.04 to 1 part by mass, in terms of solid content, relative to 100 parts by mass of the aqueous medium.

[0147] (1C) Colorant particle dispersion preparation process This colorant particle dispersion preparation step is a step of dispersing a colorant in the form of fine particles in an aqueous medium to prepare a colorant particle dispersion.

[0148] The colorant can be dispersed using mechanical energy. The number-based median diameter of the colorant particles in the dispersion is preferably 10 to 300 nm, and more preferably 50 to 200 nm. The number-based median diameter of the colorant particles can be measured using an electrophoretic light scattering photometer "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.).

[0149] The steps from (2) association step to (6) external additive addition step can be carried out according to various conventionally known methods.

[0150] The flocculant used in the (2) association step is not particularly limited, but is preferably selected from metal salts. Examples of metal salts include monovalent metal salts such as salts of alkali metals such as sodium, potassium, and lithium; divalent metal salts such as calcium, magnesium, manganese, and copper; and trivalent metal salts such as iron and aluminum. Specific metal salts include sodium chloride, potassium chloride, lithium chloride, calcium chloride, magnesium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Among these, divalent metal salts are particularly preferred because they can promote flocculation in smaller amounts. These can be used alone or in combination of two or more.

[0151] [Developer] The toner according to the present invention can be suitably used in various cases, including when it contains a magnetic material and is used as a one-component magnetic toner, when it is mixed with a so-called carrier and is used as a two-component developer, or when it is used alone as a non-magnetic toner.

[0152] As the magnetic material, for example, magnetite, γ-hematite, or various ferrites can be used.

[0153] The carrier contained in the two-component developer may be magnetic particles made of conventionally known materials such as metals such as iron, steel, nickel, cobalt, ferrite, and magnetite, and alloys of these metals with metals such as aluminum and lead.

[0154] The carrier may be a coated carrier in which the surface of magnetic particles is coated with a coating agent such as a resin, or a resin-dispersed carrier in which magnetic powder is dispersed in a binder resin. The resin for coating is not particularly limited, but examples thereof include olefin resin, acrylic resin, styrene resin, styrene-acrylic resin, silicone resin, polyester resin, and fluororesin. The resin for constituting the resin-dispersed carrier particles is not particularly limited, and known resins can be used, such as acrylic resin, styrene-acrylic resin, polyester resin, fluororesin, and phenolic resin.

[0155] The volume-based median diameter of the carrier is preferably 20 to 100 μm, and more preferably 25 to 80 μm. The volume-based median diameter of the carrier can be measured typically by a laser diffraction particle size distribution analyzer "HELOS" (manufactured by SYMPATEC) equipped with a wet disperser.

[0156] The amount of toner mixed is preferably 2 to 10% by mass, with the total mass of toner and carrier being 100% by mass.

[0157] [Image forming method] The toner of the present invention can be used in various known electrophotographic image forming methods. For example, it can be used in monochrome image forming methods and full-color image forming methods. In the full-color image forming method, it can be applied to any image forming method, such as a four-cycle image forming method consisting of four color developing devices for yellow, magenta, cyan, and black, and one photoconductor, or a tandem image forming method in which image forming units each having a color developing device and a photoconductor for each color are installed separately.

[0158] That is, an image forming method according to one embodiment of the present invention includes the steps of: 1) forming a toner image made of the toner of the present invention on a recording medium; and 2) irradiating the toner image with light to soften the toner image. This embodiment provides excellent fixability and high image quality.

[0159] Regarding step 1) In this step, a toner image made of the toner of the present invention is formed on a recording medium.

[0160] (Recording medium) The recording medium is a member for holding a toner image. Examples of the recording medium include coated printing paper such as plain paper, high-quality paper, art paper, and coated paper, commercially available Japanese paper and postcards, resin films for overhead projectors or packaging materials, and cloth.

[0161] The recording medium may be in the form of a sheet (foliage) having a predetermined size, or may be in the form of a long sheet that is wound up into a roll after the toner image is fixed thereon.

[0162] As will be described later, the toner image can be formed by, for example, transferring the toner image on the photosensitive member onto a recording medium.

[0163] Regarding step 2) In this process, the formed toner image is irradiated with light to soften the toner image, thereby allowing the toner image to adhere to the recording medium.

[0164] The wavelength of the irradiated light is not particularly limited as long as it can sufficiently soften the toner image by photothermal conversion by the compound in the toner, but is preferably 280 nm or more and 480 nm or less. If it is in this range, the toner image can be softened more efficiently. From the same viewpoint, the amount of light irradiation is preferably 0.1 to 200 J / cm. 2 , more preferably 0.1 to 100 J / cm 2 , and more preferably 0.1 to 50 J / cm 2 is.

[0165] As will be described later, the light irradiation can be carried out using a light source such as a light emitting diode (LED) or a laser light source. Furthermore, as will be described later, heating may be further carried out in addition to the light irradiation.

[0166] After step 2), if necessary, step 3) of applying pressure to the softened toner image may be further carried out. This embodiment improves fixability.

[0167] Regarding step 3) In this step, the softened toner image is pressed.

[0168] The pressure when pressing the toner image on the recording medium is not particularly limited, but is preferably 0.01 to 5.0 MPa, and more preferably 0.05 to 1.0 MPa. By setting the pressure to 0.01 MPa or more, the amount of deformation of the toner image can be increased, which increases the contact area between the toner image and the recording paper S and makes it easier to further improve the fixability of the image. In addition, by setting the pressure to 5.0 MPa or less, shock noise during pressure application can be suppressed.

[0169] The pressure application step may be carried out before or simultaneously with the step of irradiating the toner image with light to soften it (step 2) described above), but it is preferable to carry it out after the light application step, since this allows pressure to be applied to the toner image that has already been softened, thereby further improving the fixability of the image.

