Toner group, developer group, toner cartridge group, processing cartridge group, printing material manufacturing apparatus, and printing material manufacturing method

Abstract

The present invention provides a toner set, a developer set, a toner cartridge set, a processing cartridge set, a printing material manufacturing apparatus, and a printing material manufacturing method. A toner set includes: a color toner and a transparent toner having pressure transferability. When the tanδ of the color toner at 100°C is set as tanδ1 and the tanδ of the transparent toner at 100°C is set as tanδ2, tanδ1 is 1.0 or more and 4.0 or less, and tanδ1 and tanδ2 satisfy the following formula 1. Formula 1: 1.2 ≤ tanδ1 / tanδ2 ≤ 3.0.

Description

[0001] Public background 1) Technical Field

[0003] The present application relates to a toner set, a developer set, a toner cartridge set, a process cartridge set, a printed product manufacturing apparatus, and a printed product manufacturing method.

[0004] 2) Related technologies

[0005] Japanese Patent Application Laid-Open No. 2008-173917 describes a pressure-bonded sheet manufacturing apparatus that uses powdered toner particles as an adhesive to bond sheets, and is characterized in that it has fixing sections at two locations for thermally fixing the adhesive to the sheet.

[0006] Japanese Patent Publication No. 2008-155412 discloses a press-bonded printed matter production device, which is a press-bonded printed matter production device that applies a powder adhesive to a sheet by transfer using an electronic photographic method and press-bonds the confidential information printing surface coated with the powder adhesive, and is characterized in that it comprises: a first image forming unit that transfers confidential information formed by a toner onto the back side of the sheet; a second image forming unit that transfers the powder adhesive onto the transfer surface of the confidential information; a first heating and pressing device, It temporarily fixes the powder adhesive while fixing the confidential information on the sheet; a conveying mechanism that reverses and conveys the sheet; a third image forming unit that transfers variable information on the surface of the sheet; a second heating and pressing device that fixes the variable information on the surface of the sheet; a first folding device that concavely folds the back of the sheet from the center; and a third heating and pressing device that formally fixes the temporarily fixed surface of the powder adhesive by heat and pressure to perform compression bonding, thereby producing a folded and compressed printed matter that can be delivered.

[0007] Japanese Patent Laid-Open No. 2013-015664 discloses an image forming apparatus including a plurality of image forming units and a fixing unit. Each image forming unit includes an image carrier, a developing unit, a transfer unit, and an image carrier cleaning unit. The toner used in the developing unit is a pressure transfer resin toner containing a pressure transfer resin or a thermoplastic resin toner containing a thermoplastic resin. Both the pressure transfer resin toner and the thermoplastic resin toner are used in the developing units included in at least one or more image forming units. The fixing unit further includes a pressure fixing nip portion having a fixing nip and a heat fixing nip portion having a fixing nip. The pressure fixing nip portion fixes the pressure transfer resin toner forming a toner image transferred onto a recording medium to the recording medium, and the heat fixing nip portion fixes the thermoplastic resin toner forming a toner image transferred onto the recording medium to the recording medium. The relationship between the temperature Tb and pressure Pb under the fixing conditions of the pressure transfer resin toner in the pressure fixing nip portion and the temperature Ta and pressure Pa under the fixing conditions of the thermoplastic resin toner in the heat fixing nip portion is Tb < Ta and Pb > Pa. SUMMARY OF THE INVENTION

[0008] An object of the present application is to provide a toner set that achieves both suppression of offset during heat fixing and crimpability as compared with cases where tan δ1 is less than 1.0 or greater than 4.0 or where tan δ1 / tan δ2 is less than 1.2 or greater than 3.0.

[0009] According to a first aspect of the present application, there is provided a toner set having: a color toner, and a transparent toner having pressure transferability.

[0010] When tan δ of the color toner at 100°C is defined as tan δ1 and tan δ of the transparent toner at 100°C is defined as tan δ2, tan δ1 is 1.0 or more and 4.0 or less, and tan δ1 and tan δ2 satisfy the following formula (1).

[0011] Formula (1): 1.2 ≤ tan δ1 / tan δ2 ≤ 3.0

[0012] According to a second aspect of the present application, tan δ1 is 1.5 or more and 3.5 or less.

[0013] According to a third aspect of the present application, tan δ1 and tan δ2 satisfy the following formula (2).

[0014] Formula (2): 1.5 ≤ tan δ1 / tan δ2 ≤ 2.9

[0015] According to the fourth aspect of the present application, the above-mentioned color toner contains a polyester resin, and the above-mentioned transparent toner contains a vinyl resin.

[0016] According to the fifth aspect of the present application, the above-mentioned transparent toner has at least two glass transition temperatures, and the difference between the lowest glass transition temperature and the highest glass transition temperature is 30 °C or more.

[0017] According to the sixth aspect of the present application, the above-mentioned transparent toner contains a styrene resin and a (meth)acrylate resin. The styrene resin contains styrene and other vinyl monomers in the polymerization components, and the (meth)acrylate resin contains at least two (meth)acrylates in the polymerization components, and the mass ratio of the (meth)acrylate in the overall polymerization components is 90% by mass or more.

[0018] According to the seventh aspect of the present application, the mass ratio of styrene in the overall polymerization components of the above-mentioned styrene resin is 60% by mass or more and 95% by mass or less.

[0019] According to the eighth aspect of the present application, the mass ratio of the two (meth)acrylates with the largest mass ratio among the above-mentioned at least two (meth)acrylates contained as polymerization components in the (meth)acrylate resin is 80:20 to 20:80.

[0020] According to the ninth aspect of the present application, the two (meth)acrylates with the largest mass ratio among the above-mentioned at least two (meth)acrylates contained as polymerization components in the (meth)acrylate resin are (meth)acrylate alkyl esters, and the difference in the number of carbon atoms of the alkyl groups of the two (meth)acrylate alkyl esters is 1 or more and 4 or less.

[0021] According to the tenth aspect of the present application, the above-mentioned other vinyl monomers contained as polymerization components in the above-mentioned styrene resin include (meth)acrylate.

[0022] According to the eleventh aspect of the present application, the above-mentioned other vinyl monomers contained as polymerization components in the above-mentioned styrene resin include at least one of n-butyl acrylate and 2-ethylhexyl acrylate.

[0023] According to the twelfth aspect of the present application, the above-mentioned styrene resin and the above-mentioned (meth)acrylate resin contain the same (meth)acrylate as polymerization components.

[0024] According to the thirteenth aspect of the present application, the above-mentioned (meth)acrylate resin contains 2-ethylhexyl acrylate and n-butyl acrylate as polymerization components.

[0025] According to the fourteenth aspect of the present application, the content of the above-mentioned styrene resin is more than the content of the above-mentioned (meth)acrylate resin.

[0026] According to the 15th aspect of the present application, it has a sea phase containing the above styrene resin and an island phase containing the above (meth)acrylate resin dispersed in the above sea phase.

[0027] According to the 16th aspect of the present application, the average diameter of the above island phase is 200 nm or more and 500 nm or less.

[0028] According to the 17th aspect of the present application, it has a core part containing the above styrene resin and the above (meth)acrylate resin and a shell layer covering the above core part.

[0029] According to the 18th aspect of the present application, the above shell layer contains the above styrene resin.

[0030] According to the 19th aspect of the present application, there is provided a developer set which has: a first electrophotographic developer containing the above color toner in the above toner set, and a second electrophotographic developer containing the above transparent toner in the above toner set.

[0031] According to the 20th aspect of the present application, there is provided a toner cartridge set which is installed in a printing material manufacturing apparatus and can be detached from the apparatus, and the toner cartridge set has: a first toner cartridge accommodating the above color toner in the above toner set and a second toner cartridge accommodating the above transparent toner in the above toner set.

[0032] According to the 21st aspect of the present application, there is provided a process cartridge set which is loaded and unloaded in a printing material manufacturing apparatus, and the process cartridge set has: a first process cartridge having a first developing unit which accommodates a first electrophotographic developer containing the above color toner in the above toner set and develops a color toner image formed on the surface of a photoreceptor into a color toner image by the above first electrophotographic developer; and a second process cartridge having a second developing unit which accommodates a second electrophotographic developer containing the above transparent toner in the above toner set and develops a transparent toner layer formed on the surface of a photoreceptor into a transparent toner layer by the above second electrophotographic developer.

[0033] According to the 22nd aspect of the present application, there is provided a printing material manufacturing apparatus, which includes: a color toner image forming unit that accommodates a first electrostatic image developer containing the color toner in the above toner group, and forms a color toner image on a recording medium by electrophotography using the first electrostatic image developer; a disposing unit that accommodates a second electrostatic image developer containing the transparent toner in the above toner group, and disposes the transparent toner on the recording medium by electrophotography to form a transparent toner layer; a heat fixing unit that includes a fixing member, and heat-fixes the color toner image on the recording medium in a state where the fixing member is in contact with the transparent toner layer; and a pressing unit that fold-presses the recording medium on which the color toner image is heat-fixed or overlaps and presses the recording medium on which the color toner image is heat-fixed with another recording medium.

[0034] According to the 23rd aspect of the present application, there is provided a printing material manufacturing method, which includes: a color toner image forming step of forming a color toner image on a recording medium by electrophotography using a first electrostatic image developer containing the color toner in the above toner group; a disposing step of disposing the transparent toner in the above toner group on the recording medium by electrophotography to form a transparent toner layer; a heat fixing step of heat-fixing the color toner image on the recording medium in a state where a fixing member is in contact with the transparent toner layer; and a pressing step of fold-pressing the recording medium on which the color toner image is heat-fixed or overlapping and pressing the recording medium on which the color toner image is heat-fixed with another recording medium.

