Resin particles

Abstract

The present invention relates to resin particles which are resin particles containing a binder resin, a fluorescent colorant A, and a colorant B other than the fluorescent colorant A, wherein in the resin particles, there are a region RA where the content of the fluorescent colorant A is more than that of the colorant B, and a region RB where the content of the colorant B is more than that of the fluorescent colorant A.

Description

Technical Field

[0001] The present invention relates to resin particles. Background Art

[0002] Resin particles have various application purposes, and as one of them, toners in electrophotography can be cited. As existing toners, the toners described in Patent Documents 1 to 3 are well-known.

[0003] Patent Document 1 discloses a toner containing a binder resin and a colorant, characterized in that the colorant contains a coloring pigment and a fluorescent dye, and when the contents of the coloring pigment and the fluorescent dye in the toner are based on mass as W G 、W F respectively, the above W G and the above W F satisfy the following formula (1),

[0004] W G ×0.5 > W F > W G ×0.025 (1)

[0005] Let the absorption peak wavelength of the coloring pigment be P G 、Let the emission peak wavelength of the fluorescent dye be P F respectively, the above P G and the above P F satisfy the following formula (2).

[0006] P G < P F (2)

[0007] Patent Document 2 discloses a negatively charged magenta toner for electrophotography, characterized in that it is obtained by kneading a binder resin and, if necessary, other toner materials in a magenta-based colorant obtained by thermally kneading a rhodamine dye and a high acid value resin.

[0008] Patent Document 3 discloses a color toner, characterized in that it contains a mixed heat treatment product of a basic dye and a resin having an acid value of 5 to 120 as a colorant in a binder resin.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-3818

[0012] Patent Document 2: Japanese Patent Application Laid-Open No. 11-119742

[0013] Patent Document 3: Japanese Patent Laid-Open No. 54-5733 Summary of the Invention

[0014] Technical Problem to be Solved by the Invention

[0015] The technical problem to be solved by the present invention is to provide a resin particle, which has a higher fluorescence intensity of the obtained image compared with the case where there is no region RA in which the content of the fluorescent colorant A is more than that of the colorant B and region RB in which the content of the colorant B is more than that of the fluorescent colorant A in the resin particle containing a binder resin, a fluorescent colorant A, and a colorant B other than the fluorescent colorant A.

[0016] Means for Solving the Technical Problem

[0017] The specific means for solving the above technical problem include the following methods.

[0018] <1> A resin particle, which is a resin particle containing a binder resin, a fluorescent colorant A, and a colorant B other than the fluorescent colorant A, wherein there are a region RA in which the content of the fluorescent colorant A is more than that of the colorant B and a region RB in which the content of the colorant B is more than that of the fluorescent colorant A in the resin particle.

[0019] <2> The resin particle according to <1>, wherein in the resin particle, the region RA and the region RB form a sea-island structure or an interpenetrating network structure.

[0020] <3> The resin particle according to <2>, wherein in the resin particle, the region RA and the region RB form a sea-island structure.

[0021] <4> The resin particle according to <3>, wherein the region RA forms the island structure of the sea-island structure, and the region RB forms the sea structure of the sea-island structure.

[0022] <5> The resin particle according to <4>, wherein the ratio (VI / VT) of the volume average particle diameter VI of the island structure in the sea-island structure to the volume average particle diameter VT of the resin particle is 0.15 or more and 0.80 or less.

[0023] <6> The resin particle according to <5>, wherein the ratio (VI / VT) of the volume average particle diameter VI of the island structure in the sea-island structure to the volume average particle diameter VT of the resin particle is 0.30 or more and 0.65 or less.

[0024] <7> The resin particle according to any one of <1> to <6>, wherein the fluorescent colorant A is a fluorescent dye.

[0025] <8>The resin particles as described in <7>, wherein the fluorescent dye includes a fluorescent dye having a maximum fluorescence wavelength in the range of 580 nm to 650 nm.

[0026] <9>The resin particles as described in any one of <1> to <8>, wherein the colorant B includes a magenta pigment.

[0027] <10>The resin particles as described in <9>, wherein the colorant B includes two or more magenta pigments.

[0028] Advantages of the Invention

[0029] According to the solution of <1>, <8> or <9> above, there is provided a resin particle, compared with the case where in a resin particle containing a binder resin, a fluorescent colorant A, and a colorant B other than the fluorescent colorant A, there is no region RA where the content of the fluorescent colorant A is more than that of the colorant B and no region RB where the content of the colorant B is more than that of the fluorescent colorant A, the fluorescence intensity of the obtained image is high.

[0030] According to the solution of <2> above, there is provided a resin particle, compared with the case where the region RA and the region RB form a core-shell structure, the fluorescence intensity of the obtained image is higher.

[0031] According to the solution of <3> above, there is provided a resin particle, compared with the case where the region RA and the region RB form an interpenetrating network structure, the fluorescence intensity of the obtained image is higher.

[0032] According to the solution of <4> above, there is provided a resin particle, compared with the case where the sea structure of the above-mentioned sea-island structure is formed in the region RA and the island structure of the above-mentioned sea-island structure is formed in the region RB, the fluorescence intensity of the obtained image is higher.

[0033] According to the solution of <5> above, there is provided a resin particle, compared with the case where the ratio (VI / VT) of the volume average particle diameter VI of the island structure in the above-mentioned sea-island structure to the volume average particle diameter VT of the resin particle is less than 0.15 or greater than 0.80, the fluorescence intensity of the obtained image is higher.

[0034] According to the solution of <6> above, there is provided a resin particle, compared with the case where the ratio (VI / VT) of the volume average particle diameter VI of the island structure in the above-mentioned sea-island structure to the volume average particle diameter VT of the resin particle is less than 0.30 or greater than 0.65, the fluorescence intensity of the obtained image is higher.

[0035] According to the solution of <7> above, there is provided a resin particle, compared with the case where the fluorescent colorant A is a fluorescent pigment, the fluorescence intensity of the obtained image is higher.

[0036] According to the above-described <10> solution, a resin particle is provided, and the fluorescence intensity of the obtained image is higher than that in the case where the above-described colorant B contains only one magenta pigment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A cross-sectional schematic view showing an example of a toner image that is present.

[0038] Figure 2 A cross-sectional schematic view showing an example of a toner image formed by using the resin particles of the present embodiment as a toner for electrostatic image development.

[0039] Figure 3 A schematic configuration diagram showing the image forming apparatus used in the present embodiment.

[0040] Figure 4 A schematic configuration diagram showing the process cartridge used in the present embodiment.

[0041] Figure 5 An example of the spectrum (fluorescence spectrum) in each color of the fluorescent color is shown. The vertical axis represents the fluorescence intensity, and the horizontal axis represents the wavelength. Note that "mμ" = "nm". DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] In this specification, when referring to the amounts of the respective components in the composition, in the case where there are two or more substances corresponding to the respective components in the composition, unless otherwise specified, it means the total amount of the two or more substances present in the composition.

[0043] Hereinafter, an embodiment as an example of the present invention will be described.

[0044] <Resin Particles>

[0045] The resin particles of the present embodiment are resin particles containing a binder resin, a fluorescent colorant A, and a colorant B other than the above-described fluorescent colorant A, wherein in the above-described resin particles, there are a region RA where the content of the above-described fluorescent colorant A is higher than that of the above-described colorant B and a region RB where the content of the above-described colorant B is higher than that of the above-described fluorescent colorant A.

[0046] In recent years, in digital printing, various companies have launched printing machines for commercial printing, publishing, paper packaging, etc., as well as models that attract customers with spot color toners. Regarding fluorescent colors, most of them use color sample books or color cards such as the Neons Guide of PANTONE, the DIC Color Guide of DIC Corporation, or the COLORFINDER of Toyo Ink Co., Ltd. in the same way as ordinary spot colors, and select various colors from those with strong fluorescence to light ones. However, when it is desired to reproduce fluorescent colors using toners whose hues are adjusted by including fluorescent colorants and pigments, the fluorescence intensity may be lower than expected based on the amount of fluorescent pigments.

[0047] The present inventors conducted detailed research and found that in resin particles, when the fluorescent colorant A and the colorant B other than the above fluorescent colorant A are mixed in a nearly uniform state, the colorant B absorbs the light required for the fluorescence (excitation) of the fluorescent colorant A, thus weakening the fluorescence intensity.

[0048] The resin particles of the present embodiment adopt the above solution, and the fluorescence intensity of the obtained image is high. The reason is not yet certain, but it is speculated that it is due to the reasons shown below.

[0049] When there are regions RA where the content of the above fluorescent colorant A is higher than that of the colorant B and regions RB where the content of the colorant B is higher than that of the above fluorescent colorant A in the resin particles, light may only pass through and be reflected in the part where the fluorescent colorant A is present in a large amount. Therefore, a decrease in the fluorescence intensity of the fluorescent colorant A caused by the colorant B can be suppressed, and the fluorescence intensity of the obtained image is high.

[0050] The resin particles of the present embodiment will be described in detail below.

[0051] The resin particles contain a binder resin, a fluorescent colorant A, a colorant B other than the above fluorescent colorant A, and, if necessary, a release agent and other additives, and preferably contain a binder resin, a fluorescent colorant A, a colorant B other than the above fluorescent colorant A, and a release agent.

[0052] In addition, there are regions RA where the content of the above fluorescent colorant A is higher than that of the colorant B and regions RB where the content of the colorant B is higher than that of the above fluorescent colorant A in the above resin particles.

[0053] Figure 1 It is a cross-sectional schematic diagram showing an example of a toner image.

[0054] In a toner image formed using a toner containing a fluorescent colorant and a colorant other than the above fluorescent colorant, the toner image 52 formed on the recording medium 50 becomes a mixed color region 58 in which the fluorescent colorant and the colorant other than the above fluorescent colorant are mixed in a nearly uniform state, and the absorption of the colorant has a great influence on the fluorescence of the fluorescent colorant.

[0055] On the other hand, Figure 2 FIG. is a cross-sectional schematic view showing an example of a toner image formed using the resin particles of the present embodiment as a toner for electrostatic image development.

[0056] In the toner image 52 (which is a toner image formed using the resin particles of the present embodiment as a toner for electrostatic image development) formed on the recording medium 50, there are a region 54 (region RA) where the content of the above fluorescent colorant A is more than that of the above colorant B and a region 56 (region RB) where the content of the above colorant B is more than that of the above fluorescent colorant A. Particularly in a part of the region 54 (region RA), since the influence caused by the absorption of the fluorescent colorant A by the colorant B is small, the fluorescence intensity of the obtained image as a whole increases, and as a result, the vividness (chroma) as a whole also improves.

[0057] From the aspect of fluorescence intensity, the above region RA preferably includes: a region where the content of the above fluorescent colorant A is 80% by mass or more relative to the total mass of the contained colorants; more preferably includes: a region where the content of the above fluorescent colorant A is 90% by mass or more relative to the total mass of the contained colorants; particularly preferably includes: a region containing only the above fluorescent colorant A as the contained colorant.

[0058] In addition, from the aspect of fluorescence intensity, the above region RB preferably includes: a region where the content of the above colorant B is 80% by mass or more relative to the total mass of the contained colorants; more preferably includes: a region where the content of the above colorant B is 90% by mass or more relative to the total mass of the contained colorants; particularly preferably includes: a region containing only the above colorant B as the contained colorant.

[0059] From the aspect of fluorescence intensity, preferably 80% by mass or more of the total mass of the above fluorescent colorant A contained in the above resin particles is included in the above region RA, and more preferably 90% by mass or more is included in the above region RA.

[0060] In addition, from the aspect of fluorescence intensity, preferably 80% by mass or more of the total mass of the above colorant B contained in the above resin particles is included in the above region RB, and more preferably 90% by mass or more is included in the above region RB.

[0061] Furthermore, from the aspect of fluorescence intensity, it is preferable that 80% by mass or more of the total mass of the fluorescent colorant A contained in the resin particles is contained in the region RA and 80% by mass or more of the total mass of the colorant B is contained in the region RB. More preferably, 90% by mass or more of the total mass of the fluorescent colorant A contained in the resin particles is contained in the region RA and 90% by mass or more of the total mass of the colorant B is contained in the region RB.

[0062] In the resin particles, there is no particular limitation on the structure formed by the region RA and the region RB, and examples thereof include a sea-island structure, an interpenetrating network structure, and a core-shell structure.

[0063] Among them, in the resin particles, from the aspect of fluorescence intensity, it is preferable that the region RA and the region RB form a sea-island structure or an interpenetrating network structure, and more preferably a sea-island structure.

[0064] In addition, as the sea-island structure, from the aspect of fluorescence intensity, it is preferable that the region RA forms an island structure and the region RB forms a sea structure.

[0065] Furthermore, from the aspect of fluorescence intensity, the ratio (VI / VT) of the volume average particle diameter VI of the island structure in the sea-island structure to the volume average particle diameter VT of the resin particles is preferably 0.15 or more and 0.80 or less, more preferably 0.20 or more and 0.75 or less, and particularly preferably 0.30 or more and 0.65 or less.

[0066] In addition, as the resin particles, it is preferable to include at least resin particles having two or more sea structures.

[0067] The volume average particle diameter of the island structure in the sea-island structure is not particularly limited, and is preferably 1 μm or more and less than (the volume average particle diameter of the resin particles), more preferably 2 μm or more and less than (the volume average particle diameter of the resin particles), further preferably 2.5 μm or more and less than (the volume average particle diameter of the resin particles), and particularly preferably 2.5 μm or more and less than (the volume average particle diameter of the resin particles - 1 μm).