[0170] Furthermore, in the pressurizing step, the softened toner image may be further heated. That is, the pressurizing step may be performed while heating the toner image. The temperature at this time (for example, the temperature of the pressure member) is preferably 15°C or higher, more preferably 20°C or higher, even more preferably more than 20°C, even more preferably 30°C or higher, and even more preferably 40°C or higher. In such an embodiment, fixability is significantly improved. There is no particular upper limit, but it is, for example, 200°C or lower, 150°C or lower, or 100°C or lower.

[0171] The heating temperature of the toner image (the surface temperature of the toner image during heating) is preferably (Tg + 20) to (Tg + 100)°C, and more preferably (Tg + 25) to (Tg + 80)°C, where Tg is the glass transition temperature of the toner. If the surface temperature of the toner image is (Tg + 20)°C or higher, the toner image is easily deformed by pressure, and if it is (Tg + 100)°C or lower, hot offset is easily suppressed. Hot offset refers to a phenomenon in which part of the toner is transferred to a pressure member such as a roller during the fixing process, causing the toner layer to separate.

[0172] Furthermore, before step 2), step 4) of preheating the toner image may be further carried out as needed. By further carrying out step 4) of preheating the toner image before step 2), the light sensitivity of the compound of the present invention can be further increased. This makes it difficult for the light sensitivity to be lost even though the compound is a polymer, and therefore facilitates the melting or softening of the toner image by light irradiation.

[0173] The image forming method of the present invention can be carried out by using, for example, the following image forming apparatus.

[0174] Fig. 1 is a schematic diagram showing an image forming apparatus 100 used in an image forming method according to one embodiment of the present invention. However, the image forming apparatus used in the present invention is not limited to the following form and illustrated example. Fig. 1 shows an example of a monochrome image forming apparatus 100, but the present invention can also be applied to a color image forming apparatus.

[0175] The image forming device 100 is an apparatus for forming an image on a recording sheet S as a recording medium, and is equipped with an image reading device 71 and an automatic document feeder 72, and forms an image on the recording sheet S transported by a paper transport system 7 using an image forming unit 10, an irradiation unit 40, and a pressing unit 9.

[0176] Furthermore, although the image forming apparatus 100 uses recording paper S as a recording medium, the medium on which an image is formed may be something other than paper.

[0177] An original d placed on the platen of the automatic document feeder 72 is scanned and exposed by the optical system of the scanning exposure device of the image reading device 71 and read into the image sensor CCD. The analog signal photoelectrically converted by the image sensor CCD is subjected to analog processing, A / D conversion, shading correction, image compression processing, etc. in the image processing unit 20, and then input to the exposure unit 3 of the image forming unit 10.

[0178] The paper transport system 7 includes a plurality of trays 16, a plurality of paper feed units 11, transport rollers 12, a transport belt 13, etc. The trays 16 each store recording paper S of a predetermined size, and operate the paper feed unit 11 of the specified tray 16 in response to an instruction from the control unit 90 to supply the recording paper S. The transport rollers 12 transport the recording paper S sent from the tray 16 by the paper feed unit 11 or the recording paper S brought in from the manual paper feed unit 15 to the image forming unit 10.

[0179] The image forming unit 10 is configured by arranging a charger 2, an exposure unit 3, a developing unit 4, a transfer unit 5, and a cleaning unit 8 in this order around the photoreceptor 1 along the direction of rotation of the photoreceptor 1.

[0180] The photoreceptor 1, which is an image carrier, has a photoconductive layer formed on its surface and is configured to be rotatable in the direction of the arrow in Fig. 1 by a drive device (not shown). A thermo-hygrometer 17 is provided near the photoreceptor 1 to detect the temperature and humidity inside the image forming apparatus 100.

[0181] The charger 2 uniformly charges the surface of the photoreceptor 1, thereby uniformly charging the surface of the photoreceptor 1. The exposure unit 3 is equipped with a beam emitting source such as a laser diode, and irradiates the charged surface of the photoreceptor 1 with a beam of light, thereby dissipating the charge in the irradiated area and forming an electrostatic latent image on the photoreceptor 1 according to the image data. The development unit 4 supplies the toner stored therein to the photoreceptor 1, and creates a toner image on the surface of the photoreceptor 1 based on the electrostatic latent image.

[0182] The transfer unit 5 faces the photoreceptor 1 across the recording paper S, and transfers the toner image onto the recording paper S. The cleaning unit 8 includes a blade 85. The blade 85 cleans the surface of the photoreceptor 1 to remove any developer remaining on the surface of the photoreceptor 1.

[0183] The recording paper S onto which the toner image has been transferred is transported by a transport belt 13 to a pressing unit 9. The pressing unit 9 is an optional unit that performs a fixing process on the recording paper S onto which the toner image has been transferred by applying pressure alone or heat and pressure with pressure members 91 and 92, thereby fixing the image onto the recording paper S. The recording paper S onto which the image has been fixed is transported by a transport roller to a paper discharge unit 14, and is discharged from the paper discharge unit 14 to the outside of the machine.

[0184] The image forming apparatus 100 also includes a paper inversion section 24, which transports the recording paper S that has been subjected to the heat fixing process to the paper inversion section 24 before the paper discharge section 14, where it is either inverted and discharged, or transports the inverted recording paper S back to the image forming section 10, where images can be formed on both sides of the recording paper S.

[0185] <Irradiation unit> FIG. 2 is a schematic diagram of the irradiation unit 40 in the image forming apparatus 100. As shown in FIG.

[0186] An image forming apparatus 100 according to one embodiment of the present invention includes an irradiation unit 40. The irradiation unit 40 includes a light source 41 and a heating member 93. Examples of devices that constitute the light source 41 include a light emitting diode (LED) and a laser light source.