[0035] Advantages of the Invention

[0036] According to the 1st or 4th aspect described above, there is provided a toner group that balances the suppression of offset during heat fixing and pressability as compared with the case where the above tanδ1 is less than 1.0 or greater than 4.0, or the above tanδ1 / tanδ2 is less than 1.2 or greater than 3.0.

[0037] According to the 2nd aspect described above, there is provided a toner group that balances the suppression of offset during heat fixing and pressability as compared with the case where the above tanδ1 is less than 1.5 or greater than 3.5.

[0038] According to the 3rd aspect described above, there is provided a toner group that balances the suppression of offset during heat fixing and pressability as compared with the case where the above tanδ1 / tanδ2 is less than 1.5 or greater than 2.9.

[0039] According to the fifth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure as compared with the following cases: a case where the glass transition temperature of the transparent toner is only one, or a case where there are at least two glass transition temperatures and the difference between the lowest glass transition temperature and the highest glass transition temperature is less than 30°C.

[0040] According to the sixth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure and has excellent adhesiveness as compared with a case where the (meth)acrylate resin is a homopolymer of (meth)acrylate.

[0041] According to the seventh aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure as compared with a case where the mass ratio of styrene in the total polymerization components of the styrene resin is greater than 95% by mass.

[0042] According to the eighth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure and has excellent adhesiveness as compared with a case where the mass ratio of the two (meth)acrylates having the largest mass ratio among at least two (meth)acrylates contained as polymerization components in the (meth)acrylate resin is outside the range of 80:20 to 20:80.

[0043] According to the ninth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure and has excellent adhesiveness as compared with a case where the difference in the number of carbon atoms of the alkyl groups of the two (meth)acrylic acid alkyl esters is 5 or more.

[0044] According to the tenth, eleventh, or twelfth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure as compared with a case where the transparent toner contains polystyrene instead of the styrene resin.

[0045] According to the thirteenth aspect described above, there is provided a toner group including a transparent toner that has excellent adhesiveness as compared with a case where the transparent toner contains a styrene resin and a (meth)acrylate resin and the (meth)acrylate resin is a homopolymer of 2-ethylhexyl acrylate.

[0046] According to the fourteenth aspect described above, there is provided a toner group including a transparent toner that maintains adhesiveness as compared with a case where the content of the styrene resin is less than the content of the (meth)acrylate resin.

[0047] According to the fifteenth aspect described above, there is provided a toner group including a transparent toner that is more likely to undergo a phase transition due to pressure and has excellent adhesiveness as compared with a case where the transparent toner does not have the above-mentioned sea-island structure.

[0048] According to the 16th aspect described above, there is provided a toner set including a transparent toner that is more likely to undergo a phase transition due to pressure than in the case where the average diameter of the island phase is greater than 500 nm.

[0049] According to the 17th aspect described above, there is provided a toner set including a transparent toner that is more likely to undergo a phase transition due to pressure than in the case where the transparent toner has a core-shell structure in which the core contains only a styrene resin or only a (meth)acrylate resin.

[0050] According to the 18th aspect described above, there is provided a toner set including a transparent toner that is more likely to undergo a phase transition due to pressure than in the case where the shell layer of the transparent toner does not contain a styrene resin but contains other resins.

[0051] According to the 19th aspect described above, there is provided a developer set that suppresses offset during heat fixing and has good crimpability compared to the case where tanδ1 is less than 1.0 or greater than 4.0, or where tanδ1 / tanδ2 is less than 1.2 or greater than 3.0.

[0052] According to the 20th aspect described above, there is provided a toner cartridge that separately accommodates each toner included in a toner set that suppresses offset during heat fixing and has good crimpability compared to the case where tanδ1 is less than 1.0 or greater than 4.0, or where tanδ1 / tanδ2 is less than 1.2 or greater than 3.0.

[0053] According to the 21st aspect described above, there is provided a set of processing cartridges for an electrostatic image developer that separately accommodates each toner included in a toner set that suppresses offset during heat fixing and has good crimpability compared to the case where tanδ1 is less than 1.0 or greater than 4.0, or where tanδ1 / tanδ2 is less than 1.2 or greater than 3.0.

[0054] According to the 22nd aspect described above, there is provided a printing apparatus that applies a toner set that suppresses offset during heat fixing and has good crimpability compared to the case where tanδ1 is less than 1.0 or greater than 4.0, or where tanδ1 / tanδ2 is less than 1.2 or greater than 3.0.

[0055] According to the 23rd aspect described above, there is provided a method for manufacturing a printed matter that applies a toner set that suppresses offset during heat fixing and has good crimpability compared to the case where tanδ1 is less than 1.0 or greater than 4.0, or where tanδ1 / tanδ2 is less than 1.2 or greater than 3.0. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 FIG. is a schematic view showing a part including a configuration unit and a crimping unit in an example of the printing apparatus of the present embodiment.

[0057] Figure 2 It is a schematic diagram showing another example of a printing material manufacturing apparatus according to the present embodiment.

[0058] Figure 3 It is a schematic diagram showing an example of a first processing cartridge constituting a processing cartridge group according to the present embodiment. Detailed Embodiments

[0059] Hereinafter, embodiments of the present application will be described. These descriptions and examples are for illustrating the embodiments and do not limit the scope of the embodiments.

[0060] In the present application, a numerical range represented by "~" means a range including the values described before and after "~" as the minimum value and the maximum value, respectively.

[0061] In the numerical ranges described stepwise in the present application, the upper limit value or the lower limit value described in one numerical range can be replaced with the upper limit value or the lower limit value of other stepwise described numerical ranges. Additionally, in the numerical ranges described in the present application, the upper limit value or the lower limit value of the numerical range can be replaced with the value shown in the examples.

[0062] In the present application, the term "process" includes not only independent processes but also includes cases where it cannot be clearly distinguished from other processes as long as the purpose of the process can be achieved.

[0063] When the embodiments are described with reference to the drawings in the present application, the configuration of the embodiments is not limited to the configuration shown in the drawings. Additionally, the dimensions of the components in each drawing are schematic dimensions, and the relative size relationships between the components are not limited thereto.

[0064] In the present application, each component may contain two or more conforming substances. When referring to the amount of each component in the composition, in the case where there are two or more conforming substances of each component in the composition, unless otherwise specified, it refers to the total amount of the two or more substances present in the composition.

[0065] In the present application, the particles conforming to each component may contain two or more. In the case where there are two or more particles conforming to each component in the composition, unless otherwise specified, the particle size of each component refers to the value for the mixture of the two or more particles present in the composition.

[0066] In the present application, an expression such as "(meth)acrylic acid" means that it can be either "acrylic acid" or "methacrylic acid".

[0067] In the present application, the color toner and the transparent toner are sometimes collectively referred to as "toner", and sometimes the "electrostatic image developer" is also simply referred to as "developer".

[0068] In the present application, a printed matter formed by folding a recording medium and bonding opposing surfaces to each other, or a printed matter formed by overlapping two or more recording media and bonding opposing surfaces to each other is referred to as a "pressure-bonded printed matter".

[0069] [Toner set]

[0070] The toner set of the present embodiment includes a color toner and a transparent toner having pressure transferability. When the tanδ at 100°C of the above-described color toner is tanδ1 and the tanδ at 100°C of the above-described transparent toner is tanδ2, the above-described tanδ1 is 1.0 or more and 4.0 or less, and the above-described tanδ1 and the above-described tanδ2 satisfy the following formula 1.

[0071] Formula 1: 1.2 ≤ tanδ1 / tanδ2 ≤ 3.0

[0072] Herein, the tanδ at 100°C of the toner is obtained as described below.

[0073] Specifically, it is obtained from the dynamic viscoelasticity measured by the sine wave vibration method. The dynamic viscoelasticity is measured using an ARES measuring device manufactured by Rheometric Scientific. The dynamic viscoelasticity is measured as follows: After forming the toner into a tablet, it is set on a parallel plate with a diameter of 8 mm, and after setting the normal force to 0, a sine wave vibration is applied at a vibration frequency of 6.28 rad / sec. The measurement starts at 20°C and continues to 120°C at a temperature increase rate of 1°C / minute. The measurement time interval at this time is 30 seconds.

[0074] In addition, the "color toner" refers to a toner in which the coloring agent amount in the toner particles exceeds 1.0 mass% with respect to the entire toner particles. In addition, the "transparent toner" refers to a toner in which the toner particles do not contain a coloring agent or the coloring agent amount in the toner particles is 1.0 mass% or less with respect to the entire toner particles.

[0075] The "toner having pressure transferability" refers to a toner that satisfies the following formula 3.

[0076] Formula 3 ··· 10°C ≤ T1 - T2

[0077] In formula 3, T1 is the temperature at which a viscosity of 10000 Pa·s is exhibited at a pressure of 1 MPa, and T2 is the temperature at which a viscosity of 10000 Pa·s is exhibited at a pressure of 10 MPa. The method for obtaining T1 and T2 is described later.

[0078] A printed matter is manufactured using a toner set including a colored toner and a pressure-transferable transparent toner. For example, after forming a transparent toner layer on a recording medium on which a colored toner image has been formed, a heat fixing process and a pressing process are performed.

[0079] In the above heat fixing process, for example, by heating the recording medium and the like while the fixing member is in contact with the transparent toner layer, the colored toner image is heat-fixed to the recording medium, and the transparent toner layer is fixed. In this heat fixing process, an offset phenomenon may occur in which at least a part of the transparent toner layer in contact with the fixing member (in some cases, at least a part of the transparent toner layer and the colored toner image) moves toward the fixing member side.

[0080] In contrast, in the toner set of the present embodiment, by making tanδ1 within the above range and making tanδ1 and tanδ2 satisfy the above formula 1, both the suppression of offset during heat fixing and the pressability are achieved. The reason is not yet certain, but it is speculated as follows.