[0068] The confirmation of the sea-island structure and the like in the resin particles is carried out by the following method.

[0069] Embed resin particles in resin to prepare a specimen. Use a microtome to prepare sections from the prepared specimen. Smooth the surface (CP) / etch (IM) the prepared sections using an ion milling device RES101 (manufactured by LEICA). Observe the cross-sectional images of the resin particles in the sections that have undergone the above treatments, and confirm the sea-island structure, etc. by the color difference between region RA and region RB.

[0070] In addition, regarding the volume average particle diameter VI of the island structure in the sea-island structure of the above resin particles, perform cross-sectional observation on 50 or more resin particles using the same method as the above method for confirming the sea-island structure, etc., measure the equivalent circle diameter of the island structure in the sea-island structure, take the average value for 50 island structures with large equivalent circle diameters, and use this average value as the volume average particle diameter VI of the island structure.

[0071] In addition, in the cross-section of the resin particles, the proportion of the above region RA is preferably 10 area% or more and 90 area% or less, more preferably 20 area% or more and 80 area% or less.

[0072] Regarding the measurement method of the proportion of the above region RA, as described above, perform cross-sectional observation on 50 or more resin particles and take the average value.

[0073] - Fluorescent colorant A -

[0074] The fluorescent colorant A only needs to be a colorant that exhibits fluorescence, and preferably a colorant that exhibits fluorescence in the visible light region (wavelength 380 nm or more and 760 nm or less). In addition, the light that excites the fluorescent colorant A is not particularly limited, and preferably includes at least visible light or ultraviolet light, more preferably at least ultraviolet light.

[0075] In addition, the fluorescent colorant A can be a fluorescent pigment or a fluorescent dye, and preferably a fluorescent dye.

[0076] It should be noted that in the present embodiment, "pigment" refers to a colorant with a solubility in 100 g of water at 23°C and a solubility in 100 g of cyclohexanone at 23°C both less than 0.1 g, and "dye" refers to a colorant with a solubility in 100 g of water at 23°C or a solubility in 100 g of cyclohexanone at 23°C of 0.1 g or more.

[0077] In addition, the color of the fluorescent colorant A is not particularly limited, and can be appropriately selected according to the expectation.

[0078] Examples of the fluorescent colorant A include fluorescent pink colorant, fluorescent red colorant, fluorescent orange colorant, fluorescent yellow colorant, fluorescent green colorant, fluorescent purple colorant, etc.

[0079] Among them, it is preferably a fluorescent pink colorant, a fluorescent red colorant, a fluorescent orange colorant, a fluorescent yellow colorant or a fluorescent green colorant, more preferably a fluorescent pink colorant, a fluorescent yellow colorant or a fluorescent green colorant, and particularly preferably a fluorescent pink colorant.

[0080] In addition, the resin particles of this embodiment are preferably fluorescent resin particles, more preferably fluorescent pink resin particles, fluorescent yellow resin particles or fluorescent green resin particles, and particularly preferably fluorescent pink resin particles.

[0081] The fluorescence peak wavelength of the fluorescent colorant under the spectral reflectance can be appropriately selected according to the desired color. For example, when it is desired to exhibit a fluorescent pink color, it preferably has a fluorescence peak wavelength of 560 nm or more and 670 nm or less, and more preferably 580 nm or more and 650 nm or less.

[0082] Figure 5 An example of the spectrum in each color of the fluorescent color is shown. The vertical axis represents the fluorescence intensity and the horizontal axis represents the wavelength. It should be noted that "mμ" = "nm".

[0083] In addition, from the aspect of the graininess of the image, the value of the spectral reflectance of the fluorescent colorant at the above fluorescence peak wavelength is preferably 104% or more, more preferably 108% or more, and particularly preferably 112% or more.

[0084] As the fluorescent colorant A, known fluorescent colorants can be used. Specifically, for example, basic red 1 (rhodamine 6G), basic red 1:1, basic red 2, basic red 12, basic red 13, basic red 14, basic red 15, basic red 36, basic violet 7, basic violet 10 (rhodamine B), basic violet 11 (rhodamine 3B), basic violet 11:1 (rhodamine A), basic violet 15, basic violet 16, basic violet 27, pigment yellow 101, basic yellow 1, basic yellow 2, basic yellow 9, basic yellow 24, basic yellow 40, basic orange 15, basic orange 22, basic blue 1, basic blue 3, basic blue 7, basic blue 9, basic blue 45, basic green 1, acid yellow 3, acid yellow 7, acid yellow 73, acid yellow 87, acid yellow 184, acid yellow 245, acid yellow 250, acid red 51, acid red 52, acid red 57, acid red 77, acid red 87, acid red 89, acid red 92, acid blue 9, acid black 2, solvent yellow 43, solvent yellow 44, solvent yellow 85, solvent yellow 98, solvent yellow 116, solvent yellow 131, solvent yellow 145, solvent yellow 160:1, solvent yellow 172, solvent yellow 185, solvent yellow 195, solvent yellow 196, solvent orange 63, solvent orange 112, solvent red 49, solvent red 149, solvent red 175, solvent red 196, solvent red 197, solvent blue 5, solvent green 5, solvent green 7, direct yellow 27, direct yellow 85, direct yellow 96, direct orange 8, direct red 2, direct red 9, direct blue 22, direct blue 199, direct green 6, disperse yellow 11, disperse yellow 82, disperse yellow 139, disperse yellow 184, disperse yellow 186, disperse yellow 199, disperse yellow 202, disperse yellow 232, disperse orange 11, disperse orange 32, disperse red 58, disperse red 274, disperse red 277, disperse red 303, disperse blue 7, reactive yellow 78, vat red 41, etc. can be cited.

[0085] One or more of these fluorescent colorants can be selected according to the desired color. For example, in the case where it is desired to exhibit fluorescent pink, it is preferably at least one fluorescent colorant selected from the group consisting of basic red 1 (rhodamine 6G), basic red 1:1, basic red 2, basic red 12, basic red 13, basic red 14, basic red 15, basic red 36, basic violet 7, basic violet 10 (rhodamine B), basic violet 11 (rhodamine 3B), basic violet 11:1 (rhodamine A), basic violet 15, basic violet 16, and basic violet 27.

[0086] In addition, as the fluorescent colorant A, from the viewpoints of fluorescence intensity and hue, it is preferably a fluorescent colorant having a xanthene structure, a naphthalene structure, or a triarylmethane structure, and more preferably a fluorescent colorant having a xanthene structure.

[0087] In addition, the xanthene structure is preferably a rhodamine structure, a fluorescein structure, or an eosin structure, and more preferably a rhodamine structure.

[0088] In the resin particles, the fluorescent colorant A may be contained alone as one kind, or two or more kinds may be contained in combination.

[0089] Regarding the content of the fluorescent colorant A, from the aspects of fluorescence intensity and hue, it is preferably 0.2% by mass or more and 5% by mass or less, more preferably 0.2% by mass or more and 3% by mass or less, and particularly preferably 0.2% by mass or more and 2% by mass or less with respect to the whole resin particles.

[0090] - Colorant B other than the above fluorescent colorant A -

[0091] The colorant B only needs to be a colorant other than the above fluorescent colorant A, and known colorants can be used.

[0092] The colorant B is preferably a colorant that does not exhibit fluorescence in the visible light region.

[0093] In addition, the colorant B may be a pigment or a dye, and a pigment is preferred.

[0094] As coloring agent B, specifically, for example, C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 4, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 8, C.I. Pigment Red 9, C.I. Pigment Red 10, C.I. Pigment Red 11, C.I. Pigment Red 12, C.I. Pigment Red 14, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 17, C.I. Pigment Red 18, C.I. Pigment Red 21, C.I. Pigment Red 22, C.I. Pigment Red 23, C.I. Pigment Red 31, C.I. Pigment Red 32, C.I. Pigment Red 38, C.I. Pigment Red 41, C.I. Pigment Red 48, C.I. Pigment Red 48:1, C.I. Pigment Red 48:2, C.I. Pigment Red 48:3, C.I. Pigment Red 48:4, C.I. Pigment Red 49, C.I. Pigment Red 52, C.I. Pigment Red 53:1, C.I. Pigment Red 54, C.I. Pigment Red 57:1, C.I. Pigment Red 58, C.I. Pigment Red 60:1, C.I. Pigment Red 63, C.I. Pigment Red 64:1, C.I. Pigment Red 68, C.I. Pigment Red 81:1, C.I. Pigment Red 81:4, C.I. Pigment Red 83, C.I. Pigment Red 88, C.I. Pigment Red 89, C.I. Pigment Red 112, C.I. Pigment Red 114, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 144, C.I. Pigment Red 146, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 166, C.I. Pigment Red 170, C.I. Pigment Red 176, C.I. Pigment Red 177, C.I. Pigment Red 178, C.I. Pigment Red 179, C.I. Pigment Red 184, C.I. Pigment Red 185, C.I. Pigment Red 187, C.I. Pigment Red 202, C.I. Pigment Red 206, C.I. Pigment Red 207, C.I. Pigment Red 208, C.I. Pigment Red 209, C.I. Pigment Red 210, C.I. Pigment Red 220, C.I. Pigment Red 221, C.I. Pigment Red 238, C.I. Pigment Red 242, C.I. Pigment Red 245, C.I. Pigment Red 253, C.I. Pigment Red 254, C.I. Pigment Red 255, C.I. Pigment Red 256, C.I. Pigment Red 258, C.I. Pigment Red 264, C.I. Pigment Red 266, C.I. Pigment Red 269, C.I. Pigment Red 282, etc.; Pigment Violet 19; C.I. Solvent Red 1, C.I. Solvent Red 3, C.I. Solvent Red 8, C.I. Solvent Red 23, C.I. Solvent Red 24, C.I. Solvent Red 25, C.I. Solvent Red 27, C.I. Solvent Red 30, C.I. Solvent Red 49, C.I. Solvent Red 52, C.I. Solvent Red 58, C.I.Magenta dyes such as Solvent Red 63, C.I. Solvent Red 81, C.I. Solvent Red 82, C.I. Solvent Red 83, C.I. Solvent Red 84, C.I. Solvent Red 100, C.I. Solvent Red 109, C.I. Solvent Red 111, C.I. Solvent Red 121, C.I. Solvent Red 122, C.I. Disperse Red 9, C.I. Basic Red 1, C.I. Basic Red 2, C.I. Basic Red 9, C.I. Basic Red 12, C.I. Basic Red 13, C.I. Basic Red 14, C.I. Basic Red 15, C.I. Basic Red 17, C.I. Basic Red 18, C.I. Basic Red 22, C.I. Basic Red 23, C.I. Basic Red 24, C.I. Basic Red 27, C.I. Basic Red 29, C.I. Basic Red 32, C.I. Basic Red 34, C.I. Basic Red 35, C.I. Basic Red 36, C.I. Basic Red 37, C.I. Basic Red 38, C.I. Basic Red 39, C.I. Basic Red 40, etc.; various pigments such as Iron Oxide Red, Cadmium Red, Red Lead, Vermilion, Permanent Red 4R, Lithol Red, Pyrazolone Red, Watching Red, Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B, Carbon Black, Chrome Yellow, Hansa Yellow, Benzidine Yellow, Vat Yellow, Quinoline Yellow, Pigment Yellow, Permanent Orange GTR, Pyrazolone Orange, Sulfur Fast Orange, Brilliant Carmine 3B, Brilliant Carmine 6B, DuPont Oil Red, Lake Red C, Aniline Blue, Ultramarine Blue, Oil Soluble Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Phthalocyanine Green, Malachite Green Oxalate, etc. In addition, it is also suitable to be a solid solution pigment (a pigment in which two or more pigments are solidified to change their crystal structure). Specifically, different combinations of quinacridone substituents (unsubstituted quinacridone PV19 and PR122, PV19 and PR202, etc.) can be cited as an example.

[0095] The colorant B is appropriately selected according to the desired color. For example, in the case of wanting to show a fluorescent pink color, a magenta pigment can be cited as an example. Among them, a solid solution pigment is suitable. As for the fluorescent color, if it produces a bright color or a dark color even for the same hue, the performance is good, and by using a solid solution pigment, the performance tends to be improved.

[0096] The colorant B can be used alone or in combination of two or more.

[0097] The colorant B can use a colorant that has been surface-treated as needed, or can be used in combination with a dispersant. In addition, two or more colorants can also be used in combination.

[0098] As the content of coloring agent B, from the viewpoints of fluorescence intensity and hue, it is preferably 0.1% by mass or more and 2% by mass or less, more preferably 0.1% by mass or more and 1.5% by mass or less, and particularly preferably 0.1% by mass or more and 1% by mass or less with respect to the whole resin particles.

[0099] From the viewpoints of fluorescence intensity and hue, the value of the ratio (WB / WA) of the content WA of fluorescent coloring agent A to the content WB of coloring agent B in the resin particles is preferably 1.25 or less, more preferably 1.0 or less, and particularly preferably 0.5 or less.

[0100] -Binder resin-

[0101] As the binder resin, for example, vinyl resins formed from homopolymers of the following monomers or copolymers formed by combining two or more of these monomers can be mentioned. The monomers are: styrenes (such as styrene, p-chlorostyrene, α-methylstyrene, etc.), (meth)acrylates (such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc.), ethylenically unsaturated nitriles (such as acrylonitrile, methacrylonitrile, etc.), vinyl ethers (such as vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (such as vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), olefins (such as ethylene, propylene, butadiene, etc.), etc.