[0187] The light source 41 irradiates the toner image formed on the recording medium with light to soften the toner image. The conditions for light irradiation are not particularly limited as long as they melt and fluidize the compound of the present invention contained in the toner of the developer. The wavelength of the light irradiated onto the toner image may be sufficient to sufficiently fluidize the compound, and is preferably in the range of 280 nm to 480 nm, more preferably in the range of 300 nm to 420 nm, and even more preferably in the range of 330 nm to 420 nm. The amount of light irradiated by the light source 41 may also be sufficient to sufficiently fluidize the compound, and is, for example, 0.1 J / cm. 2 More than 200J / cm 2 Within the following range, preferably 0.1 J / cm 2 More than 100J / cm 2 Within the range of 0.1 J / cm 2 More than 50J / cm 2 It is within the following range:

[0188] When the toner image is softened by irradiating it with light from the light source 41, the toner image may be heated by the heating member 93 in addition to the light irradiation. This allows the toner image to be softened and melted more efficiently. The heating temperature at this time is, for example, in the range of 20°C to 200°C, and preferably in the range of 20°C to 150°C.

[0189] The softened toner image can be solidified and fixed to the recording medium by leaving it at room temperature (within a range of 25±15°C), heating it, or irradiating it with visible light. As will be described later, the fixing step preferably further includes a step of applying pressure to the softened toner image. In the pressurizing step, it is preferable to further heat the softened toner image.

[0190] Light source 41 irradiates light toward a first surface of recording paper S that holds a toner image, the first surface being the photoreceptor side, and is disposed on the photoreceptor side relative to the surface of recording paper S that is nipped between photoreceptor 1 and transfer roller 5, which is a transfer section. Heating member 93 is disposed on the opposite side of light source 41 relative to the surface of recording paper S. Light source 41 and heating member 93 are disposed along the transport direction of recording paper S (paper transport direction).

[0191] The light source 41 and the heating member 93 are disposed downstream of the nip position between the photosensitive member 1 and the transfer roller 5 in the paper transport direction and upstream of the pressure bonding unit 9 in the paper transport direction.

[0192] According to an image forming method according to one embodiment of the present invention, photoconductor 1 is charged by applying a uniform potential to it using charger 2, and then a light beam emitted by exposure unit 3 is scanned onto photoconductor 1 based on original image data to form an electrostatic latent image. Next, developing unit 4 supplies a developer containing the toner of the present invention onto photoconductor 1.

[0193] When the recording paper S is transported from the tray 16 to the image forming unit 10 at the timing when the toner image carried on the surface of the photosensitive member 1 reaches the position of the transfer unit 5 due to the rotation of the photosensitive member 1, the toner image on the photosensitive member 1 is transferred onto the recording paper S nipped between the transfer unit 5 and the photosensitive member 1 by the transfer bias applied to the transfer unit 5.

[0194] In addition, the transfer unit 5 also serves as a pressure member, and can transfer the toner image from the photoreceptor 1 to the recording paper S while reliably bringing the compound contained in the toner image into close contact with the recording paper S.

[0195] After the toner image is transferred onto the recording paper S, the blade 85 of the cleaning unit 8 removes the developer remaining on the surface of the photoreceptor 1.

[0196] During the process in which the recording paper S onto which the toner image has been transferred is transported by the transport belt 13 to the pressing unit 9, the light source 41 irradiates the toner image transferred onto the recording paper S with light. By irradiating the toner image on the first side of the recording paper S with light from the light source 41, the toner image can be melted more reliably, and the fixability of the toner image to the recording paper S can be improved.

[0197] When the recording paper S carrying the toner image reaches the pressing unit 9 via the conveyor belt 13, pressure members 91 and 92 press the toner image onto the first side of the recording paper S. Before the toner image is fixed by the pressing unit 9, the toner image is softened by light irradiation from the light source 41, which makes it possible to save energy in pressing the image onto the recording paper S. Furthermore, in the process of solidifying the toner image and fixing it to the recording medium, the toner image is pressed by the pressure members 91 and 92, which further improves the fixability of the toner image onto the recording paper S.

[0198] The pressure to be applied when pressing the toner image is as described above. The pressing step may be performed before, simultaneously with, or after the step of softening the toner image by irradiating it with light. From the viewpoint of being able to apply pressure to a toner image in a softened state in advance and facilitating increasing the image strength, it is preferable to perform the pressing step after the light irradiation.

[0199] Furthermore, the pressure member 91 can heat the toner image on the recording paper S when the recording paper S passes between the pressure members 91 and 92. The toner image softened by the light irradiation is further softened by this heating, and as a result, the fixability of the toner image to the recording paper S is further improved.

[0200] The heating temperature of the toner image is as described above. The heating temperature of the toner image (surface temperature of the toner image) can be measured by a non-contact temperature sensor. Specifically, for example, a non-contact temperature sensor may be installed at a position where the recording medium is ejected from the pressure member, and the surface temperature of the toner image on the recording medium may be measured.

[0201] The toner image pressed by the pressure members 91 and 92 is solidified and fixed onto the recording paper S.

[0202] In one embodiment of the present invention, the fixing device has a pressing unit equipped with a pressure member.

[0203] In one embodiment of the present invention, the pressure member has a heating means.

[0204] In one embodiment of the present invention, the temperature of the pressure member is preferably 15° C. or higher, more preferably 20° C. or higher, even more preferably more than 20° C., even more preferably 30° C. or higher, and even more preferably 40° C. or higher. There is no particular upper limit, but it is, for example, 200° C. or lower, 150° C. or lower, or 100° C. or lower.

[0205] <Photoresponsive adhesive> The compound of the present invention becomes fluid upon irradiation with light and reversibly becomes non-fluid, so that a photoresponsive adhesive (photosensitive adhesive) that can be used repeatedly can be produced using the compound of the present invention. For example, in response to changes in viscosity (coefficient of friction), the compound can be applied to various adhesive technologies as a photoresponsive adhesive that can be repeatedly photo-attached and detached. That is, one embodiment of the present invention is a photoresponsive adhesive that includes the compound of the present invention.