[0081] First, by making tanδ1 within the above range, good fixability of the colored toner image to the recording medium is easily obtained. Specifically, when tanδ1 is within the above range, compared with the case where it is less than the above range, the colored toner image is more easily melted during heat fixing, has good heat fixability to the recording medium, and offset is also suppressed. In addition, when tanδ1 is within the above range, compared with the case where it is greater than the above range, the viscosity of the colored toner image does not become too high, offset is suppressed, and the pressability is also good.

[0082] Moreover, by making tanδ1 within the above range and making the value of tanδ1 / tanδ2 within the above range, both the suppression of offset during heat fixing and the pressability are achieved. Specifically, when the value of tanδ1 / tanδ2 is within the above range, compared with the case where it is less than the above range, the viscosity of the colored toner is relatively higher than that of the transparent toner layer, so the transparent toner layer is more likely to remain on the colored toner image side, and it is easier to suppress the movement of the transparent toner layer toward the fixing member side (i.e., offset). In addition, when the value of tanδ1 / tanδ2 is within the above range, compared with the case where it is greater than the above range, a decrease in pressability caused by an excessive increase in the viscosity of the transparent toner layer is suppressed.

[0083] Presumably for the above reasons, the toner set of the present embodiment achieves both the suppression of offset during heat fixing and the pressability.

[0084] The method of controlling tanδ1 and tanδ2 to satisfy the above conditions is not particularly limited, and examples include a method of adjusting the molecular weight of the toner particles contained in each toner and a method of adjusting the composition of the toner particles (such as the ratio of crystalline resin, etc.).

[0085] The toner group has at least a color toner and a pressure-transferable transparent toner, and may also have other toners as needed (for example, a transparent toner without pressure-transferability). Hereinafter, the pressure-transferable transparent toner may sometimes be simply referred to as the "transparent toner".

[0086] The color toner and the transparent toner may each be only one kind, or may be a combination of two or more kinds respectively.

[0087] Hereinafter, each toner constituting the toner group of the present embodiment will be described.

[0088] <Transparent toner>

[0089] As described above, the transparent toner has pressure-transferability.

[0090] The pressure-transferable transparent toner is not particularly limited as long as the relationship between tanδ2 and tanδ1 satisfies the above formula 1 and the above formula 3.

[0091] The pressure-transferable transparent toner preferably contains a vinyl-based resin. Here, the vinyl-based resin refers to a resin obtained by radical polymerization of a monomer having a vinyl group. As the monomer having a vinyl group, monomers having a vinyl group, (meth)acryloyl group, vinyl ether group, vinyl ester group, allyl group, etc. can be cited.

[0092] As a specific example of the pressure-transferable transparent toner, for example, a toner having at least two glass transition temperatures and the difference between the lowest glass transition temperature and the highest glass transition temperature being 30°C or more can be cited.

[0093] In addition, as a preferred example of a toner having a difference between the lowest glass transition temperature and the highest glass transition temperature of 30°C or more, for example, a toner in which the binder resin contains a styrene-based resin containing styrene and other vinyl monomers in the polymer component and a (meth)acrylate-based resin containing at least two (meth)acrylates and the mass ratio of the (meth)acrylate in the entire polymer component being 90% by mass or more can be cited.

[0094] In the following description, unless otherwise specified, the "styrene-based resin" refers to a "styrene-based resin containing styrene and other vinyl monomers in the polymer component", and the "(meth)acrylate-based resin" refers to a "(meth)acrylate-based resin containing at least two (meth)acrylates and the mass ratio of the (meth)acrylate in the entire polymer component being 90% by mass or more".

[0095] The toner in which the binder resin contains a styrene resin and a (meth)acrylate resin is more likely to undergo a phase transition due to pressure and has excellent adhesiveness compared to a toner containing a homopolymer of (meth)acrylate instead of the above (meth)acrylate resin. As its mechanism, the following is speculated.

[0096] Generally, the compatibility between a styrene resin and a (meth)acrylate resin with each other is low. Therefore, it is considered that the two resins are contained in the toner particles in a phase-separated state. It is also considered that when the toner particles are pressurized, the (meth)acrylate resin with a lower glass transition temperature first flows, and its flow spreads to the styrene resin, causing both resins to flow. It is further considered that after the two resins in the toner particles flow due to pressurization and then solidify to form a resin layer as the pressure is reduced, due to the low compatibility, a phase-separated state is formed again.

[0097] Since the (meth)acrylate resin containing at least two (meth)acrylates in the polymer component has at least two types of ester groups bonded to the main chain, the degree of molecular alignment in the solid state is lower than that of the homopolymer of (meth)acrylate. Therefore, it is speculated that it is more likely to flow due to pressurization. In addition, when the mass ratio of (meth)acrylate in the entire polymer component is 90% by mass or more, there are at least two types of ester groups and they are present in a high density. Therefore, the degree of molecular alignment in the solid state is even lower, and it is speculated that it is more likely to flow due to pressurization. Therefore, it is speculated that compared with a toner in which the (meth)acrylate resin is a homopolymer of (meth)acrylate, the above toner is more likely to flow due to pressure, that is, more likely to undergo a phase transition due to pressure.

[0098] Moreover, when the (meth)acrylate resin containing at least two (meth)acrylates and having a mass ratio of (meth)acrylate in the entire polymer component of 90% by mass or more is solidified again, the degree of molecular alignment is also low. Therefore, it is speculated that the phase separation from the styrene resin is a fine phase separation. It is speculated that the finer the state of phase separation between the styrene resin and the (meth)acrylate resin, the higher the uniformity of the state of the bonding surface with respect to the adherend and the more excellent the adhesiveness. Therefore, it is speculated that compared with a toner in which the (meth)acrylate resin is a homopolymer of (meth)acrylate, the above toner has excellent adhesiveness.

[0099] Hereinafter, as a preferred example of a transparent toner, for a toner in which the binder resin contains the above styrene resin and the above (meth)acrylate resin, the composition, structure, and properties will be described in detail.

[0100] The transparent toner contains at least toner particles and, if necessary, external additives.

[0101] (Toner particles)

[0102] The toner particles contain at least a binder resin. The binder resin contains, for example, a styrene resin and a (meth)acrylate resin.

[0103] The toner particles may contain a colorant, an anti-sticking agent, and other additives.

[0104] From the viewpoint of maintaining adhesiveness, the content of the styrene resin contained in the binder resin is preferably more than the content of the (meth)acrylate resin. The content of the styrene resin is preferably 55% by mass or more and 80% by mass or less, more preferably 60% by mass or more and 75% by mass or less, and still more preferably 65% by mass or more and 70% by mass or less, relative to the total content of the styrene resin and the (meth)acrylate resin.

[0105] - Styrene resin -

[0106] The above-mentioned toner particles contain, for example, a styrene resin in which the polymerization components contain styrene and other vinyl monomers.

[0107] Regarding the mass ratio of styrene in the entire polymerization components of the styrene resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 60% by mass or more, more preferably 70% by mass or more, and still more preferably 75% by mass or more; from the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, it is preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 85% by mass or less.

[0108] Examples of other vinyl monomers other than styrene that constitute the styrene resin include styrene monomers other than styrene and acrylic monomers.

[0109] Examples of styrene monomers other than styrene include vinylnaphthalene; alkyl-substituted styrenes such as α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, etc.; aryl-substituted styrenes such as p-phenylstyrene; alkoxy-substituted styrenes such as p-methoxystyrene; halogen-substituted styrenes such as p-chlorostyrene, 3,4-dichlorostyrene, p-fluorostyrene, 2,5-difluorostyrene, etc.; nitro-substituted styrenes such as m-nitrostyrene, o-nitrostyrene, p-nitrostyrene, etc. The styrene monomers may be used alone or in combination of two or more.

[0110] As an acrylic monomer, it is preferably at least one acrylic monomer selected from the group consisting of (meth)acrylic acid and (meth)acrylate. As the (meth)acrylate, examples thereof include (meth)acrylic acid alkyl esters, (meth)acrylic acid carboxy-substituted alkyl esters, (meth)acrylic acid hydroxy-substituted alkyl esters, (meth)acrylic acid alkoxy-substituted alkyl esters, di(meth)acrylates, etc. The acrylic monomer can be used alone or in combination of two or more.

[0111] As the (meth)acrylic acid alkyl ester, examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, isobornyl (meth)acrylate, etc.

[0112] As the (meth)acrylic acid carboxy-substituted alkyl ester, an example thereof is 2-carboxyethyl (meth)acrylate.

[0113] As the (meth)acrylic acid hydroxy-substituted alkyl ester, examples thereof include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.

[0114] As the (meth)acrylic acid alkoxy-substituted alkyl ester, an example thereof is 2-methoxyethyl (meth)acrylate.

[0115] As the di(meth)acrylate, examples thereof include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, pentanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, decanediol di(meth)acrylate, etc.

[0116] As the (meth)acrylate, examples thereof further include 2-(diethylamino)ethyl (meth)acrylate, benzyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, etc.

[0117] As other vinyl monomers constituting the styrene resin, in addition to styrene monomers and acrylic monomers, for example, (meth)acrylonitrile; vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, and vinyl isopropenyl ketone; and olefins such as isoprene, butene, and butadiene can be cited.

[0118] From the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, the styrene-based resin preferably contains (meth)acrylate as a polymerization component, more preferably contains an alkyl (meth)acrylate, further preferably contains an alkyl (meth)acrylate having 2 to 10 carbon atoms in the alkyl group, still further preferably contains an alkyl (meth)acrylate having 4 to 8 carbon atoms in the alkyl group, and particularly preferably contains at least one of n-butyl acrylate and 2-ethylhexyl acrylate. From the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, the styrene-based resin and the (meth)acrylate-based resin preferably contain the same (meth)acrylate as a polymerization component.