[0102] As the binder resin, non-vinyl resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, modified rosin, etc., mixtures of these resins with the above vinyl resins, or graft polymers obtained by polymerizing vinyl monomers in the coexistence of these resins can also be mentioned.

[0103] Among them, styrene-acrylic copolymers or polyester resins are suitably used, and polyester resins are more suitably used.

[0104] These binder resins can be used alone or in combination of two or more.

[0105] In addition, as the binder resin, from the viewpoints of dispersibility of the coloring agent, fluorescence intensity, and hue, a polyurethane resin is preferably contained.

[0106] As the polyurethane resin, it can be a polyester polyurethane resin, a polyether polyurethane resin, etc. Among them, a polyester polyurethane resin is preferred. As the polyester polyurethane resin, for example, a resin obtained by reacting a polyisocyanate compound (preferably a diisocyanate compound) with a polyester resin (preferably a polyester diol) having at least one group selected from the group consisting of a hydroxyl group and a carboxyl group is preferably exemplified.

[0107] In addition, as the adhesive resin, from the viewpoints of the dispersibility of the colorant, the fluorescence intensity, and the hue, it is preferably composed of a polyurethane resin and a styrene-acrylic copolymer or a polyester resin, and more preferably composed of a polyurethane resin and a polyester resin. Further, in the case of containing a styrene-acrylic copolymer, an acrylic-polyurethane resin is preferred from the viewpoint of compatibility.

[0108] For example, a mode in which a polyurethane resin is contained as the adhesive resin in the island structure and a styrene-acrylic copolymer or a polyester resin is contained as the adhesive resin in the sea structure in the above-mentioned sea-island structure is preferably exemplified.

[0109] As the adhesive resin, an amorphous (also referred to as "non-crystalline") resin and a crystalline resin can be exemplified.

[0110] From the viewpoint of suppressing the density unevenness in the obtained image, the adhesive resin preferably contains a crystalline resin, and more preferably contains an amorphous resin and a crystalline resin.

[0111] Relative to the total mass of the adhesive resin, the content of the crystalline resin is preferably 2% by mass or more and 40% by mass or less, and more preferably 2% by mass or more and 20% by mass or less.

[0112] It should be noted that the "crystallinity" of the resin means that there is no stepped heat absorption change in differential scanning calorimetry (DSC) and there is a clear endothermic peak. Specifically, it means that the half-width at half-maximum of the endothermic peak when measured at a heating rate of 10 (°C / min) is within 10 °C.

[0113] On the other hand, the "amorphousness" of the resin means that the half-width at half-maximum is greater than 10 °C, a stepped heat absorption change is shown, or no clear endothermic peak is found.

[0114] <<Polyester resin>>

[0115] As the polyester resin, for example, known polyester resins can be exemplified.

[0116] · Amorphous polyester resin

[0117] As the amorphous polyester resin, for example, a condensate of a polycarboxylic acid and a polyol can be exemplified. It should be noted that as the amorphous polyester resin, commercially available products can be used, or synthetic products can be used.

[0118] As the polycarboxylic acid, for example, aliphatic dicarboxylic acids (such as oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, pentenedioic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.), alicyclic dicarboxylic acids (such as cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acids (such as terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), their acid anhydrides or their lower (e.g., having 1 to 5 carbon atoms) alkyl esters can be cited. Among these, as the polycarboxylic acid, aromatic dicarboxylic acids are preferably used, for example.

[0119] In the polycarboxylic acid, a dicarboxylic acid can be used in combination with a polycarboxylic acid having 3 or more carboxyl groups that adopts a crosslinked structure or a branched structure. As the polycarboxylic acid having 3 or more carboxyl groups, for example, trimellitic acid, pyromellitic acid, their acid anhydrides or their lower (e.g., having 1 to 5 carbon atoms) alkyl esters, etc. can be cited.

[0120] The polycarboxylic acid can be used alone or in combination of two or more.

[0121] As the polyol, for example, aliphatic diols (such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butylene glycol, hexanediol, neopentyl glycol, etc.), alicyclic diols (such as cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc.), aromatic diols (such as ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, etc.) can be cited. Among these, as the polyol, aromatic diols and alicyclic diols are preferably used, for example, and aromatic diols are more preferably used.

[0122] As the polyol, a diol can be used in combination with a polyol having 3 or more hydroxyl groups that adopts a crosslinked structure or a branched structure. As the polyol having 3 or more hydroxyl groups, for example, glycerin, trimethylolpropane, pentaerythritol can be cited.

[0123] The polyol can be used alone or in combination of two or more.

[0124] The glass transition temperature (Tg) of the amorphous polyester resin is preferably 50°C or higher and 80°C or lower, more preferably 50°C or higher and 65°C or lower.

[0125] It should be noted that the glass transition temperature is obtained from the DSC curve obtained by differential scanning calorimetry (DSC). More specifically, it is obtained according to the "extrapolated glass transition start temperature" described in the glass transition temperature measurement method of JIS K7121:1987 "Plastics - Method for Measuring Transition Temperature".

[0126] The weight average molecular weight (Mw) of the amorphous polyester resin is preferably 5,000 or higher and 1,000,000 or lower, more preferably 7,000 or higher and 500,000 or lower.

[0127] The number-average molecular weight (Mn) of the amorphous polyester resin is preferably 2,000 or more and 100,000 or less.

[0128] The molecular weight distribution Mw / Mn of the amorphous polyester resin is preferably 1.5 or more and 100 or less, more preferably 2 or more and 60 or less.

[0129] It should be noted that the weight-average molecular weight and the number-average molecular weight are measured by gel permeation chromatography (GPC). In the molecular weight measurement using GPC, GPC·HLC-8120GPC manufactured by Tosoh Corporation is used as the measurement device, column·TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation is used, and the measurement is carried out using THF solvent. The weight-average molecular weight and the number-average molecular weight are calculated based on the measurement results using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

[0130] The amorphous polyester resin is obtained by a known production method. Specifically, for example, it is obtained by the following method: the polymerization temperature is 180°C or more and 230°C or less, the reaction system is depressurized as needed, and the reaction is carried out while removing the water or alcohol generated during condensation.

[0131] It should be noted that when the raw material monomers are insoluble or incompatible at the reaction temperature, a high-boiling solvent can be added as a dissolution aid to dissolve them. In this case, the polycondensation reaction is carried out while distilling off the dissolution aid. In the case where there are monomers with poor compatibility, the monomers with poor compatibility can be pre-condensed with the acid or alcohol to be polycondensed with this monomer, and then polycondensed together with the main component.

[0132] · Crystalline polyester resin

[0133] Examples of the crystalline polyester resin include polycondensates of polycarboxylic acids and polyols. It should be noted that as the crystalline polyester resin, commercially available products or synthetic products can be used.

[0134] Here, in order to make the crystalline polyester resin easily form a crystal structure, compared with the polycondensate obtained using a polymerizable monomer having an aromatic group, the crystalline polyester preferably uses a polycondensate obtained using a polymerizable monomer having a linear aliphatic group.

[0135] As the polycarboxylic acid, for example, aliphatic dicarboxylic acids (such as oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc.), aromatic dicarboxylic acids (such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid and other dibasic acids, etc.), their acid anhydrides or their lower (for example, having 1 to 5 carbon atoms) alkyl esters can be cited.

[0136] Among the polycarboxylic acids, a dicarboxylic acid can be used in combination with a polycarboxylic acid having 3 or more carboxyl groups adopting a crosslinked structure or a branched structure. As the tricarboxylic acid, for example, aromatic carboxylic acids (such as 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc.), their acid anhydrides or their lower (for example, having 1 to 5 carbon atoms) alkyl esters can be cited.

[0137] As the polycarboxylic acid, these dicarboxylic acids can be used in combination with a dicarboxylic acid having a sulfonic acid group and a dicarboxylic acid having an ethylenic double bond.

[0138] The polycarboxylic acid can be used alone or in combination of two or more.

[0139] As the polyol, for example, aliphatic diols (such as a straight-chain aliphatic diol having 7 or more and 20 or less carbon atoms in the main chain part) can be cited. As the aliphatic diol, for example, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosanediol, etc. can be cited. Among these, as the aliphatic diol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferred.

[0140] Among the polyols, a diol can be used in combination with an alcohol having 3 or more hydroxyl groups adopting a crosslinked structure or a branched structure. As the alcohol having 3 or more hydroxyl groups, for example, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, etc. can be cited.

[0141] The polyol can be used alone or in combination of two or more.

[0142] Here, among the polyols, the content of the aliphatic diol is preferably 80 mol% or more, more preferably 90 mol% or more.

[0143] The melting temperature of the crystalline polyester resin is preferably 50°C or higher and 100°C or lower, more preferably 55°C or higher and 90°C or lower, and further preferably 60°C or higher and 85°C or lower.

[0144] It should be noted that the melting temperature is determined as the "melting peak temperature" described in the melting temperature measurement method of JIS K7121:1987 "Method for Measuring the Transition Temperature of Plastics" based on the DSC curve obtained by differential scanning calorimetry (DSC).

[0145] The weight-average molecular weight (Mw) of the crystalline polyester resin is preferably 6,000 or more and 35,000 or less.

[0146] The crystalline polyester resin is obtained, for example, by a known production method in the same manner as the amorphous polyester resin.

[0147] From the aspect of the abrasion resistance of the image, the weight-average molecular weight (Mw) of the adhesive resin is preferably 5,000 or more and 1,000,000 or less, more preferably 7,000 or more and 500,000 or less, and particularly preferably 25,000 or more and 60,000 or less. The number-average molecular weight (Mn) of the adhesive resin is preferably 2,000 or more and 100,000 or less. The molecular weight distribution Mw / Mn of the adhesive resin is preferably 1.5 or more and 100 or less, more preferably 2 or more and 60 or less.

[0148] The weight-average molecular weight and the number-average molecular weight of the adhesive resin are measured by gel permeation chromatography (GPC). In the molecular weight measurement using GPC, GPC·HLC-8120GPC manufactured by Tosoh Corporation is used as the measurement device, column·TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation is used, and the measurement is carried out using a tetrahydrofuran (THF) solvent. The weight-average molecular weight and the number-average molecular weight are calculated based on the measurement results using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

[0149] The content of the adhesive resin is preferably 40% by mass or more and 95% by mass or less, more preferably 50% by mass or more and 90% by mass or less, and further preferably 60% by mass or more and 85% by mass or less with respect to the whole resin particles.

[0150] -Release agent-

[0151] Examples of the release agent include: hydrocarbon waxes; natural waxes such as carnauba wax, rice bran wax, and candelilla wax; synthetic or mineral·petroleum-based waxes such as montan wax; ester-based waxes such as fatty acid esters and montanic acid esters; and the like. The release agent is not limited thereto.

[0152] The melting temperature of the release agent is preferably 50°C or more and 110°C or less, more preferably 60°C or more and 100°C or less.

[0153] The melting temperature is determined as the "melting peak temperature" described in the melting temperature measurement method of JIS K7121:1987 "Plastics - Method of Measuring Transition Temperature" based on the DSC curve obtained by differential scanning calorimetry (DSC).

[0154] The content of the release agent is preferably 1% by mass or more and 20% by mass or less, more preferably 5% by mass or more and 15% by mass or less, relative to the whole resin particles.

[0155] - Other additives -

[0156] As other additives, known additives such as magnetic materials, charge control agents, and inorganic powders can be cited. These additives can be included in the resin particles as internal additives.

[0157] - Characteristics of resin particles, etc. -

[0158] The resin particles can be resin particles with a single-layer structure or so-called core / shell structure resin particles (core / shell type particles) composed of a core part (nuclear particles) and a coating layer (shell layer) covering the core part. The core / shell structure resin particles are composed of, for example, a core part containing a binder resin and, if necessary, a colorant and a release agent, etc., and a coating layer containing a binder resin.

[0159] Among them, as the resin particles, resin particles having a core / shell structure are preferred. When a dye is used as the fluorescent colorant A or the colorant B, since the dye is easily fused with water, when the dye exists on the surface of the resin particles, it may have some influence on the electrical characteristics; while when a shell structure is formed using a resin not containing a dye, since the dye is enclosed inside, such an influence is not easily brought about, which is suitable.

[0160] As the volume average particle diameter (D 50v ) of the resin particles, it is preferably 2 μm or more and 10 μm or less, more preferably 4 μm or more and 8 μm or less, and particularly preferably 5 μm or more and 6 μm or less.

[0161] Regarding the volume average particle diameter of the resin particles, Coulter Multisizer II (manufactured by Beckman Coulter) is used, and ISOTON-II (manufactured by Beckman Coulter) is used as the electrolyte for measurement.

[0162] At the time of measurement, 0.5 mg or more and 50 mg or less of the measurement sample is added to 2 ml of a 5% by mass aqueous solution of a surfactant (preferably sodium alkylbenzenesulfonate) as a dispersant. It is added to 100 ml or more and 150 ml or less of the electrolyte.

[0163] The electrolyte suspension with the sample was dispersed for 1 minute using an ultrasonic disperser, and Coulter Multisizer II was used to measure the particle size of particles in the range of 2 μm or more and 60 μm or less using a pore with a pore diameter of 100 μm. The number of sampled particles was 50,000.

[0164] For the measured particle size, a volume-based cumulative distribution is plotted starting from the small-diameter side, and the particle size at the cumulative 50% point is defined as the volume average particle size D 50v 。

[0165] There is no particular limitation on the average roundness of the resin particles in this embodiment. From the aspect of maintaining good cleanliness of the image, it is preferably 0.91 or more and 0.98 or less, more preferably 0.94 or more and 0.98 or less, and further preferably 0.95 or more and 0.97 or less.