[0206] The light-responsive adhesive of the present invention can be used for repeated temporary fastening and is also suitable for recycling, but is not limited to these uses.

[0207] <Photoswitching materials> Because the compound of the present invention fluidizes and reversibly becomes non-fluid upon light irradiation, a photoswitchable material can be prepared using the compound of the present invention. For example, photoswitchable materials can be prepared by utilizing changes in color or polarity, mass transfer, orientation, viscosity, and surface tension that occur with photoisomerization. For example, in liquid crystal materials, the compound can be applied to patterning that allows repeated rewriting in response to changes in molecular orientation that occur with photoisomerization. Furthermore, for example, changes in surface tension that occur with light irradiation and the resulting mass transfer can be utilized to perform microfabrication of the surface of a polymer film. That is, one embodiment of the present invention is a photoswitchable material that includes the compound of the present invention.

[0208] The optical switching material of the present invention can be used for liquid crystal display materials and surface processing of polymer films, but is not limited thereto. [Example]

[0209] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0210] Example 1: Synthesis of Compound 1 4-Hexyloxy-2,6-dimethylbenzaldehyde (5 mmol), 1-methyl-1H-pyrazol-4-amine (5 mmol), and 20 ml of ethanol were added to a 100 ml four-neck flask equipped with a condenser, nitrogen inlet, and thermometer, and the mixture was heated and stirred. The reaction solution was suction filtered, and the resulting powder was washed with cooled ethanol. The product was then recrystallized from heptane to give the target compound 1 in a 61% yield.

[0211] [ka]

[0212] 1 The formation of compound 1 was confirmed by 1 H NMR. 1H NMR (400MHz, CDCl3); 8.85ppm(s,1H,pyrazol), 8.39ppm(s,1H,CH=N), 8.02ppm(s,1H,pyrazol), 6.83ppm(s,1H,aryl), 4.11ppm(t,2H,meth ylene), 3.95ppm(s,3H,methyl), 2.31ppm(s,6H,methyl), 1.81ppm(m,2H,methylene), 1.26ppm(m,6H,methylene), 0.89ppm(t,3H,methyl).

[0213] <Examples 2 to 14 and Comparative Examples 1 to 7: Synthesis of Compounds 2 to 14 and Comparative Compounds 1 to 7> The synthesis of compounds 2 to 14 and comparative compounds 1 to 7 was carried out in the same manner as in the synthesis of compound 1, except that 4-hexyloxy-2,6-dimethylbenzaldehyde and 1-methyl-1H-pyrazol-4-amine were replaced with the corresponding raw materials shown below, and the target compounds were obtained. 1 The formation of each compound was confirmed by 1 H NMR.

[0214] Synthesis of compound 2: 4-hexyloxy-2,6-dimethylbenzaldehyde and 1-hexyl-1H-pyrazol-4-amine; Synthesis of compound 3: 4-hexyloxy-2,6-diethylbenzaldehyde, 1-methyl-1H-pyrazol-4-amine; Synthesis of compound 4: 4-hexyloxy-2,6-dipropylbenzaldehyde, 1-methyl-1H-pyrazol-4-amine; Synthesis of compound 5: 4-hexyloxy-2,6-dimethoxybenzaldehyde, 1-methyl-1H-pyrazol-4-amine; Synthesis of compound 6: 4-hexyloxy-2,6-difluorobenzaldehyde, 1-methyl-1H-pyrazol-4-amine; Synthesis of compound 7: 4-decyloxy-2,6-dimethylbenzaldehyde, 1-methyl-1H-pyrrol-3-amine; Synthesis of compound 8: 4-hexyloxy-2,6-dimethylaniline, 1-hexyl-1H-pyrrole-3-carboxaldehyde; Synthesis of compound 9: 4-hexyloxy-2,6-dimethylbenzaldehyde, 1-methyl-1H-pyrrol-2-amine; Synthesis of compound 10: 4-hexyloxy-2,6-dimethylbenzaldehyde, 1H-indol-6-amine; Synthesis of compound 11: 4-hexyloxy-2,6-dimethylbenzaldehyde, 1-methyl-1H-pyrazol-3-amine; Synthesis of compound 12: 4-decyloxy-2,6-dimethylbenzaldehyde, 2-aminoimidazole; Synthesis of compound 13: 4-decyloxy-2,6-dimethylbenzaldehyde, 2-amino-5-hexylthiophene; Synthesis of compound 14: 4-hexyloxy-2,6-dimethylaniline, 5-methylthiophene-2-carboxaldehyde; Synthesis of comparative compound 1 (Comparative 1): 4-hexyloxy-2-methylbenzaldehyde, 1-hexyl-1H-pyrazol-4-amine; Synthesis of comparative compound 2 (Comparative 2): 4-hexyloxy-2,5-dimethylbenzaldehyde, 1-methyl-1H-pyrazol-4-amine; Synthesis of comparative compound 3 (Comparative 3): 4-hexyloxy-2-fluorobenzaldehyde, 1-ethyl-1H-pyrazol-4-amine: Synthesis of comparative compound 4 (Comparative 4): 4-hexyloxy-2,5-dimethylamine, 1-methyl-1H-pyrazole-4-carboxaldehyde; Synthesis of comparative compound 5 (Comparative 5): 4-hexyloxy-2-fluoroamine, 1-methyl-1H-pyrazole-4-carboxaldehyde; Synthesis of comparative compound 6 (Comparative 6): 4-hexyloxy-2-methoxyamine, 1-methyl-1H-pyrazole-4-carboxaldehyde; Synthesis of comparative compound 7 (Comparative 7): 4-hexyloxy-benzaldehyde, 1-methyl-1H-pyrrol-3-amine.