[0119] Regarding the mass ratio of the (meth)acrylate in the total polymerization components of the styrene-based resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 40% by mass or less, more preferably 30% by mass or less, and still further preferably 25% by mass or less; from the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, it is preferably 5% by mass or more, more preferably 10% by mass or more, and still further preferably 15% by mass or more. As the (meth)acrylate here, an alkyl (meth)acrylate is preferred, more preferably an alkyl (meth)acrylate having 2 to 10 carbon atoms in the alkyl group, and still further preferably an alkyl (meth)acrylate having 4 to 8 carbon atoms in the alkyl group.

[0120] The styrene-based resin particularly preferably contains at least one of n-butyl acrylate and 2-ethylhexyl acrylate as a polymerization component. Regarding the total amount of n-butyl acrylate and 2-ethylhexyl acrylate in the total polymerization components of the styrene-based resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 40% by mass or less, more preferably 30% by mass or less, and still further preferably 25% by mass or less; from the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, it is preferably 5% by mass or more, more preferably 10% by mass or more, and still further preferably 15% by mass or more.

[0121] Regarding the weight average molecular weight of the styrene-based resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 3000 or more, more preferably 4000 or more, and still further preferably 5000 or more; from the viewpoint of forming a toner that easily undergoes a phase transition due to pressure, it is preferably 50000 or less, more preferably 45000 or less, and still further preferably 40000 or less.

[0122] In this application, the weight-average molecular weight of the resin is measured by gel permeation chromatography (GPC). The molecular weight measurement using GPC is carried out using an HLC-8120GPC manufactured by Tosoh as the GPC device, a TSKgel SuperHM-M (15 cm) manufactured by Tosoh as the chromatographic column, and tetrahydrofuran as the solvent. The weight-average molecular weight of the resin is calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

[0123] Regarding the glass transition temperature of the styrene resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 30 °C or higher, more preferably 40 °C or higher, and further preferably 50 °C or higher; from the viewpoint of forming a toner that is prone to phase transition due to pressure, it is preferably 110 °C or lower, more preferably 100 °C or lower, and further preferably 90 °C or lower.

[0124] In this application, the glass transition temperature of the resin is determined from the differential scanning calorimetry (DSC) curve obtained by differential scanning calorimetry (DSC). More specifically, it is determined according to the "extrapolated glass transition start temperature" described in the method for determining the glass transition temperature in JIS K7121:1987 "Method for Measuring the Transition Temperature of Plastics".

[0125] The glass transition temperature of the resin is controlled by the type and polymerization ratio of the polymer components. The glass transition temperature has the following tendency: the higher the density of soft units such as methylene, ethylene, and ethylene oxide groups contained in the main chain, the lower the glass transition temperature; the higher the density of rigid units such as aromatic rings and cyclohexane rings contained in the main chain, the higher the glass transition temperature. In addition, the glass transition temperature has a tendency that the higher the density of aliphatic groups in the side chain, the lower the glass transition temperature.

[0126] Regarding the mass ratio of the styrene resin in the whole toner particles in the transparent toner, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 55% by mass or more, more preferably 60% by mass or more, and further preferably 65% by mass or more; from the viewpoint of forming a toner that is prone to phase transition due to pressure, it is preferably 80% by mass or less, more preferably 75% by mass or less, and further preferably 70% by mass or less.

[0127] -(Meth)acrylate resin-

[0128] The above toner particles contain, for example, a (meth)acrylate resin in which at least two (meth)acrylates are included in the polymer components and the mass ratio of the (meth)acrylates in the whole polymer components is 90% by mass or more.

[0129] The mass ratio of the (meth)acrylate in the total polymerization components of the (meth)acrylate resin may be, for example, 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and still more preferably 100%.

[0130] Examples of the (meth)acrylate include alkyl (meth)acrylates, carboxy-substituted alkyl (meth)acrylates, hydroxy-substituted alkyl (meth)acrylates, alkoxy-substituted alkyl (meth)acrylates, di(meth)acrylates, etc.

[0131] Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, isobornyl (meth)acrylate, etc.

[0132] Examples of the carboxy-substituted alkyl (meth)acrylate include 2-carboxyethyl (meth)acrylate, etc.

[0133] Examples of the hydroxy-substituted alkyl (meth)acrylate include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.

[0134] Examples of the alkoxy-substituted alkyl (meth)acrylate include 2-methoxyethyl (meth)acrylate, etc.

[0135] Examples of the di(meth)acrylate include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, pentanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, decanediol di(meth)acrylate, etc.

[0136] Examples of the (meth)acrylate also include 2-(diethylamino)ethyl (meth)acrylate, benzyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, etc.

[0137] The (meth)acrylate may be used alone or in combination of two or more.

[0138] As a (meth)acrylate, from the viewpoint of forming a toner that is prone to phase transfer due to pressure and has excellent adhesiveness, (meth)acrylic acid alkyl esters are preferred, (meth)acrylic acid alkyl esters having 2 or more and 10 or less carbon atoms in the alkyl group are more preferred, (meth)acrylic acid alkyl esters having 4 or more and 8 or less carbon atoms in the alkyl group are further preferred, and n-butyl acrylate and 2-ethylhexyl acrylate are particularly preferred. From the viewpoint of forming a toner that is prone to phase transfer due to pressure, the styrene resin and the (meth)acrylate resin preferably contain the same kind of (meth)acrylate as a polymerization component.

[0139] From the viewpoint of forming a toner that is prone to phase transfer due to pressure and has excellent adhesiveness, the mass ratio of the (meth)acrylic acid alkyl ester in the total polymerization components of the (meth)acrylate resin is preferably 90% by mass or more, more preferably 95% by mass or more, further preferably 98% by mass or more, and further preferably 100%. As the (meth)acrylic acid alkyl ester here, (meth)acrylic acid alkyl esters having 2 or more and 10 or less carbon atoms in the alkyl group are preferred, and (meth)acrylic acid alkyl esters having 4 or more and 8 or less carbon atoms in the alkyl group are more preferred.

[0140] From the viewpoint of forming a toner that is prone to phase transfer due to pressure and has excellent adhesiveness, the mass ratio of the two (meth)acrylic esters with the largest mass ratio among at least two (meth)acrylic esters contained as polymerization components in the (meth)acrylate resin is preferably 80:20 to 20:80, more preferably 70:30 to 30:70, and further preferably 60:40 to 40:60.

[0141] Among at least two (meth)acrylic esters contained as polymerization components in the (meth)acrylate resin, the two with the largest mass ratio are preferably (meth)acrylic acid alkyl esters. As the (meth)acrylic acid alkyl ester here, (meth)acrylic acid alkyl esters having 2 or more and 10 or less carbon atoms in the alkyl group are preferred, and (meth)acrylic acid alkyl esters having 4 or more and 8 or less carbon atoms in the alkyl group are more preferred.

[0142] When the two (meth)acrylic esters with the largest mass ratio among at least two (meth)acrylic esters contained as polymerization components in the (meth)acrylate resin are (meth)acrylic acid alkyl esters, from the viewpoint of forming a toner that is prone to phase transfer due to pressure and has excellent adhesiveness, the difference in the number of carbon atoms in the alkyl groups of the two (meth)acrylic acid alkyl esters is preferably 1 or more and 4 or less, more preferably 2 or more and 4 or less, and further preferably 3 or 4.

[0143] From the viewpoint of forming a toner that is prone to phase transition due to pressure and has excellent adhesiveness, the (meth)acrylate resin preferably contains n-butyl acrylate and 2-ethylhexyl acrylate as polymerization components. Particularly preferably, the two (meth)acrylates with the largest mass ratio among the at least two (meth)acrylates contained as polymerization components in the (meth)acrylate resin are n-butyl acrylate and 2-ethylhexyl acrylate. The total amount of n-butyl acrylate and 2-ethylhexyl acrylate preferably accounts for 90% by mass or more, more preferably 95% by mass or more, further preferably 98% by mass or more, and still further preferably 100% by mass in the total polymerization components of the (meth)acrylate resin.

[0144] (Meth)acrylate resins may contain vinyl monomers other than (meth)acrylates in the polymerization components. Examples of vinyl monomers other than (meth)acrylates include, for example, (meth)acrylic acid; styrene; styrene-based monomers other than styrene; (meth)acrylonitrile; vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, and vinyl isopropenyl ketone; and olefins such as isoprene, butene, and butadiene. These vinyl monomers can be used alone or in combination of two or more.

[0145] When the (meth)acrylate resin contains vinyl monomers other than (meth)acrylates in the polymerization components, as the vinyl monomers other than (meth)acrylates, at least one of acrylic acid and methacrylic acid is preferred, and acrylic acid is more preferred.

[0146] Regarding the weight-average molecular weight of the (meth)acrylate resin, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 100,000 or more, more preferably 120,000 or more, and further preferably 150,000 or more; from the viewpoint of forming a toner that is prone to phase transition due to pressure, it is preferably 250,000 or less, more preferably 220,000 or less, and further preferably 200,000 or less.

[0147] Regarding the glass transition temperature of the (meth)acrylate resin, from the viewpoint of forming a toner that is prone to phase transition due to pressure, it is preferably 10°C or less, more preferably 0°C or less, and further preferably -10°C or less; from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably -90°C or more, more preferably -80°C or more, and further preferably -70°C or more.

[0148] Regarding the mass ratio of the (meth)acrylate resin in the entire toner particles, from the viewpoint of forming a toner that is prone to phase transition due to pressure, it is preferably 20% by mass or more, more preferably 25% by mass or more, and still more preferably 30% by mass or more; from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 45% by mass or less, more preferably 40% by mass or less, and still more preferably 35% by mass or less.