[0166] The roundness of the resin particles in this embodiment refers to (the circumference of a circle having the same area as the particle projection image) ÷ (the circumference of the particle projection image). The average roundness of the resin particles refers to the roundness at the cumulative 50% point starting from the small-roundness side in the roundness distribution. The average roundness of the resin particles is obtained by analyzing at least 3,000 resin particles using a flow particle image analyzer.

[0167] Regarding the average roundness of the resin particles, for example, in the case of manufacturing resin particles by the agglomeration and coalescence method, it can be controlled by adjusting the stirring speed, temperature, or holding time of the dispersion liquid in the fusion / coalescence step.

[0168] (External additive)

[0169] When the resin particles are used as a toner for electrostatic image development described later, the resin particles may contain an external additive as needed.

[0170] In addition, the resin particles may be resin particles without an external additive, or particles obtained by externally adding an external additive to the resin particles.

[0171] As the external additive, for example, inorganic particles can be cited. As the above inorganic particles, SiO 2 , TiO 2 , Al 2 O 3 , CuO, ZnO, SnO 2 , CeO 2 , Fe 2 O 3 , MgO, BaO, CaO, K 2 O, Na 2 O, ZrO 2 , CaO·SiO2 , K 2 O·(TiO 2 ) n , Al 2 O 3 ·2SiO 2 , CaCO 3 , MgCO 3 , BaSO 4 , MgSO 4 , etc.

[0172] The surface of the inorganic particles as external additives can also be subjected to a hydrophobization treatment. The hydrophobization treatment is carried out, for example, by impregnating the inorganic particles in a hydrophobization treatment agent, etc. The hydrophobization treatment agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents, etc. These treatment agents can be used alone or in combination of two or more.

[0173] As the amount of the hydrophobization treatment agent, for example, it is preferably 1 part by mass or more and 10 parts by mass or less relative to 100 parts by mass of the inorganic particles.

[0174] As external additives, resin particles (resin particles such as polystyrene, polymethyl methacrylate (PMMA), melamine resin, etc.), cleaning agents (for example, metal salts of higher fatty acids represented by zinc stearate, particles of fluorine-based high molecular weight substances), etc. can also be cited.

[0175] As the addition amount of the external additives, for example, it is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.01% by mass or more and 6% by mass or less relative to the resin particles.

[0176] <Use of resin particles>

[0177] The resin particles of the present embodiment are suitable for use as resin particles for image formation, and more suitable for use as toner for electrostatic image development.

[0178] In addition, the resin particles of the present embodiment are also suitable for use as powder coatings. The powder coatings can also be used to manufacture coated products. After the powder coatings are coated on the coated surface, heating (baking) is carried out to cure the powder to form a coating film, and the coated products are manufactured. At this time, coating and heating (baking) can be carried out uniformly.

[0179] Coating of the powder can be carried out by known coating methods such as spray coating, electrostatic powder coating, tribocharging powder coating, dip coating, etc. The thickness of the coating film of the powder is, for example, preferably 30 μm or more and 50 μm or less.

[0180] The heating temperature (calcination temperature) is preferably, for example, 90°C or higher and 250°C or lower, more preferably 100°C or higher and 220°C or lower, and still more preferably 120°C or higher and 200°C or lower. It should be noted that the heating time (calcination time) is adjusted according to the heating temperature (calcination temperature).

[0181] The object articles to be coated with the powder are not particularly limited, and various metal parts, ceramic parts, resin parts, etc. can be cited. These object articles can be unformed articles before being formed into various articles such as plate-shaped articles and linear articles, or formed articles for electronic components, road vehicles, building interior and exterior decoration materials, etc. In addition, the object articles can be articles that have been subjected to surface treatments such as primer coating treatment, plating treatment, and electrodeposition coating on the coated surface in advance.

[0182] In addition, in fields other than coating, the resin particles of the present embodiment can also be suitably used as resin particles for electrophotographic displays.

[0183] Electrophotographic displays that disperse charged resin particles in a medium (mostly air) and display images by moving the resin particles under the action of an electric field are well known. The resin particles of the present embodiment can also be used in such electrophotographic displays without problems. For example, resin particles are loaded into a cell (cell) sandwiched between two transparent electrodes, and a voltage is applied to move the resin particles, thereby displaying an image.

[0184] [Method for manufacturing resin particles]

[0185] Next, the method for manufacturing the resin particles of the present embodiment will be described.

[0186] For the resin particles of the present embodiment, external additives can be externally added to the resin particles after manufacturing the resin particles.

[0187] The resin particles can be manufactured by any one of a dry method (such as a kneading and pulverizing method, etc.) and a wet method (such as an agglomeration and combination method, a suspension polymerization method, a dissolution and suspension method, etc.). These manufacturing methods are not particularly limited, and known manufacturing methods can be adopted. Among these, it is preferable to obtain the resin particles by the agglomeration and combination method.

[0188] As the agglomeration and combination method, for example, the methods described in Japanese Patent Application Laid-Open No. 2010-97101 or Japanese Patent Application Laid-Open No. 2006-154641 can be cited.

[0189] As the kneading and pulverizing method, for example, the method described in Japanese Patent Application Laid-Open No. 2000-267338 can be cited.

[0190] As the dissolution and suspension method, the method described in Japanese Patent Application Laid-Open No. 2000-258950 can be cited.

[0191] In addition, specifically, for example, in the case of manufacturing resin particles by the agglomeration and coalescence method, the resin particles are manufactured through the following steps: a step of preparing a resin particle dispersion liquid in which resin particles as a binder resin are dispersed (resin particle dispersion liquid preparation step); a step of causing the resin particles (and other particles if necessary) to agglomerate in the resin particle dispersion liquid (or the dispersion liquid after mixing other particle dispersion liquids if necessary) to form agglomerated particles (agglomerated particle formation step); and a step of heating the agglomerated particle dispersion liquid in which the agglomerated particles are dispersed to cause the agglomerated particles to fuse / coalesce (fuse and unite) to form resin particles (fusion / coalescence step).

[0192] Details of each step will be described below.

[0193] In the following description, a method for obtaining resin particles containing a colorant and a release agent will be described, but the colorant and the release agent are components used as needed. Of course, other additives other than the colorant and the release agent can also be used.

[0194] In addition, in the following description, as the colorant, at least one colorant selected from the group consisting of the above-mentioned fluorescent colorant A and the above-mentioned colorant B can be cited. In addition, as the colorant particle dispersion liquid, a fluorescent colorant A particle dispersion liquid and a colorant B particle dispersion liquid can also be prepared. Furthermore, the above-mentioned fluorescent colorant A particle dispersion liquid is preferably prepared in the form of a resin particle dispersion liquid containing the fluorescent colorant A, and more preferably in the form of a urethane resin particle dispersion liquid containing the fluorescent colorant A. In addition, in the above-mentioned resin particle dispersion liquid containing the fluorescent colorant A, the above-mentioned colorant B can be used instead of the above-mentioned fluorescent colorant A to form a resin particle dispersion liquid containing the colorant B.

[0195] - Resin particle dispersion liquid preparation step -

[0196] Prepare a resin particle dispersion liquid in which resin particles as a binder resin are dispersed, and at the same time prepare, for example, a colorant particle dispersion liquid in which colorant particles are dispersed and a release agent particle dispersion liquid in which release agent particles are dispersed.

[0197] The resin particle dispersion liquid is prepared, for example, by dispersing resin particles in a dispersion medium using a surfactant.

[0198] As the dispersion medium used in the resin particle dispersion liquid, for example, an aqueous medium can be cited.

[0199] As the aqueous medium, for example, water such as distilled water and ion-exchanged water, alcohols, etc. can be cited. These media can be used alone or in combination of two or more.

[0200] As surfactants, examples include: anionic surfactants such as sulfate ester salts, sulfonate salts, phosphate esters, and soaps; cationic surfactants such as amine salts and quaternary ammonium salts; nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyols; and so on. Among these, anionic surfactants and cationic surfactants are particularly preferred. Nonionic surfactants can also be used in combination with anionic surfactants or cationic surfactants.

[0201] Among them, it is preferable to use nonionic surfactants, and it is preferable to use nonionic surfactants in combination with anionic surfactants or cationic surfactants.

[0202] Surfactants can be used alone or in combination of two or more.

[0203] In the resin particle dispersion, as a method for dispersing resin particles in a dispersion medium, common dispersion methods such as using a rotary shear homogenizer or a ball mill, sand mill, bead mill, etc. having a medium can be cited. In addition, depending on the type of resin particles, the resin particles can also be dispersed in the dispersion medium by the phase inversion emulsification method. The phase inversion emulsification method is the following method: dissolving the resin to be dispersed in a hydrophobic organic solvent that can dissolve the resin, adding a base to the organic continuous phase (O phase) for neutralization, and then introducing an aqueous medium (W phase), thereby inverting from W / O to O / W and dispersing the resin in the form of particles in the aqueous medium.

[0204] As the volume average particle diameter of the resin particles dispersed in the resin particle dispersion, for example, it is preferably 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, and further preferably 0.1 μm or more and 0.6 μm or less.

[0205] Regarding the volume average particle diameter of the resin particles, a particle size distribution obtained by measurement using a laser diffraction particle size distribution measuring device (for example, LA-700 manufactured by Horiba, Ltd.) is used. For the divided particle size ranges (sections), a cumulative volume distribution is plotted starting from the small particle size side, and the particle diameter at the cumulative 50% point relative to all particles is measured and used as the volume average particle diameter D50v. The volume average particle diameter of the particles in other dispersions is also measured in the same manner.

[0206] The content of the adhesive resin particles contained in the resin particle dispersion is preferably 5% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 40% by mass or less.

[0207] Similarly to the resin particle dispersion liquid, for example, a colorant particle dispersion liquid and a release agent particle dispersion liquid are also prepared. That is, in terms of the volume average particle diameter, dispersion medium, dispersion method, and particle content of the particles in the resin particle dispersion liquid, the same applies to the colorant particles dispersed in the colorant particle dispersion liquid and the release agent particles dispersed in the release agent particle dispersion liquid.

[0208] -Agglomerate particle formation step-

[0209] Next, the resin particle dispersion liquid, the colorant particle dispersion liquid, and the release agent particle dispersion liquid are mixed.

[0210] After that, in the mixed dispersion liquid, the resin particles, the colorant particles, and the release agent particles are hetero-aggregated to form agglomerate particles having a diameter close to the diameter of the target resin particles and containing the resin particles, the colorant particles, and the release agent particles.

[0211] Specifically, for example, a flocculant is added to the mixed dispersion liquid, and the pH of the mixed dispersion liquid is adjusted to acidic (for example, pH 2 or more and 5 or less). A dispersion stabilizer is added as needed, and then it is heated to a temperature close to the glass transition temperature of the resin particles (specifically, for example, the glass transition temperature of the resin particles - 30°C to the glass transition temperature - 10°C) to cause the particles dispersed in the mixed dispersion liquid to aggregate and form agglomerate particles.

[0212] In the agglomerate particle formation step, for example, a flocculant can be added at room temperature (for example, 25°C) while stirring the mixed dispersion liquid with a rotary shear homogenizer, the pH of the mixed dispersion liquid is adjusted to acidic (for example, pH 2 or more and 5 or less), and after adding a dispersion stabilizer as needed, heating is carried out.

[0213] As the flocculant, for example, a surfactant having a polarity opposite to that of the surfactant contained in the mixed dispersion liquid, an inorganic metal salt, and a metal complex having a valence of 2 or more can be cited. When a metal complex is used as the flocculant, the amount of the surfactant used is reduced and the charging characteristics are improved.

[0214] An additive that forms a complex or a similar bond with the metal ion of the flocculant can be used together with the flocculant as needed. As this additive, a chelating agent is preferably used.

[0215] As the inorganic metal salt, for example, metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate; inorganic metal salt polymers such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide; and so on can be cited.

[0216] As the chelating agent, a water-soluble chelating agent can be used. As the chelating agent, for example, hydroxycarboxylic acids such as tartaric acid, citric acid, gluconic acid; aminocarboxylic acids such as iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA); and the like can be cited.

[0217] The addition amount of the flocculant is preferably 0.01 part by mass or more and 5.0 parts by mass or less, more preferably 0.1 part by mass or more and less than 3.0 parts by mass with respect to 100 parts by mass of the resin particles.

[0218] -Fusion / merging step-

[0219] Next, the flocculated particle dispersion liquid in which the flocculated particles are dispersed is heated to, for example, a temperature above the glass transition temperature of the resin particles (for example, a temperature 30°C to 50°C higher than the glass transition temperature of the resin particles) and to a temperature above the melting temperature of the release agent, so that the flocculated particles are fused / merged to form resin particles.

[0220] In the fusion / merging step, above the glass transition temperature of the resin particles and above the melting temperature of the release agent, the resin and the release agent are in a fused state. Then, cooling is performed to obtain resin particles.

[0221] As a method for adjusting the aspect ratio of the release agent in the resin particles, by maintaining a certain time at a temperature around the freezing point of the release agent during cooling to allow crystal growth or using two or more release agents having different melting temperatures, crystal growth during cooling can be promoted, and the aspect ratio can be adjusted.

[0222] Through the above steps, resin particles are obtained.