[0215] The structures of compounds 1 to 14 and comparative compounds 1 to 7 are shown in Table 1 below.

[0216] <Comparative Example 8: Synthesis of Comparative Compound 8> The following comparative compound 8 (comparative 8, number average molecular weight Mn: 2870) was obtained by the method described in paragraphs 0217 to 0227 of JP 2014-191078 A.

[0217] [ka]

[0218] [Toner production] (Preparation of Toner 1) <Preparation of styrene acrylic resin particle dispersion 1> (First stage polymerization) A reaction vessel equipped with a stirrer, temperature sensor, cooling tube, and nitrogen inlet device was charged with a solution of 8 parts by weight of sodium dodecyl sulfate dissolved in 3,000 parts by weight of ion-exchanged water, and the mixture was stirred at a stirring speed of 230 rpm under a nitrogen stream while the internal temperature was raised to 80 ° C. After the temperature was raised, a solution of 10 parts by weight of potassium persulfate dissolved in 200 parts by weight of ion-exchanged water was added, the liquid temperature was again raised to 80 ° C., and a polymerizable monomer solution consisting of 480 parts by weight of styrene, 250 parts by weight of n-butyl acrylate, 68.0 parts by weight of methacrylic acid, and 16.0 parts by weight of n-octyl-3-mercaptopropionate was added dropwise over 1 hour, and the mixture was heated to 80 ° C. for 2 hours with stirring to polymerize, thereby preparing a styrene-acrylic resin particle dispersion (1A) containing styrene-acrylic resin particles (1a).

[0219] (Second stage polymerization) A solution of 7 parts by weight of sodium polyoxyethylene (2) dodecyl ether sulfate dissolved in 800 parts by weight of ion-exchanged water was placed in a reaction vessel equipped with a stirrer, temperature sensor, cooling tube, and nitrogen supply device, and heated to 98°C. After heating, a polymerizable monomer solution prepared by dissolving 260 parts by weight of the styrene-acrylic resin particle dispersion (1A) obtained above, 245 parts by weight of styrene, 120 parts by weight of n-butyl acrylate, 1.5 parts by weight of n-octyl-3-mercaptopropionate, and 67 parts by weight of the release agent paraffin wax "HNP-11" (manufactured by Nippon Seiro Co., Ltd.) at 90°C was added, and the mixture was mixed and dispersed for 1 hour using a mechanical disperser "CREARMIX (registered trademark)" (manufactured by M-Technique Co., Ltd.) with a circulation path to prepare a dispersion containing emulsified particles (oil droplets). Next, an initiator solution prepared by dissolving 6 parts by mass of potassium persulfate in 200 parts by mass of ion-exchanged water was added to this dispersion, and the system was heated and stirred at 82°C for 1 hour to carry out polymerization, thereby preparing a styrene-acrylic resin particle dispersion (1B) containing styrene-acrylic resin particles (1b).

[0220] (Third stage polymerization) A solution of 11 parts by weight of potassium persulfate dissolved in 400 parts by weight of ion-exchanged water was added to the resulting styrene-acrylic resin particle dispersion (1B). Then, at a temperature of 82°C, a polymerizable monomer solution consisting of 435 parts by weight of styrene, 130 parts by weight of n-butyl acrylate, 33 parts by weight of methacrylic acid, and 8 parts by weight of n-octyl-3-mercaptopropionate was added dropwise over one hour. After the addition was complete, the mixture was heated and stirred for two hours to polymerize, and then cooled to 28°C to obtain styrene-acrylic resin particle dispersion 1 containing styrene-acrylic resin 1. The glass transition temperature (Tg) of styrene-acrylic resin 1 was measured and found to be 45°C.

[0221] <Preparation of azomethine compound particle dispersion 1> 80 parts by mass of dichloromethane and 20 parts by mass of compound 1 prepared above were mixed and stirred while heating at 50°C to obtain a liquid containing compound 1. To 100 parts by mass of this liquid, a mixed liquid of 99.5 parts by mass of distilled water heated to 50°C and 0.5 parts by mass of a 20% by mass aqueous solution of sodium dodecylbenzenesulfonate was added. The mixture was then emulsified by stirring at 16,000 rpm for 20 minutes using a homogenizer (manufactured by Heidolph) equipped with a shaft generator 18F, to obtain emulsion 1 of the azomethine compound.

[0222] The resulting azomethine compound emulsion 1 was placed in a separable flask, and the organic solvent was removed by heating and stirring at 40° C. for 90 minutes while nitrogen was blown into the gas phase, to obtain azomethine compound particle dispersion 1.

[0223] (Preparation of Black Colorant Particle Dispersion (Bk-1)) A black colorant particle dispersion (Bk-1) was prepared by dissolving 11.5 parts by weight of sodium n-dodecyl sulfate in 160 parts by weight of pure water, gradually adding 25 parts by weight of carbon black "Mogul L (Cabot Corporation)," and then dispersing using "Clearmix® W Motion CLM-0.8 (M Technique Co., Ltd.)." The volume-based median diameter of the colorant particles in the black colorant particle dispersion (Bk-1) was 110 nm.

[0224] (aggregation, fusion) 504 parts by mass (solids content) of the styrene acrylic resin particle dispersion 1 prepared above, 216 parts by mass (solids content) of the azomethine compound particle dispersion 1, 900 parts by mass of ion-exchanged water, and 70 parts by mass (solids content) of the black colorant particle dispersion were charged into a reactor equipped with a stirrer, a temperature sensor, and a cooling tube. The temperature inside the vessel was maintained at 30°C, and a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 10.