[0149] The total amount of the styrene resin and the (meth)acrylate resin contained in the toner particles is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, and still more preferably 100% with respect to the entire toner particles.

[0150] - Other Resins -

[0151] The toner particles can contain, for example, non-vinyl resins such as polystyrene: epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, modified rosin, etc. These resins can be used alone or in combination of two or more.

[0152] - Various Additives -

[0153] The toner particles can contain, as needed, colorants (such as pigments, dyes), anti-sticking agents (such as hydrocarbon waxes; natural waxes such as carnauba wax, rice bran wax, candelilla wax; synthetic or mineral / petroleum-based waxes such as montan wax; ester-based waxes such as fatty acid esters, montanic acid esters), charge control agents, etc.

[0154] However, the toner particles do not contain a colorant, or the amount of the colorant in the toner particles is 1.0% by mass or less with respect to the entire toner particles. From the viewpoint of improving the transparency of the toner, the less the amount of the colorant in the toner particles, the more preferable.

[0155] - Structure of Toner Particles -

[0156] The internal structure of the toner particles is preferably a sea-island structure. As the sea-island structure, a sea-island structure having: a sea phase containing a styrene resin and an island phase containing a (meth)acrylate resin dispersed in the sea phase is preferred. The specific form of the styrene resin contained in the sea phase is as described above. The specific form of the (meth)acrylate resin contained in the island phase is as described above. An island phase containing no (meth)acrylate resin can be dispersed in the sea phase.

[0157] When the toner particles have a sea-island structure, the average diameter of the island phase is preferably 200 nm or more and 500 nm or less. When the average diameter of the island phase is 500 nm or less, the toner particles are likely to undergo phase transition due to pressure. When the average diameter of the island phase is 200 nm or more, the mechanical strength required for the toner particles (for example, the strength that is not easily deformed when stirred in a developing device) is excellent. From these viewpoints, the average diameter of the island phase is more preferably 220 nm or more and 450 nm or less, and further preferably 250 nm or more and 400 nm or less.

[0158] As a method for controlling the average diameter of the island phase of the sea-island structure within the above range, for example, in the method for manufacturing toner particles described below, the amount of (meth)acrylate resin relative to the amount of styrene resin can be increased or decreased, and the time maintained at a high temperature in the step of fusing / coalescing the aggregated resin particles can be increased or decreased.

[0159] The confirmation of the sea-island structure and the measurement of the average diameter of the island phase are carried out by the following method.

[0160] The toner is embedded in an epoxy resin, and a section is made using a diamond knife or the like. The made section is stained with osmium tetroxide or ruthenium tetroxide in a dryer. The stained section is observed using a scanning electron microscope (SEM). The sea phase and the island phase of the sea-island structure are distinguished by the light and shade caused by the staining degree of the resin by osmium tetroxide or ruthenium tetroxide, and the presence or absence of the sea-island structure is confirmed using this. 100 island phases are randomly selected from the SEM image, the major axis of each island phase is measured, and the average value of the 100 major axes is used as the average diameter.

[0161] The toner particles can be single-layer structured toner particles or core-shell structured toner particles having a core and a shell covering the core. From the viewpoint of suppressing the flow of the toner in an unpressurized state, the toner particles are preferably core-shell structured.

[0162] When the toner particles have a core-shell structure, from the viewpoint of being likely to undergo phase transition due to pressure, it is preferred that the core contains a styrene resin and a (meth)acrylate resin. Further, from the viewpoint of suppressing the flow of the toner in an unpressurized state, it is preferred that the shell contains a styrene resin. The specific form of the styrene resin is as described above. The specific form of the (meth)acrylate resin is as described above.

[0163] In the case where the toner particles have a core-shell structure, it is preferable that the core portion has a sea phase containing a styrene resin and an island phase containing a (meth)acrylate resin dispersed in the sea phase. The average diameter of the island phase is preferably in the range as described above. It is further preferable that the shell layer contains a styrene resin on the basis that the core portion has the above-described constitution. In this case, the sea phase of the core portion and the shell layer form a continuous structure, and the toner particles are liable to undergo a phase transition due to pressure. The specific manner of the styrene resin contained in the sea phase of the core portion is as described above. The specific manner of the (meth)acrylate resin contained in the island phase of the core portion is as described above.

[0164] As the resin contained in the shell layer, non-vinyl resins such as polystyrene, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, and modified rosin can also be cited. These resins can be used alone or in combination of two or more.

[0165] Regarding the average thickness of the shell layer, from the viewpoint of suppressing deformation of the toner particles, it is preferably 120 nm or more, more preferably 130 nm or more, and further preferably 140 nm or more. From the viewpoint of the toner particles being liable to undergo a phase transition due to pressure, it is preferably 550 nm or less, more preferably 500 nm or less, and further preferably 400 nm or less.

[0166] The average thickness of the shell layer is measured by the following method.

[0167] The toner is embedded in an epoxy resin, and a section is made using a diamond knife or the like. The section thus made is stained with osmium tetroxide or ruthenium tetroxide in a dryer. The stained section is observed with a scanning electron microscope (SEM). Ten toner particle cross-sections are randomly selected from the SEM image, the thickness of the shell layer is measured at 20 locations for one toner particle, and the average value is calculated. The average value of the 10 toner particles is taken as the average thickness.

[0168] Regarding the volume average particle diameter (D50v) of the toner particles, from the viewpoint of easy handling of the toner particles, it is preferably 4 μm or more, more preferably 5 μm or more, and further preferably 6 μm or more; from the viewpoint of the entire toner particles being liable to undergo a phase transition due to pressure, it is preferably 12 μm or less, more preferably 10 μm or less, and further preferably 9 μm or less.

[0169] The volume average particle diameter (D50v) of the toner particles was measured using a Coulter Multisizer II (manufactured by Beckman Coulter, Inc.) and a pore with a pore diameter of 100 μm. In 2 mL of a 5 mass% aqueous solution of sodium alkylbenzenesulfonate, 0.5 mg or more and 50 mg or less of toner particles were added and dispersed, and then mixed with 100 mL or more and 150 mL or less of an electrolytic solution (ISOTON-II, manufactured by Beckman Coulter, Inc.), and dispersed for 1 minute using an ultrasonic disperser. The resulting dispersion was used as a sample. The particle diameters of 50,000 particles with a particle diameter of 2 μm or more and 60 μm or less in the sample were measured. The particle diameter at which the cumulative volume reached 50% in the particle size distribution based on volume starting from the smaller diameter side was defined as the volume average particle diameter (D50v).

[0170] Regarding the weight average molecular weight of the toner particles, from the viewpoint of suppressing the offset during heat fixing, it is preferably 10,000 or more, more preferably 20,000 or more, and further preferably 50,000 or more; from the viewpoint of balancing the suppression of the offset during heat fixing and the crimpability, it is preferably 250,000 or less, more preferably 200,000 or less, and further preferably 150,000 or less.

[0171] Regarding the number average molecular weight of the toner particles, from the viewpoint of suppressing the offset during heat fixing, it is preferably 5,000 or more, more preferably 8,000 or more, and further preferably 10,000 or more; from the viewpoint of balancing the suppression of the offset during heat fixing and the crimpability, it is preferably 50,000 or less, more preferably 40,000 or less, and further preferably 30,000 or less.

[0172] (External additive)

[0173] Examples of the external additive include inorganic particles. Examples of the inorganic particles include 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·SiO 2 , K 2 O·(TiO 2 )n, Al 2 O 3 ·2SiO 2 , CaCO 3 , MgCO3 , BaSO 4 , MgSO 4 etc.

[0174] The surface of the inorganic particles as an external additive may be subjected to a hydrophobization treatment. The hydrophobization treatment is carried out, for example, by impregnating the inorganic particles in a hydrophobization treatment agent or the like. The hydrophobization treatment agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents, etc. They may be used alone or in combination of two or more. The amount of the hydrophobization treatment agent is, for example, 1 part by mass or more and 10 parts by mass or less relative to 100 parts by mass of the inorganic particles.

[0175] As external additives, resin particles (resin particles such as polystyrene, polymethyl methacrylate, 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.

[0176] The addition amount of the external additive is preferably 0.01% by mass or more and 5% by mass or less, more preferably 0.01% by mass or more and 2.0% by mass or less, relative to the toner particles.

[0177] (Properties of the transparent toner)

[0178] - Pressure phase transferability -

[0179] The above-mentioned transparent toner is a toner that undergoes a phase transfer due to pressure and satisfies the following formula 3.

[0180] Formula 3 ··· 10°C ≤ T1 - T2

[0181] In Formula 3, T1 is the temperature at which a viscosity of 10000 Pa·s is exhibited under a pressure of 1 MPa, and T2 is the temperature at which a viscosity of 10000 Pa·s is exhibited under a pressure of 10 MPa.

[0182] Regarding the temperature difference (T1 - T2), from the viewpoint that the toner is easily phase-transferred due to pressure, it is 10°C or more, preferably 15°C or more, more preferably 20°C or more; from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 120°C or less, more preferably 100°C or less, and further preferably 80°C or less.

[0183] The value of the temperature T1 is preferably 140°C or less, more preferably 130°C or less, further preferably 120°C or less, and particularly preferably 115°C or less.

[0184] The value of the temperature T2 is preferably 40°C or more, more preferably 50°C or more, further preferably 60°C or more. The upper limit of the temperature T2 is preferably 85°C or less.