[0223] After obtaining the flocculated particle dispersion liquid in which the flocculated particles are dispersed, resin particles can be manufactured through the following steps: a step of further mixing the above-mentioned flocculated particle dispersion liquid with a resin particle dispersion liquid in which resin particles are dispersed and performing flocculation in such a manner that the resin particles further adhere to the surface of the flocculated particles to form second flocculated particles; and a step of heating the second flocculated particle dispersion liquid in which the second flocculated particles are dispersed to fuse / merge the second flocculated particles to form resin particles having a core / shell structure.

[0224] After the fusion / merging step is completed, a known cleaning step, solid-liquid separation step, and drying step are performed on the resin particles formed in the solution to obtain resin particles in a dry state. Regarding the cleaning step, from the aspect of chargeability, replacement cleaning using ion-exchanged water can be sufficiently performed. Regarding the solid-liquid separation step, from the aspect of productivity, suction filtration, pressure filtration, etc. can be performed. Regarding the drying step, from the aspect of productivity, freeze drying, fluidized bed drying, vibration fluidized bed drying, etc. can be performed.

[0225] Thereafter, for example, an external additive is added to the obtained resin particles in a dry state and mixed, thereby producing the resin particles of the present embodiment. The mixing can be carried out, for example, using a V-type blender, a Henschel mixer, a Loedige mixer, etc. Furthermore, coarse particles of the resin particles can be removed using a vibrating sieve, an air classifier, etc. as needed.

[0226] <Electrostatic image developer>

[0227] When the resin particles of the present embodiment are used as an electrostatic image developer, it can be a one-component developer containing only the resin particles of the present embodiment, or a two-component developer formed by mixing the resin particles with a carrier.

[0228] There is no particular limitation on the carrier, and known carriers can be cited. As the carrier, for example, a coated carrier in which a resin is coated on the surface of a core material formed of magnetic powder; a magnetic powder-dispersed carrier in which magnetic powder is dispersed and mixed in a base resin; a resin-impregnated carrier in which resin penetrates into porous magnetic powder; and the like. The magnetic powder-dispersed carrier and the resin-impregnated carrier can also be carriers in which the constituent particles of the carrier are used as the core material and a resin is coated on the surface thereof.

[0229] As the magnetic powder, for example, magnetic metals such as iron, nickel, and cobalt; magnetic oxides such as ferrite and magnetite; and the like can be cited.

[0230] As the resin for coating and the base resin, for example, polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylate copolymer, a pure silicone resin or a modified product thereof formed by including a silicone-oxygen bond, a fluororesin, a polyester, a polycarbonate, a phenol resin, an epoxy resin, etc. Additives such as conductive particles can be included in the resin for coating and the base resin. As the conductive particles, particles of metals such as gold, silver, and copper, carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, potassium titanate, etc. can be cited.

[0231] Among them, from the aspect of suppressing density unevenness in the obtained image, a carrier having its surface coated with a resin containing a silicone resin is preferred, and a carrier having its surface coated with a silicone resin is more preferred.

[0232] When coating the surface of a resin-coated core material, methods such as coating with a coating solution formed by dissolving a coating resin and various additives (used as needed) in an appropriate solvent can be cited. The solvent is not particularly limited and can be selected considering the type of resin used, coating suitability, etc. As specific resin coating methods, there are: an immersion method in which the core material is immersed in the coating solution; a spraying method in which the coating solution is sprayed onto the surface of the core material; a fluidized bed method in which the coating solution is sprayed in a state where the core material is suspended by flowing air; a kneading coater method in which the core material of the carrier and the coating solution are mixed in a kneading coater and then the solvent is removed; and so on.

[0233] The mixing ratio (mass ratio) of the resin particles (toner for electrostatic image development) to the carrier in the two-component developer is preferably resin particles (toner for electrostatic image development): carrier = 1:100 to 30:100, and more preferably 3:100 to 20:100.

[0234] <Image forming apparatus, image forming method>

[0235] The image forming apparatus / image forming method in the case where the resin particles of the present embodiment are used as the toner for electrostatic image development will be described.

[0236] The image forming apparatus includes: an image carrier; a charging mechanism for charging the surface of the image carrier; an electrostatic image forming mechanism for forming an electrostatic image on the charged surface of the image carrier; a developing mechanism for storing a toner for electrostatic image development and developing the electrostatic image formed on the surface of the image carrier into a toner image; a transfer mechanism for transferring the toner image formed on the surface of the image carrier to the surface of a recording medium; and a fixing mechanism for fixing the toner image transferred to the surface of the recording medium. And, as the toner for electrostatic image development, the toner for electrostatic image development of the present embodiment is applied.

[0237] An image forming method having the following steps is implemented in the image forming apparatus: a charging step of charging the surface of the image carrier; an electrostatic image forming step of forming an electrostatic image on the charged surface of the image carrier; a developing step of developing the electrostatic image formed on the surface of the image carrier into a toner image using a toner for electrostatic image development containing the resin particles of the present embodiment; a transfer step of transferring the toner image formed on the surface of the image carrier to the surface of a recording medium; and a fixing step of fixing the toner image transferred to the surface of the recording medium.

[0238] As the image forming apparatus, the following well-known image forming apparatuses can be applied: an apparatus of a direct transfer method that directly transfers a toner image formed on the surface of an image carrier to a recording medium; an apparatus of an intermediate transfer method that transfers a toner image formed on the surface of an image carrier to the surface of an intermediate transfer body once and then transfers the toner image transferred to the surface of the intermediate transfer body to the surface of a recording medium twice; an apparatus having a cleaning mechanism that cleans the surface of the image carrier after transfer of the toner image and before charging; an apparatus having a charge removing mechanism that removes charge by irradiating the surface of the image carrier with charge removing light after transfer of the toner image and before charging; and so on.

[0239] In the case where the image forming apparatus is an apparatus of an intermediate transfer method, the transfer mechanism, for example, has a configuration having the following components: an intermediate transfer body to which a toner image is transferred to the surface; a primary transfer mechanism that transfers a toner image formed on the surface of an image carrier to the surface of the intermediate transfer body once; and a secondary transfer mechanism that transfers the toner image transferred to the surface of the intermediate transfer body to the surface of a recording medium twice.

[0240] In the image forming apparatus, for example, a portion including a developing mechanism may be a cartridge structure (processing cartridge) that can be loaded and unloaded in the image forming apparatus. As the processing cartridge, for example, a processing cartridge suitable for use is such a processing cartridge that has a developing mechanism storing an electrostatic image developer containing the resin particles of the present embodiment.

[0241] Hereinafter, an example of the image forming apparatus will be described, but it is not limited thereto. In the following description, main parts shown in the drawings will be described. Other descriptions are omitted.

[0242] Figure 3 FIG. is a schematic configuration diagram showing the image forming apparatus used in the present embodiment.

[0243] Figure 3 The shown image forming apparatus includes electrophotographic first to fourth image forming units 10Y, 10M, 10C, and 10K (image forming mechanisms) that output color images of yellow (Y), magenta (M), cyan (C), and black (K) based on color separation image data. These image forming units (hereinafter also referred to as "units") 10Y, 10M, 10C, and 10K are arranged side by side at a preset distance from each other in the horizontal direction. These units 10Y, 10M, 10C, and 10K may be processing cartridges that can be loaded and unloaded with respect to the image forming apparatus.

[0244] Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt (an example of an intermediate transfer member) 20 is provided to extend through each unit. The intermediate transfer belt 20 is wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20, and is caused to run in the direction from the first unit 10Y toward the fourth unit 10K. The support roller 24 applies a force in a direction separating from the driving roller 22 by a spring (not shown) or the like, and applies tension to the intermediate transfer belt 20 wound around the two rollers. An intermediate transfer belt cleaning device 30 opposed to the driving roller 22 is provided on the image holding surface side of the intermediate transfer belt 20.

[0245] To the developing devices (an example of a developing mechanism) 4Y, 4M, 4C, and 4K of each of the units 10Y, 10M, 10C, and 10K, yellow, magenta, cyan, and black toners stored in the toner cartridges 8Y, 8M, 8C, and 8K are respectively supplied.

[0246] The first to fourth units 10Y, 10M, 10C, and 10K have the same configuration and operation. Therefore, here, the first unit 10Y that forms a yellow image and is disposed on the upstream side in the running direction of the intermediate transfer belt will be described as a representative.

[0247] The first unit 10Y has a photoreceptor 1Y that functions as an image holding member. Around the photoreceptor 1Y, a charging roller (an example of a charging mechanism) 2Y that charges the surface of the photoreceptor 1Y to a preset potential, an exposure device (an example of an electrostatic image forming mechanism) 3 that exposes the charged surface with a laser beam 3Y based on a color separation image signal to form an electrostatic image, a developing device (an example of a developing mechanism) 4Y that supplies the charged toner to the electrostatic image to develop the electrostatic image, a primary transfer roller (an example of a primary transfer mechanism) 5Y that transfers the developed toner image onto the intermediate transfer belt 20, and a photoreceptor cleaning device (an example of an image holding member cleaning mechanism) 6Y that removes the toner remaining on the surface of the photoreceptor 1Y after primary transfer are sequentially arranged.

[0248] The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20 and is provided at a position opposed to the photoreceptor 1Y. The primary transfer rollers 5Y, 5M, 5C, and 5K of each unit are respectively connected to a bias power source (not shown) that applies a primary transfer bias. Each bias power source changes the value of the transfer bias applied to each primary transfer roller by the control of a control unit (not shown).

[0249] Next, the operation of forming a yellow image in the first unit 10Y will be described.

[0250] First, before the operation, the surface of the photoreceptor 1Y is charged to a potential of -600 V to -800 V by the charging roller 2Y.

[0251] The photosensitive member 1Y is formed by laminating a photosensitive layer on a substrate having conductivity (for example, a volume resistivity of 1 × 10 -6 Ωcm or less at 20°C). This photosensitive layer generally has a high resistance (the resistance of a common resin), but has the property that the resistivity of the portion irradiated with the laser beam changes when irradiated with the laser beam. Therefore, according to the yellow image data sent from a control unit (not shown), the laser beam 3Y is irradiated from the exposure device 3 onto the surface of the charged photosensitive member 1Y. Thereby, an electrostatic image of a yellow image pattern is formed on the surface of the photosensitive member 1Y.

[0252] The electrostatic image is an image formed on the surface of the photosensitive member 1Y by charging, and is a so-called negative latent image. This negative latent image is formed as follows: the resistivity of the irradiated portion of the photosensitive layer is reduced by the laser beam 3Y, causing the charged charges on the surface of the photosensitive member 1Y to flow; on the other hand, the charges in the portion not irradiated with the laser beam 3Y remain, thereby forming this negative latent image.

[0253] The electrostatic image formed on the photosensitive member 1Y rotates to a preset development position as the photosensitive member 1Y rotates. And at this development position, the electrostatic image on the photosensitive member 1Y is developed into a toner image by the developing device 4Y for visualization.

[0254] Stored in the developing device 4Y is an electrostatic image developer containing, for example, at least yellow toner and a carrier. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, has a charge of the same polarity (negative polarity) as the charging charge on the photosensitive member 1Y, and is held on the developer roller (an example of a developer holding member). Thereafter, the surface of the photosensitive member 1Y passes through the developing device 4Y, whereby the yellow toner electrostatically adheres to the discharged latent image portion on the surface of the photosensitive member 1Y, and the latent image is developed using the yellow toner. The photosensitive member 1Y on which the yellow toner image is formed continues to rotate at a preset speed, and the toner image developed on the photosensitive member 1Y is transferred to a preset primary transfer position.

[0255] When the yellow toner image on the photosensitive member 1Y is transferred to the primary transfer position, a primary transfer bias is applied to the primary transfer roller 5Y, and the electrostatic force from the photosensitive member 1Y toward the primary transfer roller 5Y acts on the toner image, transferring the toner image on the photosensitive member 1Y to the intermediate transfer belt 20. The transfer bias applied at this time has a polarity (+) opposite to the polarity (-) of the toner, and is controlled to, for example, +10 μA by a control unit (not shown) in the first unit 10Y. The toner remaining on the photosensitive member 1Y is removed and recovered by the photosensitive member cleaning device 6Y.

[0256] The primary transfer biases applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M are also controlled in accordance with the first unit.

[0257] In this way, the intermediate transfer belt 20 on which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are multi-transferred in a superimposed manner.

[0258] The intermediate transfer belt 20 on which the four-color toner images have been multi-transferred through the first to fourth units reaches the secondary transfer section, which is composed of the intermediate transfer belt 20, a support roller 24 that is in contact with the inner surface of the intermediate transfer belt, and a secondary transfer roller (an example of a secondary transfer mechanism) 26 disposed on the image holding surface side of the intermediate transfer belt 20. On the other hand, the recording paper (an example of a recording medium) P is sent to the gap where the secondary transfer roller 26 contacts the intermediate transfer belt 20 at a preset timing by a supply member, and a secondary transfer bias is applied to the support roller 24. The transfer bias applied at this time has the same (-) polarity as the polarity (-) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P acts on the toner image, transferring the toner image on the intermediate transfer belt 20 onto the recording paper P. The secondary transfer bias at this time is determined based on the resistance detected by a resistance detection mechanism (not shown) that detects the resistance of the secondary transfer section, and the voltage is controlled.

[0259] The recording paper P on which the toner image has been transferred is sent into the crimping portion (biting portion) of a pair of fixing rollers in a fixing device (an example of a fixing mechanism) 28, and the toner image is fixed on the recording paper P to form a fixed image. The recording paper P on which the fixing of the color image has been completed is sent to the discharge section, ending a series of color image forming operations.