[0225] Next, an aqueous solution containing 2 parts by weight of magnesium chloride hexahydrate dissolved in 1,000 parts by weight of ion-exchanged water was added dropwise over 10 minutes while stirring. The temperature was then raised to 70°C over 60 minutes, and the particle growth reaction continued while maintaining the temperature at 70°C. The particle size of the aggregated particles was measured using a Multisizer 3 (Beckman Coulter, Inc.). When the volume-based median diameter (D50) reached 6.5 μm, an aqueous solution containing 190 parts by weight of sodium chloride dissolved in 760 parts by weight of ion-exchanged water was added to terminate particle growth. After stirring at 70°C for 1 hour, the temperature was further raised and the particles were heated and stirred at 75°C to promote particle fusion. The mixture was then cooled to 30°C, yielding a dispersion of toner base particles.

[0226] The dispersion of the toner base particles obtained above was subjected to solid-liquid separation using a centrifuge to form a wet cake of the toner base particles. The wet cake was washed with ion-exchanged water at 35°C until the electrical conductivity of the filtrate from the centrifuge reached 5 μS / cm, and then transferred to a "Flash Jet Dryer (manufactured by Seishin Enterprise Co., Ltd.)" and dried until the moisture content reached 0.5% by mass, thereby producing toner base particles.

[0227] To 100% by mass of the obtained toner base particles, 1% by mass of hydrophobic silica (number average primary particle size: 12 nm) and 0.3% by mass of hydrophobic titania (number average primary particle size: 20 nm) were added and mixed using a Henschel mixer (registered trademark), thereby obtaining toner 1.

[0228] (Preparation of Toners 2 to 18 and Comparative Examples 1 to 8) Toners 2 to 14 and the toners of Comparative Examples 1 to 8 were each produced in the same manner as in the production of Toner 1, except that in the production of Toner 1, Compound 1 was changed to Compounds 2 to 14 and the compounds of Comparative Examples 1 to 8. Furthermore, in the production of Toner 1, Toners 15 to 18 were each produced in the same manner as in the production of Toner 1, except that the mass ratio of Compound 1 to the styrene acrylic resin was changed as shown in Table 3 below.

[0229] (Production of Toner 19) Toner 19 was prepared in the same manner as in the preparation of Toner 1 above, except that in the (aggregation and fusion) step in the preparation of Toner 1, styrene acrylic resin particle dispersion 1 (504 parts by mass in terms of solid content) was changed to polyester resin particle dispersion 2 (504 parts by mass in terms of solid content) prepared as follows.

[0230] <Preparation of Polyester Resin Particle Dispersion 2 Containing Polyester Resin 1) A 10-liter four-neck flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was charged with 524 parts by weight of bisphenol A propylene oxide 2-mol adduct, 105 parts by weight of terephthalic acid, 69 parts by weight of fumaric acid, and 2 parts by weight of tin octoate (esterification catalyst), and a polycondensation reaction was carried out at 230°C for 8 hours. The polycondensation reaction was continued for another hour at 8 kPa and then cooled to 160°C to obtain polyester resin 1. One hundred parts by weight of polyester resin 1 was pulverized using a Randel Mill (Model: RM) (manufactured by Tokuju Manufacturing Co., Ltd.) and mixed with 638 parts by weight of a previously prepared 0.26% by weight aqueous solution of sodium lauryl sulfate. While stirring, the mixture was ultrasonically dispersed for 30 minutes at V-LEVEL and 300 μA using an ultrasonic homogenizer (manufactured by Nippon Seiki Mfg. Co., Ltd.) to obtain polyester resin particle dispersion 2. The glass transition temperature Tg of this polyester resin 1 was measured and found to be 42°C.

[0231] (Preparation of developer) Ferrite carrier particles with a volume average particle size of 30 μm coated with a copolymer resin of cyclohexane methacrylate and methyl methacrylate (monomer mass ratio 1:1) were mixed with the toners 1 to 19 and the toners of Comparative Examples 1 to 8 prepared above so that the toner particle concentration was 6 mass %, thereby obtaining developers 1 to 19 and the developers of Comparative Examples 1 to 8. Mixing was carried out for 30 minutes using a V-type mixer.

[0232] [Evaluation: Photoresponsive adhesion test of compounds] The change in adhesiveness of Compounds 1 to 14 and Comparative Compounds 1 to 8 prepared in each Example upon light irradiation was evaluated by the following photoresponsive adhesion test using the apparatus shown in Figure 3. As shown in Figure 3, 4 mg of compound was placed on an 18 mm square cover glass 1 within a 6 mm radius from the center of the glass, and a cover glass 2 of the same size was placed on top of the cover glass 1, offset approximately 4 mm in a parallel direction, so as to completely cover the compound. This was heated to melt the sample and bond the cover glass 1 and cover glass 2 together. Each of the obtained samples was subjected to the following non-fluidity to fluidity test, and then the following fluidity to non-fluidity (reversion) test.

[0233] <Testing non-liquidity → liquidity> Part (A) shown in Figure 3 was fixed to the table with cellophane tape, and part (C) was fixed with cellophane tape to a 30 cm long vinyl string with a 150 g weight attached. Part (B) was irradiated with 365 nm light at a dose of 18 J / cm. 2 It was confirmed whether cover glass 2 peeled off from cover glass 1, and the results were evaluated according to the following evaluation criteria. The results are shown in Table 2 below.

[0234] -Evaluation criteria for non-liquidity to liquidity testing- ◎: Cover glass 2 was completely peeled off from cover glass 1 ○: Cover glass 2 and cover glass 1 are misaligned ×: The cover glass 2 did not move.