[0185] As an index indicating that the toner is liable to undergo a phase transition due to pressure, the temperature difference (T1 - T3) between the temperature T1 at which the viscosity is 10,000 Pa·s at a pressure of 1 MPa and the temperature T3 at which the viscosity is 10,000 Pa·s at a pressure of 4 MPa can be cited. The temperature difference (T1 - T3) is preferably 5°C or more. From the viewpoint that the transparent toner is liable to undergo a phase transition due to pressure, the temperature difference (T1 - T3) is preferably 5°C or more, more preferably 10°C or more.

[0186] The temperature difference (T1 - T3) is usually 25°C or less.

[0187] From the viewpoint that the temperature difference (T1 - T3) is 5°C or more, the temperature T3 at which the viscosity is 10,000 Pa·s at a pressure of 4 MPa is preferably 90°C or less, more preferably 85°C or less, and further preferably 80°C or less. The lower limit of the temperature T3 is preferably 60°C or more.

[0188] The methods for obtaining the temperature T1, the temperature T2, and the temperature T3 are as described below.

[0189] The toner is compressed to produce a pellet-like specimen. The pellet-like specimen is placed in a flow tester (manufactured by Shimadzu Corporation, CFT - 500), the applied pressure is fixed at 1 MPa, and the viscosity with respect to temperature at 1 MPa is measured. From the obtained viscosity graph, the temperature T1 at which the viscosity reaches 10 4 Pa·s at an applied pressure of 1 MPa is determined. The temperature T2 is determined in the same manner as the method for the temperature T1 except that the applied pressure of 1 MPa is changed to 10 MPa. The temperature T3 is determined in the same manner as the method for the temperature T1 except that the applied pressure of 1 MPa is changed to 4 MPa. The temperature difference (T1 - T2) is calculated from the temperature T1 and the temperature T2. The temperature difference (T1 - T3) is calculated from the temperature T1 and the temperature T3.

[0190] - Glass transition temperature -

[0191] As described above, as an example of a toner having pressure phase transferability, for example, a toner having at least two glass transition temperatures and the difference between the lowest glass transition temperature and the highest glass transition temperature being 30°C or more can be cited. Further, in the case where the toner having at least two glass transition temperatures is a toner containing a styrene-based resin and a (meth)acrylate-based resin, one of the glass transition temperatures is presumably the glass transition temperature of the styrene-based resin, and the other is presumably the glass transition temperature of the (meth)acrylate-based resin.

[0192] The above transparent toner may have three or more glass transition temperatures, but the number of glass transition temperatures is preferably two. As a mode in which the number of glass transition temperatures is two, it is a mode in which the resin contained in the toner is only a styrene resin and a (meth)acrylate resin; a mode in which the content of other resins that are not styrene resins and (meth)acrylate resins is small (for example, a mode in which the content of other resins is 5% by mass or less with respect to the entire toner).

[0193] When the toner has at least two glass transition temperatures and the difference between the lowest glass transition temperature and the highest glass transition temperature is 30°C or more, from the viewpoint that the toner is likely to undergo a phase transition due to pressure, the difference between the lowest glass transition temperature and the highest glass transition temperature is more preferably 40°C or more, further preferably 50°C or more, and further preferably 60°C or more. The upper limit of the difference between the lowest glass transition temperature and the highest glass transition temperature is, for example, 140°C or less, and may be 130°C or less, or may be 120°C or less.

[0194] Regarding the lowest glass transition temperature exhibited by the toner, from the viewpoint that the toner is likely to undergo a phase transition due to pressure, it is preferably 10°C or less, more preferably 0°C or less, and further preferably -10°C or less; from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably -90°C or more, more preferably -80°C or more, and further preferably -70°C or more.

[0195] Regarding the highest glass transition temperature exhibited by the toner, from the viewpoint of suppressing the flow of the toner in the unpressurized state, it is preferably 30°C or more, more preferably 40°C or more, and further preferably 50°C or more; from the viewpoint that the toner is likely to undergo a phase transition due to pressure, it is preferably 70°C or less, more preferably 65°C or less, and further preferably 60°C or less.

[0196] In the present application, the glass transition temperature of the toner is obtained as follows: A plate-shaped specimen is prepared by compressing the toner, and differential scanning calorimetry (DSC) is performed on the specimen, and it is obtained from the resulting differential scanning calorimetry curve (DSC curve). More specifically, it is obtained according to the "extrapolated glass transition start temperature" described in the method for obtaining the glass transition temperature in JIS K7121:1987 "Method for Measuring the Transition Temperature of Plastics".

[0197] (Method for manufacturing a transparent toner)

[0198] The above transparent toner is obtained by externally adding an external additive to the toner particles after manufacturing the toner particles.

[0199] The toner particles can be manufactured by either a dry process (such as a kneading and pulverizing process, etc.) or a wet process (such as a coagulation and unification process, a suspension polymerization process, a dissolution and suspension process, etc.). These manufacturing processes are not particularly limited, and well-known processes are adopted. Among them, the toner particles can be obtained by the coagulation and unification process.

[0200] In the case of manufacturing toner particles by the coagulation and unification process, for example, the toner particles are manufactured through the following processes.

[0201] A process of preparing a styrene resin particle dispersion liquid in which styrene resin particles containing a styrene resin are dispersed (styrene resin particle dispersion liquid preparation process);

[0202] A process of polymerizing a (meth)acrylate resin in the styrene resin particle dispersion liquid to form composite resin particles containing a styrene resin and a (meth)acrylate resin (composite resin particle formation process);

[0203] A process of coagulating the composite resin particles in a composite resin particle dispersion liquid in which the composite resin particles are dispersed to form coagulated particles (coagulated particle formation process); and

[0204] A process of heating the coagulated particle dispersion liquid in which the coagulated particles are dispersed to fuse / unify the coagulated particles to form toner particles (fusion / unification process).

[0205] Hereinafter, the detailed content of each process will be described.

[0206] In the following description, a method for obtaining toner particles without a colorant and an anti-blocking agent will be described. The colorant, anti-blocking agent, and other additives can be used as needed. When the toner particles contain a colorant and an anti-blocking agent, after mixing the composite resin particle dispersion liquid, the colorant particle dispersion liquid, and the anti-blocking agent particle dispersion liquid, the fusion / unification process is performed. The colorant particle dispersion liquid and the anti-blocking agent particle dispersion liquid are prepared, for example, by mixing the materials and then performing a dispersion treatment using a well-known disperser.

[0207] - Styrene resin particle dispersion liquid preparation process -

[0208] The styrene resin particle dispersion liquid is, for example, a dispersion liquid in which styrene resin particles are dispersed in a dispersion medium using a surfactant.

[0209] Examples of the dispersion medium include aqueous media such as water and alcohols. They can be used alone or in combination of two or more.

[0210] As the surfactant, anionic surfactants such as sulfate ester salts, sulfonate salts, phosphate esters, and soaps can be mentioned; cationic surfactants such as amine salts and quaternary ammonium salts; nonionic surfactants such as polyethylene glycol series, alkylphenol ethylene oxide adduct series, and polyol series, etc. The nonionic surfactant can be used in combination with an anionic surfactant or a cationic surfactant. Among them, an anionic surfactant is preferred. The surfactant can be used alone or two or more kinds can be used in combination.

[0211] As a method for dispersing styrene resin particles in a dispersion medium, for example, a method of mixing the styrene resin and the dispersion medium and stirring and dispersing them using a rotary shear homogenizer, a ball mill with a medium, a sand mill, a Dyno mill, etc. can be mentioned.

[0212] As another method for dispersing styrene resin particles in a dispersion medium, an emulsion polymerization method can be mentioned. Specifically, after mixing the polymerization components of the styrene resin with a chain transfer agent or a polymerization initiator, an aqueous medium containing a surfactant is further mixed, and stirred to prepare an emulsion, and the styrene resin is polymerized in the emulsion. At this time, dodecyl mercaptan is preferably used as the chain transfer agent.

[0213] The volume average particle diameter of the styrene resin particles dispersed in the styrene resin particle dispersion is preferably 100 nm or more and 250 nm or less, more preferably 120 nm or more and 220 nm or less. Further preferably 150 nm or more and 200 nm or less.

[0214] The volume average particle diameter of the resin particles contained in the resin particle dispersion is measured as follows: The particle diameter is measured using a laser diffraction particle size distribution measuring device (for example, LA-700 manufactured by Horiba, Ltd.), and the particle diameter at which the cumulative value reaches 50% in the particle size distribution based on volume starting from the small diameter side is taken as the volume average particle diameter (D50v).

[0215] The content of the styrene resin particles contained in the styrene resin particle dispersion is preferably 30% by mass or more and 60% by mass or less, more preferably 40% by mass or more and 50% by mass or less.

[0216] -Composite resin particle formation step-

[0217] Mix the styrene resin particle dispersion with the polymerization components of the (meth)acrylate resin, and polymerize the (meth)acrylate resin in the styrene resin particle dispersion to form composite resin particles containing the styrene resin and the (meth)acrylate resin.

[0218] The composite resin particles are preferably resin particles containing a styrene-based resin and a (meth)acrylate-based resin in a microphase-separated state. Such resin particles are produced, for example, by the following method.

[0219] In a dispersion of styrene-based resin particles, a polymerization component of a (meth)acrylate-based resin (a monomer group containing at least two (meth)acrylates) is added, and an aqueous medium is added as needed. Then, while slowly stirring the dispersion, the temperature of the dispersion is heated to a temperature above the glass transition temperature of the styrene-based resin (for example, a temperature 10°C to 30°C higher than the glass transition temperature of the styrene-based resin). Next, while maintaining the temperature, an aqueous medium containing a polymerization initiator is slowly added dropwise, and further, stirring is continued for a long time in the range of 1 hour or more and 15 hours or less. At this time, ammonium persulfate is preferably used as the polymerization initiator.