[0260] As the recording paper P for transferring the toner image, for example, ordinary paper used in electrophotographic copiers, printers, etc. can be cited. As the recording medium, in addition to the recording paper P, OHP transparent films, etc. can also be cited. In order to further improve the smoothness of the surface of the image after fixing, it is preferable that the surface of the recording paper P is also smooth. For example, coated paper obtained by coating the surface of ordinary paper with a resin or the like, art paper for printing, etc. are suitable for use.

[0261] <Processing cartridge, toner cartridge>

[0262] When the resin particles of the present embodiment are used as an electrostatic image developer, the processing cartridge is a processing cartridge that can be loaded and unloaded in an image forming apparatus, and includes a developing mechanism that stores an electrostatic image developer containing the resin particles of the present embodiment and develops an electrostatic image formed on the surface of an image holding body into a toner image.

[0263] The processing cartridge may be configured to include a developing mechanism and, if necessary, at least one of other mechanisms such as an image holding member, a charging mechanism, an electrostatic image forming mechanism, and a transfer mechanism.

[0264] An example of the processing cartridge is shown below, but it is not limited thereto. In the following description, the main parts shown in the drawings will be described, and other descriptions will be omitted.

[0265] Figure 4 It is a schematic configuration diagram showing an example of the processing cartridge used in the present embodiment.

[0266] Figure 4 The shown processing cartridge 200 is configured by integrally combining and holding a photosensitive member 107 (an example of an image holding member), a charging roller 108 (an example of a charging mechanism) provided around the photosensitive member 107, a developing device 111 (an example of a developing mechanism), and a photosensitive member cleaning device 113 (an example of a cleaning mechanism) through a housing 117 having a mounting rail 116 and an opening 118 for exposure, thereby forming an ink cartridge.

[0267] Figure 4 Among them, 109 represents an exposure device (an example of an electrostatic image forming mechanism), 112 represents a transfer device (an example of a transfer mechanism), 115 represents a fixing device (an example of a fixing mechanism), and 300 represents a recording paper (an example of a recording medium).

[0268] Next, the toner cartridge will be described.

[0269] The toner cartridge stores the resin particles of the present embodiment as toner for electrostatic image development and is detachable in an image forming apparatus. The toner cartridge stores replenishing toner to be supplied to a developing mechanism provided in the image forming apparatus.

[0270] Figure 3 The shown image forming apparatus is configured to be detachable with toner cartridges 8Y, 8M, 8C, and 8K. The developing devices 4Y, 4M, 4C, and 4K are connected to the corresponding color toner cartridges by toner supply tubes (not shown). In addition, when the toner stored in the toner cartridge is insufficient, the toner cartridge is replaced.

[0271] [Examples]

[0272] Examples of the present invention will be described below, but the present invention is not limited to the following examples. It should be noted that in the following description, unless otherwise specified, "parts" and "%" are all based on mass.

[0273] The confirmation of the sea-island structure in the toner particles was carried out by the above method.

[0274] (Example 1)

[0275] ><Production of Particles (1) Containing Fluorescent Colorant A>

[0276] · Polyester resin (manufactured by DIC Corporation, FINEDIC M-8020): 45 parts

[0277] · Blocked isocyanate (manufactured by Evonik Industries AG, VESTAGON BF1358): 45 parts

[0278] · Fluorescent dye (Basic Red 1:1, manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6G CP-N): 10 parts

[0279] The above components were heated and mixed (170 °C, 2 hours), coarsely pulverized using a Banbury mixer, and further pulverized to 1.9 μm using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles (1) containing fluorescent colorant A).

[0280] ><Preparation of Dispersion Liquid (1) of Particles Containing Fluorescent Colorant A>

[0281] · Particles (1) containing fluorescent colorant A: 200 parts

[0282] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid component concentration 20%)

[0283] · Pure water: 785 parts

[0284] The above materials were mixed, and a dispersion liquid (1) of particles containing fluorescent colorant A (solid component concentration 20%) was prepared using ULTRA-TURRAX.

[0285] ><Preparation of Dispersion Liquid (1) of Colorant B Particles>

[0286] · Magenta pigment (FASTOGEN SUPER MAGENTA R): 70 parts

[0287] · Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 30 parts (solid component concentration 20%)

[0288] · Ion-exchanged water: 200 parts

[0289] Mix the above materials and disperse them for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA). Add ion-exchanged water so that the solid content in the dispersion reaches 20% by mass to obtain a colorant B particle dispersion (1) in which colorant particles with a volume average particle diameter of 140 nm are dispersed.

[0290] <Preparation of resin particle dispersion (1)>

[0291] · Terephthalic acid: 30 parts by mole

[0292] · Fumaric acid: 70 parts by mole

[0293] · Bisphenol A ethylene oxide adduct: 5 parts by mole

[0294] · Bisphenol A propylene oxide adduct: 95 parts by mole

[0295] Put the above materials into a flask equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a distillation column. Raise the temperature to 220 °C over 1 hour, and add 1 part of tetraethoxy titanium to 100 parts of the above materials. While distilling off the generated water, raise the temperature to 230 °C over 30 minutes, and continue the dehydration condensation reaction at 230 °C for 1 hour, then cool the reaction product. Thus, a polyester resin with a weight average molecular weight of 18,000 and a glass transition temperature of 60 °C is obtained.

[0296] Put 40 parts of ethyl acetate and 25 parts of 2-butanol into a container equipped with a temperature control mechanism and a nitrogen replacement mechanism to prepare a mixed solvent, then slowly add 100 parts of the polyester resin to dissolve it. Add a 10% by mass ammonia water solution (an amount equivalent to 3 times the molar ratio of the acid value of the resin) and stir for 30 minutes. Then replace the inside of the container with dry nitrogen, keep the temperature at 40 °C, and while stirring the mixed solution, dropwise add 400 parts of ion-exchanged water at a rate of 2 parts per minute. After the dropping is completed, return to room temperature (20 °C to 25 °C), and while stirring, bubble with dry nitrogen for 48 hours to obtain a resin particle dispersion in which the content of ethyl acetate and 2-butanol is reduced to 1,000 ppm or less. Add ion-exchanged water to the above resin particle dispersion to adjust the solid content to 20% by mass to obtain the resin particle dispersion (1).

[0297] <Preparation of release agent particle dispersion (1)>

[0298] · Solid paraffin (manufactured by Nippon Seiro Co., Ltd., HNP-9): 100 parts

[0299] · Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 1 part

[0300] · Ion-exchanged water: 350 parts

[0301] Mix the above materials, heat to 100 °C, disperse using a homogenizer (IKA, product name ULTRA-TURRAX T50), and then perform dispersion treatment using a Manton Gaulin high-pressure homogenizer (Gaulin) to obtain a release agent particle dispersion liquid (1) (solid content: 20% by mass) in which release agent particles with a volume average particle diameter of 200 nm are dispersed.

[0302] <Production of toner particles (1)>

[0303] · Resin particle dispersion liquid (1): 241 parts

[0304] · Particle dispersion liquid (1) containing fluorescent colorant A: 175 parts

[0305] · Colorant B particle dispersion liquid (1): 9 parts

[0306] · Release agent particle dispersion liquid (1): 25 parts

[0307] · Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd.: NEOGEN RK, 20%): 10 parts

[0308] Put the above materials into a round stainless steel flask, adjust the pH to 3.5 by adding 0.1 N (= mol / L) nitric acid, and then add 30 parts of a nitric acid aqueous solution with a polyaluminum chloride concentration of 10% by mass. Then use a homogenizer (manufactured by IKA, product name ULTRA-TURRAX T50) to disperse at a liquid temperature of 30 °C, heat to 45 °C in a heating oil bath and hold for 30 minutes. Then add 50 parts of resin particle dispersion liquid (1) and hold for 1 hour. Add 0.1 N sodium hydroxide aqueous solution to adjust the pH to 8.5, then heat to 84 °C and hold for 2.5 hours. Then cool to 20 °C at a rate of 20 °C / minute, filter out the solid components, wash thoroughly with ion-exchanged water, and dry to obtain toner particles (1). The volume average particle diameter of toner particles (1) is 5.8 μm.

[0309] <Production of carrier 1>

[0310] · Ferrite particles (average particle diameter 35 μm): 100 parts

[0311] · Toluene: 14 parts

[0312] · Polymethyl methacrylate (MMA, weight average molecular weight 75,000): 5 parts

[0313] · Carbon black: 0.2 parts (VXC-72, manufactured by Cabot, volume resistivity: 100 Ω·cm or less)

[0314] Disperse the above materials except for the ferrite particles using a sand mill to prepare a dispersion liquid. Load the dispersion liquid and the ferrite particles into a vacuum degassing kneader, and under stirring, reduce the pressure to dry it, thereby obtaining Carrier 1.

[0315] <Manufacture of toner

[0316] With respect to 100 parts by mass of the obtained toner particles (1), 1.5 parts by mass of hydrophobic silica (manufactured by NIPPON AEROSIL Co., Ltd., RY50) and 1.0 part by mass of hydrophobic titanium oxide (manufactured by NIPPON AEROSIL Co., Ltd., T805) were mixed using a sample mill at 10,000 rpm (revolutions per minute) for 30 seconds for blending. Thereafter, screening was performed using a vibrating sieve with a mesh size of 45 μm to prepare Toner 1 (toner for electrostatic image development). The volume average particle diameter of the obtained Toner 1 was 5.8 μm.

[0317] <Manufacture of electrostatic image developer

[0318] Mix 8 parts of toner and 92 parts of carrier using a V-type blender to prepare Developer 1 (electrostatic image developer).

[0319] (Example 2)

[0320] <Manufacture of particles (2) containing fluorescent colorant A

[0321] · Terephthalic acid: 30 parts by mole

[0322] · Fumaric acid: 70 parts by mole

[0323] · Bisphenol A ethylene oxide adduct: 5 parts by mole

[0324] · Bisphenol A propylene oxide adduct: 95 parts by mole

[0325] Put the above materials into a flask equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a distillation column. Raise the temperature to 220 °C over 1 hour, and add 1 part of tetraethoxysilane with respect to 100 parts of the above materials. While distilling off the generated water, raise the temperature to 230 °C over 30 minutes, and after continuing the dehydration condensation reaction at 230 °C for 1 hour, cool the reaction product. Thus, a polyester resin with a weight average molecular weight of 18,000 and a glass transition temperature of 60 °C is obtained.

[0326] · The above polyester resin: 93 parts

[0327] · Fluorescent dye (Basic Red 1:1, manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6GCP-N): 7 parts

[0328] Heat and mix the above components (at 170 °C for 2 hours), and perform rough crushing using a Banbury mixer. Further crush to 1.0 μm using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles (2) containing a fluorescent colorant A).

[0329] <Preparation of the particle dispersion liquid (2) containing a fluorescent colorant A>

[0330] · Particles (2) containing a fluorescent colorant A: 200 parts

[0331] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid component concentration 20%)

[0332] · Pure water: 785 parts

[0333] Mix the above components and crush to 0.2 μm using a continuous Key Mill (KMC-3) to prepare a particle dispersion liquid (2) containing a fluorescent colorant A (solid component concentration 20%).

[0334] <Preparation of the particles (2) containing a colorant B>

[0335] · Polyester resin (manufactured by DIC Corporation, FINEDIC M-8020): 47.5 parts

[0336] · Blocked isocyanate (manufactured by Evonik Corporation, VESTAGON BF1358): 47.5 parts

[0337] · Magenta pigment (FASTOGEN SUPER MAGENTA R): 5 parts

[0338] Heat and mix the above components (at 170 °C for 2 hours), perform rough crushing using a Banbury mixer, and further crush to 1.9 μm using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles (2) containing a colorant B).

[0339] <Preparation of the particle dispersion liquid (2) containing a colorant B>

[0340] · Particles (2) containing a colorant B: 200 parts

[0341] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid component concentration 20%)

[0342] · Pure water: 785 parts

[0343] Mix the above components to prepare a particulate dispersion (2) containing colorant B (solid content concentration: 20%) using ULTRA-TURRAX.

[0344] <Preparation of toner particles (2)>

[0345] · Particulate dispersion (2) containing fluorescent colorant A: 250 parts

[0346] · Particulate dispersion (2) of colorant B: 175 parts

[0347] · Particulate dispersion (1) of release agent: 25 parts

[0348] · Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.: NEOGEN RK, 20%): 10 parts

[0349] Put the above materials into a round stainless-steel flask, add 0.1 N (= mol / L) nitric acid, adjust the pH to 3.5, and then add 30 parts of an aqueous nitric acid solution with a polyaluminum chloride concentration of 10% by mass. Next, disperse the mixture at a liquid temperature of 30 °C using a homogenizer (manufactured by IKA Co., Ltd., trade name: ULTRA-TURRAX T50), heat it to 45 °C in a heating oil bath and hold for 30 minutes. Thereafter, add 50 parts of a resin particulate dispersion (1) and hold for 1 hour. Adjust the pH to 8.5 by adding 0.1 N aqueous sodium hydroxide solution, then heat to 84 °C and hold for 2.5 hours. Then cool it to 20 °C at a rate of 20 °C / minute, filter out the solid components, wash them thoroughly with ion-exchanged water, and dry them to obtain toner particles (2). The volume average particle diameter of the toner particles (2) is 5.8 μm.

[0350] Except for using toner particles (2) instead of toner particles (1), an electrostatic image developing toner and an electrostatic image developer are produced in the same manner as in Example 1.

[0351] (Example 3)

[0352] In Example 3, the pigment of the colorant in Example 1 was changed to PR202 (manufactured by BASF Co., Ltd., Cinquasia Magenta L 4530). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1.