[0235] <Test for liquidity → non-liquidity (return)> After the non-fluidity → fluidity test was completed, the following experiment was performed on samples in which cover glass 2 had completely peeled off and samples in which it had shifted. For samples that had shifted, cover glasses 1 and 2 were peeled off by hand. Ten minutes after the light irradiation for the non-fluidity → fluidity test had finished (the 10 minutes were left in a natural environment, i.e., a dark room at room temperature), cover glass 3 (the same size as cover glasses 1 and 2) was placed over the sample portion (part B) of cover glass 1 used in the above test, and it was confirmed whether cover glass 1 and cover glass 3 were adhered, and the adhesion was evaluated according to the following evaluation criteria. The results are shown in Table 2 below.

[0236] -Evaluation criteria for liquidity to non-liquidity (return) testing- ◎: Not adhered (non-fluidized) 〇: Partially adhered (partially maintained in a fluid state) ×: Adhesion was achieved (fluidized state was maintained).

[0237] [Evaluation: Fixation test] The fixing property test was carried out using the developers of the Examples and Comparative Examples obtained above under a normal temperature and humidity environment (temperature 20°C, relative humidity 50% RH). Specifically, the developer was placed on one side and CF paper (basis weight: 80 g / m) on the other side. 2 The developer is placed between a pair of parallel flat plate (aluminum) electrodes with magnetic force, and the gap between the electrodes is 0.5 mm. The DC bias and AC bias are used to control the toner adhesion amount to 6 g / m. 2 The toner was developed under the conditions shown above to form a toner layer on the surface of the CF paper, and the toner layer was fixed using each of the fixing devices described below to obtain a printed matter (image formation).

[0238] A 1cm square image on this printed matter was rubbed 20 times with a "JK Wiper (registered trademark)" (manufactured by Nippon Paper Crecia Co., Ltd.) at a pressure of 30 kPa, and the image fixation rate was evaluated. A fixation rate of 60% or higher was considered acceptable. The image fixation rate was measured using a reflection densitometer "RD-918" (manufactured by Sakata Inx Engineering Co., Ltd.) to measure the density of the image after printing and after rubbing, and the reflection density of the solid image after rubbing was divided by the reflection density of the solid image after printing, expressed as a percentage. The results are shown in Table 3 below.

[0239] The fixing devices used were the following four types of fixing devices configured by appropriately modifying the device shown in FIG. 2: No. 1: The pressure bonding portion 9 in FIG. 2 was not present, the temperature of the heating member 93 was 20°C, the wavelength of the ultraviolet light emitted from the light source 41 was 365 nm (light source: LED light source with an emission wavelength of 365 nm ± 10 nm), and the irradiation dose was 11 J / cm 2 is; No. 2: The pressure bonding unit 9 shown in FIG. 2 is included, the temperature of the heating member 93 is 20°C, the temperature of the pressure member 91 is 20°C, and the pressure during pressing is 0.2 MPa. The wavelength and irradiation amount of the light source 41 are the same as those of No. 1; No. 3: The pressure bonding unit 9 shown in FIG. 2 is included, the temperature of the heating member 93 is 20°C, the temperature of the pressure member 91 is 80°C, and the pressure during pressing is 0.2 MPa. The wavelength and irradiation amount of the light source 41 are the same as those of No. 1. No. 4: The pressure bonding portion 9 of FIG. 2 was not present, the temperature of the heating member 93 was 80° C., and the wavelength and irradiation amount of the light source 41 were the same as those of No. 1.

[0240] - Evaluation criteria for fixation - ◎: Retention rate is 85% or higher ○: Retention rate is between 80% and 85% △: Retention rate is between 60% and 80% ×: Retention rate is less than 60%.

[0241] [Evaluation of document offset resistance] Using the developers 1 to 19 obtained above and the developers of Comparative Examples 1 to 8, printed matter was produced in an environment of normal temperature and humidity (temperature 20°C, relative humidity 50% RH). The developer was placed on one side, and paper (CF paper, basis weight: 80 g / m) was placed on the other side as a recording medium. 2 The developer is placed between a pair of parallel flat plate (aluminum) electrodes with magnetic force, and the gap between the electrodes is 0.5 mm. The DC bias and AC bias are used to control the toner adhesion amount to 5 g / m. 2 The toner was developed under the conditions shown above, a toner layer was formed on the surface of the CF paper, and the toner was fixed in the No. 1 fixing device to obtain 10 printed sheets (image formation). The wavelength of the ultraviolet light irradiated from the irradiation unit 40 was 365 nm (light source: LED light source with an emission wavelength of 365 nm ± 10 nm), and the irradiation dose was 12 J / cm. 2 It was decided.

[0242] Next, the 10 printed sheets were placed on a marble table, and the overlapping parts were subjected to a pressure of 19.6 kPa (200 g / cm 2A weight was placed on the paper so that a pressure of 1000 kJ / cm was applied. After leaving the paper in this state for 3 days in an environment with a temperature of 30°C and a relative humidity of 60% RH, the overlapping prints were peeled off and the degree of image loss on the toner image and offset onto the non-image area on the back of the paper was evaluated for document offset resistance according to the following criteria. A rank of 4 or higher was considered to be acceptable. The evaluation results are shown in Table 3 below.

[0243] -Evaluation criteria for document offset resistance- 5: No image defects or image transitions are observed in either the image or non-image areas. 4: No image loss in the image area, but slight image transfer is observed in the non-image area on the back of the paper 3: There is almost no image loss in the image area and it is at an acceptable level, but some transfer is observed in the non-image area on the back of the paper. 2: There are white spots where the image is missing in places, and there is also some transfer to the non-image area on the back of the paper. 1: The fixed image in the image area peeled off, there was significant image loss, and the image clearly transferred to the non-image area on the back of the paper.