[0220] Although the detailed mechanism is not necessarily clear, it is presumed that in the case of using the above method, the monomers and the polymerization initiator are impregnated in the styrene-based resin particles, and the (meth)acrylate polymerizes inside the styrene-based resin particles. Presumably thereby, a (meth)acrylate-based resin is contained inside the styrene-based resin particles, and composite resin particles in a state where microphase separation of the styrene-based resin and the (meth)acrylate-based resin is formed inside the particles are obtained.

[0221] The volume average particle diameter of the composite resin particles dispersed in the composite resin particle dispersion is preferably 140 nm or more and 300 nm or less, more preferably 150 nm or more and 280 nm or less, and still more preferably 160 nm or more and 250 nm or less.

[0222] The content of the composite resin particles contained in the composite resin particle dispersion is preferably 20% by mass or more and 50% by mass or less, more preferably 30% by mass or more and 40% by mass or less.

[0223] -Agglomerate particle formation step-

[0224] In the composite resin particle dispersion, the composite resin particles are agglomerated to form agglomerate particles having a diameter close to the target toner particle diameter.

[0225] Specifically, for example, a flocculant is added to the composite resin particle dispersion, and the pH of the composite resin particle dispersion is adjusted to acidic (for example, pH 2 or more and 5 or less). After adding a dispersion stabilizer as needed, the dispersion is heated to a temperature close to the glass transition temperature of the styrene-based resin (specifically, for example, -30°C or more and -10°C or less than the glass transition temperature of the styrene-based resin), and the composite resin particles are agglomerated to form agglomerate particles.

[0226] In the step of forming aggregated particles, while stirring the composite resin particle dispersion using a rotary shear homogenizer, a flocculant may be added at room temperature (e.g., 25 °C), the pH of the composite resin particle dispersion may be adjusted to acidic (e.g., pH 2 or more and 5 or less), and after adding a dispersion stabilizer as needed, heating may be performed.

[0227] As the flocculant, for example, a surfactant having a polarity opposite to that of the surfactant contained in the composite resin particle dispersion, 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 surfactant used is reduced and the charging characteristics are improved.

[0228] An additive that forms a complex or a similar bond with the metal ion of the flocculant may be used as needed together with the flocculant. As the additive, a chelating agent is preferably used.

[0229] 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 can be cited.

[0230] 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, and gluconic acid; aminocarboxylic acids such as iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA) can be cited.

[0231] The addition amount of the chelating agent 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, relative to 100 parts by mass of the resin particles.

[0232] -Fusion / Union Step-

[0233] Next, the aggregated particle dispersion in which the aggregated particles are dispersed is heated to, for example, a temperature above the glass transition temperature of the styrene resin (e.g., a temperature 10 °C to 30 °C higher than the glass transition temperature of the styrene resin), so that the aggregated particles are fused / unionized to form toner particles.

[0234] The toner particles obtained through the above steps usually have a sea-island structure, and the sea-island structure has a sea phase containing a styrene resin and an island phase containing a (meth)acrylate resin dispersed in the sea phase. It is speculated that the styrene resin and the (meth)acrylate resin are in a microphase-separated state in the composite resin particles, and in the fusion / union step, the styrene resins aggregate with each other to form the sea phase, and the (meth)acrylate resins aggregate with each other to form the island phase.

[0235] The average diameter of the island phase of the island structure is controlled, for example, by increasing or decreasing the amount of the styrene resin particle dispersion or the amount of at least two (meth)acrylates used in the composite resin particle forming step, and by increasing or decreasing the time maintained at a high temperature in the fusion / union step, etc.

[0236] The toner particles of the core-shell structure are manufactured, for example, through the following steps.

[0237] After obtaining the aggregated particle dispersion liquid, the aggregated particle dispersion liquid is further mixed with the styrene resin particle dispersion liquid, and aggregation is carried out so that styrene resin particles are further attached to the surface of the aggregated particles to form second aggregated particles; and

[0238] The second aggregated particle dispersion liquid in which the second aggregated particles are dispersed is heated to fuse / union the second aggregated particles to form toner particles of the core-shell structure.

[0239] The toner particles of the core-shell structure obtained through the above steps have a shell layer containing a styrene resin. A resin particle dispersion liquid in which other types of resin particles are dispersed can also be used instead of the styrene resin particle dispersion liquid to form a shell layer containing other types of resin.

[0240] After the fusion / union step is completed, the toner particles formed in the solution are subjected to a known cleaning step, a solid-liquid separation step, and a drying step to obtain toner particles in a dry state. From the viewpoint of chargeability, the cleaning step can be carried out by sufficient replacement cleaning using ion-exchanged water. From the viewpoint of productivity, the solid-liquid separation step can be carried out by suction filtration, pressure filtration, etc. From the viewpoint of productivity, the drying step can be carried out by freeze drying, fluidized bed drying, flow drying, vibration type fluidized bed drying, etc.

[0241] In addition, the above-mentioned transparent toner is manufactured, for example, by adding an external additive to the obtained toner particles in a dry state and mixing them. The mixing can be carried out, for example, by a V-type mixer, a Henschel mixer, or a Loedige mixer, etc. In addition, a vibrating sieve, an air classifier, etc. can be used as needed to remove coarse particles of the toner.

[0242] <Color toner>

[0243] The color toner is not particularly limited as long as the amount of the coloring agent in the toner particles exceeds 1.0 mass% with respect to the whole toner particles.

[0244] The color toner is composed of toner particles and, if necessary, an external additive.

[0245] (Toner particles)

[0246] The toner particles are composed of, for example, a binder resin and, as required, a colorant, an anti-sticking agent, and other additives.

[0247] -Binder resin-

[0248] As the binder resin, for example, vinyl resins composed of homopolymers of monomers such as styrenes (e.g., styrene, p-chlorostyrene, α-methylstyrene, etc.), (meth)acrylates (e.g., 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 (e.g., acrylonitrile, methacrylonitrile, etc.), vinyl ethers (e.g., vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), olefins (e.g., ethylene, propylene, butadiene, etc.), or copolymers formed by combining two or more of these monomers can be cited.

[0249] As the binder resin, for example, non-vinyl resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, modified rosin, mixtures of these with the above vinyl resins, or graft polymers obtained by polymerizing vinyl monomers in the coexistence of such non-vinyl resins can also be cited.

[0250] These binder resins can be used alone or in combination of two or more.

[0251] As the binder resin, a polyester resin is preferred.

[0252] As the polyester resin, for example, known amorphous polyester resins can be cited. The polyester resin can also be used in combination with a crystalline polyester resin. However, the crystalline polyester resin is preferably used in a range of 2% by mass or more and 40% by mass or less (preferably 2% by mass or more and 35% by mass or less) based on the total amount of the binder resin.

[0253] It should be noted that the "crystallinity" of the resin means that in differential scanning calorimetry (DSC), there is no stepwise heat absorption change 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 / minute) is within 10 °C.

[0254] On the other hand, the "amorphousness" of the resin means that the half-width exceeds 10 °C, shows a stepwise heat absorption change, or no clear endothermic peak is found.

[0255] ·Amorphous polyester resin

[0256] As the amorphous polyester resin, for example, condensates of polycarboxylic acids and polyols can be cited. It should be noted that as the amorphous polyester resin, commercially available products or synthetic products can be used.

[0257] 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 (for example, having 1 to 5 carbon atoms) alkyl esters can be cited. Among them, as the polycarboxylic acid, aromatic dicarboxylic acids are preferably used, for example.

[0258] The polycarboxylic acid can be used in combination with a tricarboxylic acid or higher having a crosslinked structure or a branched structure together with the dicarboxylic acid. As the tricarboxylic acid or higher, for example, trimellitic acid, pyromellitic acid, their acid anhydrides, or their lower (for example, having 1 to 5 carbon atoms) alkyl esters, etc. can be cited.

[0259] The polycarboxylic acid can be used alone or in combination of two or more.

[0260] As the polyol, for example, aliphatic diols (such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butylene glycol, hexylene glycol, 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 them, as the polyol, aromatic diols and alicyclic diols are preferably used, for example, and aromatic diols are more preferably used.

[0261] As the polyol, a polyol having a crosslinked structure or a branched structure with three or more hydroxyl groups can be used in combination with the diol. As the polyol having three or more hydroxyl groups, for example, glycerol, trimethylolpropane, pentaerythritol can be cited.

[0262] The polyol can be used alone or in combination of two or more.

[0263] 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.

[0264] 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, and further preferably 10,000 or higher and 300,000 or lower.

[0265] The number-average molecular weight (Mn) of the amorphous polyester resin is preferably 2,000 or more and 100,000 or less, more preferably 3,000 or more and 20,000 or less.

[0266] 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.

[0267] The amorphous polyester resin can be obtained by a known production method. Specifically, for example, it is obtained by a method in which the polymerization temperature is 180°C or more and 230°C or less, the pressure in the reaction system is reduced as needed, and the reaction is carried out while removing water and alcohol generated during condensation.

[0268] It should be noted that when the raw material monomers are insoluble or immiscible at the reaction temperature, a high-boiling solvent can be added as a solubilizer to dissolve the monomers. In this case, the polycondensation reaction is carried out while distilling off the solubilizer. In the case where there are monomers with poor compatibility, the monomers with poor compatibility can be pre-condensed with an acid or alcohol that is pre-polycondensed with the monomers and then polycondensed together with the main components.

[0269] · Crystalline polyester resin

[0270] Examples of the crystalline polyester resin include condensates of polycarboxylic acids and polyols. It should be noted that as the crystalline polyester resin, commercially available products or synthetic products can be used.

[0271] Here, in order to easily form a crystal structure, compared with polymerizable monomers having an aromatic group, the crystalline polyester resin preferably uses a condensate of polymerizable monomers having a linear aliphatic group.