[0353] (Example 4)

[0354] In Example 4, the pigment of the colorant in Example 2 was changed to PR202 (manufactured by BASF Co., Ltd., Cinquasia Magenta L 4530). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2.

[0355] (Example 5)

[0356] In Example 5, the pigment of the colorant in Example 1 was changed to PR282 (manufactured by BASF, Cinquasia Magenta L 4400), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0357] (Example 6)

[0358] In Example 6, the pigment of the colorant in Example 2 was changed to PR282 (manufactured by BASF, Cinquasia Magenta L 4400), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0359] (Example 7)

[0360] In Example 7, the pigment of the colorant in Example 1 was changed to a PR122 / PV19 solid solution pigment (manufactured by DIC Corporation, FASTOGEN SUPER MAGENTA RE-05), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0361] (Example 8)

[0362] In Example 8, the pigment of the colorant in Example 2 was changed to a PR122 / PV19 solid solution pigment (manufactured by DIC Corporation, FASTOGEN SUPER MAGENTA RE-05), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0363] (Example 9)

[0364] In Example 9, the pigment of the colorant in Example 1 was changed to PR238 (manufactured by Clariant, Permanent Carmine F5B), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0365] (Example 10)

[0366] In Example 10, the pigment of the colorant in Example 2 was changed to PR238 (manufactured by Clariant, Permanent Carmine F5B), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0367] (Example 11)

[0368] In Example 11, the pigment of the colorant in Example 1 was changed to PR269 (manufactured by Tokyo Ink Co., Ltd., Pigment Red 269), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0369] (Example 12)

[0370] In Example 12, the pigment of the colorant in Example 2 was changed to PR269 (manufactured by Tokyo Ink Co., Ltd., Pigment Red 269), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0371] (Example 13)

[0372] In Example 13, the pigment of the colorant in Example 1 was changed to PR169 (manufactured by BASF, Fanal Pink D4810), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0373] (Example 14)

[0374] In Example 14, the pigment of the colorant in Example 2 was changed to PR169 (manufactured by BASF, Fanal Pink D4810), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0375] (Example 15)

[0376] In Example 15, the pigment of the colorant in Example 1 was changed to PR81:2 (manufactured by BASF, Fanal PinkD 4830), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0377] (Example 16)

[0378] In Example 16, the pigment of the colorant in Example 2 was changed to PR81:2 (manufactured by BASF, Fanal PinkD 4830), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 2 except for this change.

[0379] (Example 17)

[0380] In Example 17, using the method of Example 1, the concentration of the fluorescent colorant was adjusted to the composition of Table 2, and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1 except for this change.

[0381] (Example 18)

[0382] In Example 18, using the method of Example 2, the concentration of the fluorescent colorant was adjusted to the composition shown in Table 2, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 2, except for this.

[0383] (Example 19)

[0384] In Example 19, using the method of Example 1, the concentration of the fluorescent colorant was adjusted to the composition shown in Table 2, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 1, except for this.

[0385] (Example 20)

[0386] In Example 20, using the method of Example 2, the concentration of the fluorescent colorant was adjusted to the composition shown in Table 2, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 2, except for this.

[0387] (Example 21)

[0388] In Example 21, using the method of Example 1, the concentration of the colorant was adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 1, except for this.

[0389] (Example 22)

[0390] In Example 22, using the method of Example 2, the concentration of the colorant was adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 2, except for this.

[0391] (Example 23)

[0392] In Example 23, using the method of Example 1, the concentration of the colorant was adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 1, except for this.

[0393] (Example 24)

[0394] In Example 24, using the method of Example 2, the concentration of the colorant was adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 2, except for this.

[0395] (Example 25)

[0396] In Example 25, using the method of Example 1, the concentrations of the fluorescent colorant and the colorant were adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 1, except for this.

[0397] (Example 26)

[0398] In Example 26, using the method of Example 2, the concentrations of the fluorescent colorant and the colorant were adjusted to the composition shown in Table 3, and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 2 except for this.

[0399] (Example 27)

[0400] In Example 27, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 25 except for this.

[0401] (Example 28)

[0402] In Example 28, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 26 except for this.

[0403] (Example 29)

[0404] In Example 29, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR202 (manufactured by BASF, Cinquasia Magenta L 4530), and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 25 except for this.

[0405] (Example 30)

[0406] In Example 30, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR202 (manufactured by BASF, Cinquasia Magenta L 4530), and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 26 except for this.

[0407] (Example 31)

[0408] In Example 31, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR282 (manufactured by BASF, Cinquasia Magenta L 4400), and an electrostatic image developing toner and an electrostatic image developer were prepared in the same manner as in Example 25 except for this.

[0409] (Example 32)

[0410] In Example 32, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR282 (manufactured by BASF Corporation, Cinquasia Magenta L 4400). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0411] (Example 33)

[0412] In Example 33, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to a PR122 / PV19 solid solution pigment (manufactured by DIC Corporation, FASTOGEN SUPERMAGENTA RE-05). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0413] (Example 34)

[0414] In Example 34, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to a PR122 / PV19 solid solution pigment (manufactured by DIC Corporation, FASTOGEN SUPERMAGENTA RE-05). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0415] (Example 35)

[0416] In Example 35, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR238 (manufactured by Clariant Corporation, Permanent Carmine F5B). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0417] (Example 36)

[0418] In Example 36, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR238 (manufactured by Clariant Corporation, Permanent Carmine F5B). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0419] (Example 37)

[0420] In Example 37, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR269 (manufactured by Tokyo Ink Co., Ltd., Pigment Red 269). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0421] (Example 38)

[0422] In Example 38, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR269 (manufactured by Tokyo Ink Co., Ltd., Pigment Red 269). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0423] (Example 39)

[0424] In Example 39, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR169 (manufactured by BASF, Fanal Pink D 4810). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0425] (Example 40)

[0426] In Example 40, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR169 (manufactured by BASF, Fanal Pink D 4810). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0427] (Example 41)

[0428] In Example 41, the fluorescent colorant of Example 25 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR81:2 (manufactured by BASF, Fanal Pink D 4830). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0429] (Example 42)

[0430] In Example 42, the fluorescent colorant of Example 26 was changed to Basic Violet 11:1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine A), and the colorant was changed to PR81:2 (manufactured by BASF, Fanal Pink D 4830). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 26.

[0431] (Example 43)

[0432] In Example 43, the fluorescent colorant of Example 33 was changed to Basic Red 1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6GCP). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 33.

[0433] (Example 44)

[0434] In Example 44, the fluorescent colorant of Example 34 was changed to Basic Red 1 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6GCP). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 34.

[0435] (Example 45)

[0436] In Example 45, the fluorescent colorant of Example 33 was changed to Basic Violet 10 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine B gran.). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 33.

[0437] (Example 46)

[0438] In Example 46, the fluorescent colorant of Example 34 was changed to Basic Violet 10 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine B gran.). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 34.

[0439] (Example 47)

[0440] In Example 47, the fluorescent colorant of Example 33 was changed to Solvent Red 49 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine B base). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 33.

[0441] (Example 48)

[0442] In Example 48, the fluorescent colorant of Example 34 was changed to Solvent Red 49 (manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine B base). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 34.

[0443] (Example 49)

[0444] In Example 49, the fluorescent colorant of Example 25 was changed to Basic Yellow 40 (Neelikon Food Dyes And Chemicals, Neeliglow Yellow 40), and the colorant was changed to PY74 (manufactured by Clariant Corporation, HANSABRILLIANT YELLOW 2GX 70). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 25.

[0445] (Example 50)

[0446] In Example 50, the fluorescent colorant of Example 26 was changed to Basic Yellow 40 (Neelikon Food Dyes And Chemicals, Neeliglow Yellow 40), and the colorant was changed to PY74 (manufactured by Clariant Corporation, HANSABRILLIANT YELLOW 2GX 70). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 26.

[0447] (Example 51)

[0448] In Example 51, the fluorescent colorant of Example 25 was changed to Solvent Green 7 (Neelikon Food Dyes And Chemicals, Neelink Green 7), and the colorant was changed to PG36 (manufactured by DIC Corporation, FASTOGEN GREEN 2YK). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 25.

[0449] (Example 52)

[0450] In Example 52, the fluorescent colorant of Example 26 was changed to Solvent Green 7 (Neelikon Food Dyes And Chemicals, Neelink Green 7), and the colorant was changed to PG36 (manufactured by DIC Corporation, FASTOGEN GREEN 2YK). Except for this, a toner for electrostatic image development and an electrostatic image developer were produced in the same manner as in Example 26.

[0451] (Example 53)

[0452] In Example 53, the fluorescent colorant of Example 25 was changed to Solvent Orange 63 (Neelikon Food Dyes And Chemicals, Neelglow Orange 63), and the colorant was changed to PO43 (manufactured by Clariant, Hostaperm Orange GR). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0453] (Example 54)

[0454] In Example 54, the fluorescent colorant of Example 26 was changed to Solvent Orange 63 (Neelikon Food Dyes And Chemicals, Neelglow Orange 63), and the colorant was changed to PO43 (manufactured by Clariant, Hostaperm Orange GR). Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 26.

[0455] (Example 55)

[0456] In Example 55, the fluorescent colorant particles of Example 25 were pulverized to 1.4 μm. Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0457] (Example 56)

[0458] In Example 56, the colorant particles of Example 25 were pulverized to 1.4 μm. Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0459] (Example 57)

[0460] In Example 57, the fluorescent colorant particles of Example 25 were pulverized to 2.5 μm. Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0461] (Example 58)

[0462] In Example 58, the colorant particles of Example 25 were pulverized to 2.5 μm. Except for this, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 25.

[0463] (Example 59)

[0464] <Production of Styrene - Acrylic Resin Particle Dispersion (1)>:

[0465] · Styrene (manufactured by Wako Pure Chemical Industries, Ltd.): 65.0 parts

[0466] · n-Butyl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.): 30.0 parts

[0467] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 1.0 part

[0468] · Polymerization initiator (ammonium persulfate): 1.0 part

[0469] · DIW: 400 parts

[0470] The above materials were mixed in a flask and emulsified for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA). Then, after replacing the nitrogen in the flask, the solution in the flask was heated to 85 °C with stirring in a water bath, and emulsion polymerization was carried out for 5 hours in this state. After that, it was cooled to 30 °C to obtain a styrene-acrylic resin particle dispersion (1) with a solid component concentration of 20% and a volume average particle diameter of 180 nm.

[0471] <Production of Particles (59) Containing Fluorescent Colorant A>

[0472] · The above acrylic resin after removing impurities using a dialysis membrane and drying: 45 parts

[0473] · Blocked isocyanate (manufactured by Evonik, VESTAGON BF1358): 45 parts

[0474] · Fluorescent dye (Basic Red 1:1, manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6G CP-N): 10 parts

[0475] The above components were heated and mixed (170 °C, 2 hours), coarsely pulverized using a Banbury mixer, and further pulverized to 1.8 μm using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles (59) containing fluorescent colorant A).

[0476] <Preparation of Particle Dispersion (59) Containing Fluorescent Colorant A>

[0477] · Particles (59) containing fluorescent colorant A: 200 parts

[0478] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid component concentration 20%)

[0479] · Pure water: 785 parts

[0480] Mix the above components to prepare a particulate dispersion (59) containing a fluorescent colorant A (solid component concentration: 20%) using an ULTRA-TURRAX.

[0481] <Production of toner particles (59)>

[0482] · Styrene acrylic resin particle dispersion (1): 346 parts

[0483] · Particulate dispersion (59) containing fluorescent colorant A: 75 parts

[0484] · Colorant B particle dispersion (1): 4 parts

[0485] · Release agent particle dispersion (1): 25 parts

[0486] · Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.: NEOGEN RK, 20%): 10 parts

[0487] Put the above materials into a round stainless steel flask, add 0.1 N (= mol / L) nitric acid to adjust the pH to 3.5, and then add 30 parts of an aqueous nitric acid solution with a polyaluminum chloride concentration of 10% by mass. Next, disperse the mixture at a liquid temperature of 30 °C using a homogenizer (manufactured by IKA Co., Ltd., trade name: ULTRA-TURRAX T50), and then heat it to 45 °C in a heating oil bath and hold for 30 minutes. Thereafter, add 50 parts of the styrene acrylic resin particle dispersion (1) and hold for 1 hour. Add 0.1 N aqueous sodium hydroxide solution to adjust the pH to 8.5, and then heat to 84 °C and hold for 2.5 hours. Then cool it to 20 °C at a rate of 20 °C / minute, filter out the solid components, wash them thoroughly with ion-exchanged water, and dry them to obtain toner particles (59). The volume average particle diameter of the toner particles (59) is 5.8 μm.

[0488] An electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Example 1, except that toner particles (59) were used instead of toner particles (1).

[0489] (Example 60)

[0490] <Production of particles (60) containing fluorescent colorant A>

[0491] · Styrene (manufactured by Wako Pure Chemical Industries, Ltd.): 65.0 parts

[0492] · n-Butyl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.): 30.0 parts

[0493] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 1.0 part

[0494] · Polymerization initiator (ammonium persulfate): 1.0 part

[0495] · DIW: 400 parts

[0496] Mix the above materials in a flask and emulsify them for 10 minutes using a homogenizer (ULTRA-TURRAX T50 manufactured by IKA). Then, after purging the nitrogen in the flask, heat the solution in the flask to 85 °C with stirring using a water bath, and carry out emulsion polymerization for 5 hours in this state. After that, cool it to 30 °C to obtain a styrene-acrylic resin particle dispersion (1) with a solid content concentration of 20% and a volume average particle diameter of 180 nm.