[0244] [Color reproducibility evaluation] The color reproducibility of the images of the Examples and Comparative Examples obtained in the above fixability test was evaluated by visual evaluation by 10 monitors according to the following evaluation criteria. Specifically, as a sample for evaluation comparison, a toner was prepared by removing the photoresponsive compound from the toner of each Example. Using this, a developer was prepared in the same manner as above, and development was carried out in the same manner as in the image formation in the above fixability test, followed by fixing using the following fixing device No. 5: Fixing device No. 5: The pressure bonding unit 9 in FIG. 2 was included, the temperature of the heating member 93 was 20° C., the temperature of the pressure member 91 was 150° C., the pressure during pressing was 0.2 MPa, and no light irradiation was performed.

[0245] Ten monitors were shown the sample for evaluation comparison and the sample described in the example in turn, and asked whether the colors of the two images were clearly different. The results of the evaluation based on the following color reproducibility evaluation criteria are shown in Table 3 below.

[0246] -Evaluation criteria for color reproducibility- ◎: Less than two people answered that it was clearly different ○: 3-4 people answered that there is a clear difference △: 5 to 7 people answered that there was a clear difference ×: Eight or more people answered that there was a clear difference.

[0247] [Table 1-1]

[0248] [Table 1-2]

[0249] [Table 2]

[0250] [Table 3-1]

[0251] [Table 3-2]

[0252] "Compound" in Table 3 refers to the compound of each example and comparative example. In Table 3, the ratios of compound and binder resin are the ratios (mass %) of compound and binder resin to the total amount of compound and binder resin in the toner.

[0253] From Table 2 above, it was found that compounds 1 to 14 of the examples, which have a specific structure represented by general formula (1), are fluidized by light irradiation and reversibly imfluidized. Furthermore, it was found that they fluidized more efficiently than the compounds of Comparative Examples 1 to 6, which do not have the specific structure. The compound of Comparative Example 7, which does not have the specific structure, was less likely to fluidize by light irradiation. Furthermore, the azobenzene compound of Comparative Example 8 was not observed to reversibly imfluidize after fluidization.

[0254] Furthermore, as shown in Table 3 above, all toners using the compounds prepared in each Example could be fixed by light irradiation, and exhibited high fixability, high image stability, and excellent color reproducibility. Furthermore, it was found that the toners using the compounds prepared in each Example had even higher fixability and image stability than those using the compounds of Comparative Examples 1 to 6 that did not have the above-mentioned specific structure. The toner using the polymer prepared in Comparative Example 7 had insufficient fixability and image stability. Furthermore, it was found that the toner using the azobenzene derivative of Comparative Example 8 had poor fixability and image stability, and poor color reproducibility.

[0255] Comparing the fixing devices, it was found that fixing device No. 2, which applied pressure with a pressure member, and fixing device No. 3, which applied pressure while heating with a pressure member, achieved higher fixability than fixing device No. 1, which was irradiated with ultraviolet light under the same conditions using the same toner 1 and no pressure member (comparison of Examples 1, 20, and 21).Furthermore, fixing device No. 4, which applied heating with heating member 93, achieved higher fixability than fixing device No. 1, which was irradiated with ultraviolet light under the same conditions and no heating was performed during ultraviolet light irradiation (comparison of Examples 1 and 22). [Explanation of symbols]

[0256] 1 photoreceptor, 2 chargers, 3 exposure device, 4 developing unit, 5 Transfer section (transfer roller), 7 Paper transport system, 8 cleaning section, 9 crimping part, 10 Image forming unit, 11 Paper feed section, 12 transport roller, 13 conveyor belt, 14 Paper output section, 15 Manual feed unit, 16 trays, 17 Thermohygrometer, 20 Image processing unit, 24 Paper reversing section, 40 irradiation unit, 41 light source, 71 Image reading device, 72 Automatic document feeder, 85 blades, 90 control section, 91, 92 pressure members, 93 heating element, 100 Image forming device, d manuscript, S Recording paper.

Claims

1. A compound represented by the following general formula (1), which becomes fluid upon irradiation with light and becomes reversibly non-fluid: 【Chemical 1】 During the ceremony, Z １ and Z ２ is CH or N, and Z １ ≠Z ２ and R １ Is Z １ and at two ortho positions relative to the group consisting of an alkyl group, an alkoxy group, and a halogen atom, R ａ and a phenyl group further having an alkoxy group having 4 to 18 carbon atoms at the para position relative to Z 1 ; R ２ is a substituted or unsubstituted aromatic heterocyclic group.

2. The R ａ is an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a halogen atom.

3. The R ２ In the aromatic heterocyclic group of the formula ２ 3. The compound according to claim 1, wherein a hydrogen atom is bonded to at least one carbon atom bonded adjacent to the carbon atom directly bonded to

4. The R ２ The compound according to any one of claims 1 to 3, which is represented by the following formula: 【Chemistry 2】 In the formula, R ｃ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms.

5. The compound according to any one of claims 1 to 4, wherein the wavelength of the light used for the irradiation is 280 nm or more and 480 nm or less.

6. A toner comprising the compound according to any one of claims 1 to 5.

7. The toner according to claim 6 , further comprising a binder resin.

8. The toner according to claim 7 , wherein the binder resin comprises at least one selected from the group consisting of a styrene-acrylic resin and a polyester resin.

9. forming a toner image on a recording medium, the toner being made of the toner according to any one of claims 6 to 8; irradiating the toner image with light to soften the toner image; An image forming method comprising:

10. 10. The image forming method according to claim 9, wherein the wavelength of the light is 280 nm or more and 480 nm or less.

11. 11. The image forming method according to claim 9, further comprising the step of pressing the toner image.

12. The image forming method according to claim 11, wherein the toner image is further heated in the pressurizing step.

13. 13. The image forming method according to claim 9, wherein in the step of irradiating the toner image with light to soften the toner image, the toner image is heated in addition to the light irradiation.

14. A light-responsive adhesive comprising the compound according to any one of claims 1 to 5.

15. A light-switching material comprising the compound according to any one of claims 1 to 5.

Images