[0497] · The material obtained by removing impurities from the styrene-acrylic resin particle dispersion (1) using a dialysis membrane and drying it: 98.22 parts

[0498] · Fluorescent dye (Basic Red 1:1, manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6GCP-N): 1.78 parts

[0499] Heat and mix the above components (170 °C, 2 hours), coarsely crush them using a Banbury mixer, and further crush them to 1.0 μm using a crusher AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles (60) containing fluorescent colorant A).

[0500] <Preparation of particle dispersion (60) containing fluorescent colorant A>

[0501] · Particles (60) containing fluorescent colorant A: 200 parts

[0502] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid content concentration 20%)

[0503] · Pure water: 785 parts

[0504] Mix the above components and crush them to 0.2 μm using a continuous Key Mill (KMC-3) to prepare a particle dispersion (60) containing fluorescent colorant A (solid content concentration 20%).

[0505] <Preparation of particles (60) containing colorant B>

[0506] · The material obtained by removing impurities from the styrene-acrylic resin particle dispersion (1) using a dialysis membrane and drying it: 47.5 parts

[0507] · Blocked isocyanate (manufactured by Evonik Corporation, VESTAGON BF1358): 47.5 parts

[0508] · Magenta pigment (FASTOGEN SUPER MAGENTA R): 5 parts

[0509] Heat and mix the above components (170 °C, 2 hours), coarsely crush using a Banbury mixer, and further crush to 1.9 μm using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain polyester polyurethane resin colored particles (particles containing colorant B (60)).

[0510] <Preparation of dispersion liquid of particles containing colorant B (60)>

[0511] · Particles containing colorant B (60): 200 parts

[0512] · Surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., NEOGEN RK): 15 parts (solid component concentration 20%)

[0513] · Pure water: 785 parts

[0514] Mix the above components and use ULTRA-TURRAX to prepare a dispersion liquid of particles containing colorant B (60) (solid component concentration 20%).

[0515] <Preparation of toner particles (60)>

[0516] · Dispersion liquid of particles containing fluorescent colorant A (60): 421 parts

[0517] · Dispersion liquid of particles containing colorant B (60): 4 parts

[0518] · Release agent particle dispersion liquid (1): 25 parts

[0519] · Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd.: NEOGEN RK, 20%): 10 parts

[0520] Put the above materials into a round stainless steel flask, adjust the pH to 3.5 by adding 0.1 N (= mol / L) nitric acid, and then add 30 parts of a nitric acid aqueous solution with a polyaluminum chloride concentration of 10% by mass. Then use a homogenizer (manufactured by IKA Corporation, trade name ULTRA-TURRAX T50) to disperse at a liquid temperature of 30 °C, and then heat to 45 °C in a heating oil bath and hold for 30 minutes. Subsequently, add 50 parts of a styrene-acrylic resin particle dispersion liquid (1) and hold for 1 hour. Adjust the pH to 8.5 by adding 0.1 N sodium hydroxide aqueous solution, and then heat to 84 °C and hold for 2.5 hours. Then cool to 20 °C at a rate of 20 °C / minute, filter out the solid components, wash thoroughly with ion-exchanged water, and dry to obtain toner particles (60). The volume average particle diameter of the toner particles (60) is 5.7 μm.

[0521] An electrophotographic developer and an electrophotographic toner are produced in the same manner as in Example 1, except that toner particles (60) are used instead of toner particles (1).

[0522] (Comparative Example 1: Uniform dispersion)

[0523] · Substance obtained by removing impurities from the resin particle dispersion (1) using a dialysis membrane and drying: 48.7 parts

[0524] · Polyester resin (manufactured by DIC Corporation, FINEDIC M-8020): 16 parts

[0525] · Blocked isocyanate (manufactured by Evonik Corporation, VESTAGON BF1358): 16 parts

[0526] · Fluorescent dye (Basic Red 1:1, manufactured by Taoka Chemical Industry Co., Ltd., Rhodamine 6GCP-N): 3.5 parts

[0527] · Magenta pigment (FASTOGEN SUPER MAGENTA R): 0.8 parts

[0528] · Release agent (solid paraffin (manufactured by Nippon Seiro Co., Ltd., HNP-9)): 5 parts

[0529] The above components are heated and mixed (170 °C, 2 hours), coarsely pulverized using a Banbury mixer, and further pulverized using a pulverizer AFG100 (manufactured by Hosokawa Micron Corporation) to obtain toner particles. The volume average diameter of the toner particles is 5.5 μm.

[0530] · The above toner particles: 90 parts

[0531] · Substance obtained by removing impurities from the resin particle dispersion (1) using a dialysis membrane and drying: 10 parts

[0532] The above components are mixed using a Nobilta 300 (manufactured by Hosokawa Micron Corporation) to obtain toner particles coated with a shell layer. The volume average diameter of the toner particles is 5.9 μm.

[0533] (Comparative Example 2)

[0534] In Comparative Example 2, an electrophotographic developer and an electrophotographic toner are produced in the same manner as in Comparative Example 1, except that the magenta pigment is changed to PR202 (manufactured by BASF Corporation, Cinquasia Magenta L4530).

[0535] (Comparative Example 3)

[0536] In Comparative Example 3, an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except that the magenta pigment was changed to PR282 (manufactured by BASF, Cinquasia Magenta L4400).

[0537] (Comparative Example 4)

[0538] In Comparative Example 4, the magenta pigment was changed to a PR122 / PV19 solid solution pigment (manufactured by DIC Corporation, FASTOGEN SUPER MAGENTA RE-05), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except for this change.

[0539] (Comparative Example 5)

[0540] In Comparative Example 5, the magenta pigment was changed to PR238 (manufactured by Clariant, Permanent Carmine F5B), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except for this change.

[0541] (Comparative Example 6)

[0542] In Comparative Example 6, the magenta pigment was changed to PR269 (manufactured by Tokyo Ink Co., Ltd., Pigment Red 269), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except for this change.

[0543] (Comparative Example 7)

[0544] In Comparative Example 7, the magenta pigment was changed to PR169 (manufactured by BASF, Fanal Pink D 4810), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except for this change.

[0545] (Comparative Example 8)

[0546] In Comparative Example 8, the magenta pigment was changed to PR81:2 (manufactured by BASF, Fanal Pink D 4830), and an electrostatic image developing toner and an electrostatic image developer were produced in the same manner as in Comparative Example 1, except for this change.

[0547] The following evaluations were performed using the electrostatic image developing toners and electrostatic image developers of Examples 1 to 60 and Comparative Examples 1 to 8 obtained. The evaluation results are summarized in Tables 1 to 7.

[0548] <Fluorescence intensity evaluation>

[0549] The following operations and image formation were carried out in an environment of temperature 23°C / humidity 50% RH.

[0550] As an image forming apparatus for forming an evaluation image, an ApeosPort IV C4470 manufactured by Fuji Xerox Co., Ltd. was prepared. The developer was loaded into the developing unit, and the replenishing toner (the same toner as the toner contained in the developer) was loaded into the toner cartridge. Then, an image with an image area ratio of 100% and a size of 5 cm × 5 cm was formed on OS coated paper (basis weight: 127 g / m 2 ) manufactured by Fuji Xerox Co., Ltd., output at a fixing temperature of 170°C, and fluorescence intensity evaluation was performed.

[0551] Regarding the fluorescence intensity, the spectral reflectance in the visible light region was measured using an X-Rite (manufactured by X-Rite Inc.), and the fluorescence peak intensity at the spectral reflectance was used as the fluorescence intensity.

[0552] A: 112% or more

[0553] B: More than 108% and less than 112%

[0554] C: More than 104% and less than 108%

[0555] D: Less than 104%

[0556]

[0557]

[0558]

[0559]

[0560]

[0561]

[0562]

[0563] From the results shown in Tables 1 to 7 above, it can be seen that the fluorescence intensity of the image obtained from the resin particles (toner for electrostatic image development) of this example is higher than that of the resin particles (toner for electrostatic image development) of the comparative example.

[0564] (Example 61)

[0565] - Production of Coated Product -

[0566] On a 10 cm × 10 cm quadrilateral test plate of a zinc phosphate-treated steel sheet, a corona gun manufactured by Asahi Suntec Co., Ltd. was used to slide the corona gun up, down, left, and right at a distance of 30 cm from the front surface in such a way that the coating film thickness was 30 μm or more and 50 μm or less to coat the resin particles of Example 1. After that, baking was performed under baking conditions of 150 °C for 5 minutes to produce a coated product.

[0567] In the produced coated product, powder adhered to the coated article (zinc phosphate-treated steel sheet), and it was confirmed that coating was performed.

[0568] Symbol Explanation

[0569] 1Y, 1M, 1C, 1K Photoconductor (an example of an image holding member)

[0570] 2Y, 2M, 2C, 2K Charging roller (an example of a charging mechanism)

[0571] 3 Exposure device (an example of an electrostatic image forming mechanism)

[0572] 3Y, 3M, 3C, 3K Laser line

[0573] 4Y, 4M, 4C, 4K Developing device (an example of a developing mechanism)

[0574] 5Y, 5M, 5C, 5K Primary transfer roller (an example of a primary transfer mechanism)

[0575] 6Y, 6M, 6C, 6K Photoconductor cleaning device (an example of an image holding member cleaning unit)

[0576] 8Y, 8M, 8C, 8K Toner cartridge

[0577] 10Y, 10M, 10C, 10K Image forming unit

[0578] 20 Intermediate transfer belt (an example of an intermediate transfer member)

[0579] 22 Driving roller

[0580] 24 Support roller

[0581] 26 Secondary transfer roller (an example of a secondary transfer mechanism)

[0582] 28 Fixing device (an example of a fixing mechanism)

[0583] 30 Intermediate transfer belt cleaning device (an example of an intermediate transfer member cleaning unit)

[0584] P Recording paper (an example of a recording medium)

[0585] 50 Recording medium

[0586] 52 toner image

[0587] 54 area RA

[0588] 56 area RB

[0589] 58 color mixing area

[0590] 107 photoreceptor (an example of an image holding member)

[0591] 108 charging roller (an example of a charging mechanism)

[0592] 109 exposure device (an example of an electrostatic image forming mechanism)

[0593] 111 developing device (an example of a developing mechanism)

[0594] 112 transfer device (an example of a transfer mechanism)

[0595] 113 photoreceptor cleaning device (an example of an image holding member cleaning unit)

[0596] 115 fixing device (an example of a fixing mechanism)

[0597] 116 mounting rail

[0598] 117 housing

[0599] 118 opening for exposure

[0600] 200 process cartridge

[0601] 300 recording paper (an example of a recording medium)

Claims

1. A resin particle, which is a resin particle containing a binder resin, a fluorescent colorant A, and a colorant B other than the above fluorescent colorant A, wherein, there are regions RA and RB in the above resin particle, the region RA is a region where the content of the above fluorescent colorant A is more than that of the colorant B, and the region RB is a region where the content of the colorant B is more than that of the above fluorescent colorant A, the above region RA and the above region RB form a sea-island structure, the above region RA forms the island structure of the above sea-island structure, and the above region RB forms the sea structure of the above sea-island structure, in the above sea-island structure, a polyurethane resin is included as the binder resin in the island structure, and a styrene-acrylic copolymer or a polyester resin is included as the binder resin in the sea structure, the ratio of the volume average particle diameter VI of the island structure in the above sea-island structure to the volume average particle diameter VT of the above resin particle, that is, the value of VI / VT, is 0.15 or more and 0.80 or less.

2. The resin particle according to claim 1, wherein, the ratio of the volume average particle diameter VI of the island structure in the above sea-island structure to the volume average particle diameter VT of the above resin particle, that is, the value of VI / VT, is 0.30 or more and 0.65 or less.

3. The resin particle according to claim 1, wherein, the above fluorescent colorant A is a fluorescent dye.

4. The resin particle according to claim 3, wherein, the above fluorescent dye includes a fluorescent dye having a maximum fluorescence wavelength in the range of 580 nm to 650 nm.

5. The resin particle according to any one of claims 1 to 4, wherein, the above colorant B contains a magenta pigment.

6. The resin particle according to claim 5, wherein, the above colorant B contains two or more magenta pigments.

7. The resin particle according to claim 1, wherein, the above region RA includes: a region where the content of the above fluorescent colorant A is 80% by mass or more relative to the total mass of the colorants contained.

8. The resin particle according to claim 1, wherein, the above region RA includes: a region where the content of the above fluorescent colorant A is 90% by mass or more relative to the total mass of the colorants contained.

9. The resin particle according to claim 1, wherein, the above region RA includes: a region containing only the above fluorescent colorant A as the colorant contained.

10. The resin particle according to claim 1, wherein, the above region RB includes: a region where the content of the above colorant B is 80% by mass or more relative to the total mass of the colorants contained.

11. The resin particle according to claim 1, wherein, the above region RB includes: a region where the content of the above colorant B is 90% by mass or more relative to the total mass of the colorants contained.

12. The resin particle according to claim 1, wherein, the above region RB includes: a region containing only the above colorant B as the colorant contained.

13. The resin particle according to claim 1, wherein, the above region RA includes: a region where the content of the above fluorescent colorant A is 80% by mass or more relative to the total mass of the colorants contained, and The above-mentioned region RB includes: a region in which the content of the above-mentioned colorant B is 80% by mass or more relative to the total mass of the colorants contained therein.

Images