[0272] Examples of the polycarboxylic acid include 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, etc. dibasic acids), their acid anhydrides, or their lower (e.g., having 1 to 5 carbon atoms) alkyl esters.

[0273] The polycarboxylic acid can be used in combination with a carboxylic acid having a crosslinked structure or a branched structure together with the dicarboxylic acid. Examples of the tricarboxylic acid include 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 (e.g., having 1 to 5 carbon atoms) alkyl esters.

[0274] As a polycarboxylic acid, a dicarboxylic acid having a sulfonic acid group or a dicarboxylic acid having an ethylenic double bond can be used in combination with these dicarboxylic acids.

[0275] One kind of polycarboxylic acid can be used alone, or two or more kinds can be used in combination.

[0276] Examples of the polyol include aliphatic diols (e.g., linear aliphatic diols having 7 or more and 20 or less carbon atoms in the main chain). Examples of the aliphatic diol include 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. Among them, as the aliphatic diol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferred.

[0277] The polyol can be used in combination with a trihydric or higher alcohol having a crosslinked structure or a branched structure together with the diol. Examples of the trihydric or higher alcohol include glycerol, trimethylolethane, trimethylolpropane, pentaerythritol, etc.

[0278] One kind of polyol can be used alone, or two or more kinds can be used in combination.

[0279] Here, in the polyol, the content of the aliphatic diol can be set to 80 mol% or more, preferably 90 mol% or more.

[0280] 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.

[0281] It should be noted that the melting temperature is obtained as follows: from the DSC curve obtained by differential scanning calorimetry (DSC), the "melting peak temperature" described in the method for obtaining the melting temperature in JIS K7121-1987 "Method for Measuring the Transition Temperature of Plastics" is obtained.

[0282] The weight average molecular weight (Mw) of the crystalline polyester resin is preferably 6000 or more and 35000 or less.

[0283] The crystalline polyester resin is obtained, for example, by a known production method in the same manner as the amorphous polyester resin.

[0284] As the content of the binder resin, for example, relative to the entire toner particles, it 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.

[0285] -Colorant-

[0286] As the colorant, various pigments such as carbon black, chrome yellow, Hansa yellow, benzidine yellow, indanthrene yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, Vulcan orange, Lake Red (Watch Young Red), permanent red, brilliant carmine 3B, brilliant carmine 6B, DuPont oil red, pyrazolone red, Lithol red, rhodamine B lake, Lake Red C, pigment red, rose red, aniline blue, ultramarine blue, Calco oil blue, methylene blue chloride, phthalocyanine blue, pigment blue, phthalocyanine green, and malachite green oxalate can be cited; or various dyes such as acridine-based, xanthene-based, azo-based, benzoquinone-based, azine-based, anthraquinone-based, thioindigo-based, dioxazine-based, thiazine-based, azomethine-based, indigo-based, phthalocyanine-based, aniline black-based, polymethine-based, triphenylmethane-based, diphenylmethane-based, thiazole-based, etc.

[0287] The colorant can be used alone or in combination of two or more.

[0288] As the colorant, a colorant that has been surface-treated as needed can be used, or it can be used in combination with a dispersant. In addition, two or more colorants can be used in combination.

[0289] As the content of the colorant, for example, relative to the entire toner particles, it is preferably 1% by mass or more and 30% by mass or less, more preferably 3% by mass or more and 15% by mass or less.

[0290] -Anti-sticking agent-

[0291] As the anti-sticking agent, for example, hydrocarbon waxes; natural waxes such as carnauba wax, rice bran wax, and candelilla wax; synthetic or mineral / oil-based waxes such as montan wax; ester-based waxes such as fatty acid esters and montanic acid esters, etc. The anti-sticking agent is not limited thereto.

[0292] The melting temperature of the anti-sticking agent is preferably 50°C or more and 110°C or less, more preferably 60°C or more and 100°C or less.

[0293] It should be noted that the melting temperature is obtained as follows: from the DSC curve obtained by differential scanning calorimetry (DSC), the "melting peak temperature" described in the method for obtaining the melting temperature in JIS K 7121-1987 "Method for Measuring the Transition Temperature of Plastics" is obtained.

[0294] As the content of the anti-sticking agent, for example, relative to the entire toner particles, it 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.

[0295] -Other additives-

[0296] As other additives, known additives such as magnetic materials, charge control agents, inorganic powders, etc. can be cited. These additives are included in the toner particles as internal additives.

[0297] -Properties of toner particles, etc.-

[0298] The toner particles can be single-layer toner particles or so-called core-shell structured toner particles composed of a core part (core particles) and a coating layer (shell layer) covering the core part.

[0299] Here, the core-shell structured toner particles can be composed of, for example, a core part containing a binder resin and other additives such as a colorant and an anti-sticking agent as needed, and a coating layer containing a binder resin.

[0300] As the volume average particle diameter (D50v) of the toner particles, it is preferably 2 μm or more and 10 μm or less, more preferably 4 μm or more and 8 μm or less.

[0301] As the average roundness of the toner particles, it is preferably 0.94 or more and 1.00 or less, more preferably 0.95 or more and 0.98 or less.

[0302] The average roundness of the toner particles is obtained by (equivalent circular circumference) / (circumference) [(circumference of a circle having the same projected area as the particle image) / (circumference of the particle projected image)]. Specifically, it is the value measured by the following method.

[0303] First, the toner particles to be measured are attracted and collected to form a flat flow, and are instantaneously stroboscopically illuminated, thereby reading the particle image in the form of a still image, and obtained by a flow particle image analyzer (FPIA-3000 manufactured by Sysmex Corporation) that analyzes the particle image. In addition, the number of samples when calculating the average roundness is set to 3500.

[0304] It should be noted that when the toner has an external additive, the toner (developer) to be measured is dispersed in water containing a surfactant and then ultrasonicated to obtain toner particles from which the external additive has been removed.

[0305] (External additive)

[0306] As the external additive, for example, the same inorganic particles as those used as the external additive of the transparent toner can be cited.

[0307] As the external additive, 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.

[0308] The amount of the external additive added is, for example, preferably from 0.01% by mass to 5% by mass, and more preferably from 0.01% by mass to 2.0% by mass, based on the toner particles.

[0309] (Method for producing color toner)

[0310] Next, a method for producing color toner will be described.

[0311] Color toner is obtained by adding an external additive to toner particles after toner particles are manufactured.

[0312] The toner particles can be produced by any of dry methods (such as kneading and pulverization methods) and wet methods (such as aggregation, suspension polymerization, and dissolution suspension methods). The method for producing the toner particles is not particularly limited to these methods, and a known method can be used.

[0313] Among them, it is preferable to obtain toner particles by an aggregation method.

[0314] In addition, the color toner is produced, for example, by adding an external additive to the obtained dry toner particles and mixing them. The mixing can be performed by, for example, a V-type blender, a Henschel mixer, or a Loedige mixer. In addition, coarse particles of the toner can be removed using a vibration sieving machine, a wind sieving machine, or the like as needed.

[0315] <Toner Set Configuration>

[0316] The combination of the color toner and the transparent toner is not particularly limited as long as tan δ1 and tan δ2 satisfy the above conditions.

[0317] Tan δ1 is 1.0 to 4.0, and is preferably 1.5 to 3.5, and more preferably 2 to 3, from the viewpoint of fixability of the color toner image to the recording medium, color development of the color toner image, and suppression of offset.

[0318] From the viewpoint of achieving both suppression of offset during heat fixing and pressure-bonding properties, tan δ2 is preferably 0.5 to 2, more preferably 0.7 to 1.5, and even more preferably 0.8 to 1.3.

[0319] The value of tan δ1 / tan δ2 is 1.2 to 3.0, and is preferably 1.5 to 2.9, and more preferably 1.8 to 2.5, from the viewpoint of achieving both suppression of offset during heat fixing and pressure-bonding properties.

[0320] As a preferred combination of a color toner and a transparent toner, for example, a combination of a color toner containing a polyester resin and a transparent toner containing a vinyl resin can be cited.

[0321] [Developer set]

[0322] The developer set of the present embodiment includes: a first electrophotographic developer containing at least the color toner in the toner set of the present embodiment and a second electrophotographic developer containing at least the transparent toner in the toner set of the present embodiment. The electrophotographic developers constituting the developer set of the present embodiment may be single-component developers containing only the above-mentioned toner, or two-component developers obtained by mixing the above-mentioned toner and a carrier. It should be noted that when both the first electrophotographic developer and the second electrophotographic developer are two-component developers, the types and contents of the carriers contained in these developers may be the same or different from each other.

[0323] 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 composed 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 is impregnated into porous magnetic powder, etc. can be cited. The magnetic powder-dispersed carrier and the resin-impregnated carrier may be carriers in which the constituent particles of the carrier are used as the core material and the surface thereof is coated with resin.

[0324] As the magnetic powder, for example, magnetic metals such as iron, nickel, and cobalt; magnetic oxides such as ferrite and magnetite, etc. can be cited.

[0325] As the coating resin 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, linear silicone resin or its modified product composed of an organosiloxane bond, fluororesin, polyester, polycarbonate, phenolic resin, epoxy resin, etc. can be cited. Other additives such as conductive particles may be contained in the coating resin and the base resin. As the conductive particles, particles such as 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.

[0326] In order to coat the surface of the core material with resin, for example, a method of coating with a coating layer-forming solution obtained by dissolving the coating resin and various additives (used as needed) in an appropriate solvent can be cited. There is no particular limitation on the solvent, and it can be selected in consideration of the type of resin used, coating adaptability, etc.

[0327] As a specific resin coating method, an immersion method in which a core material is immersed in a coating layer forming solution; a spraying method in which a coating layer forming solution is sprayed onto the surface of the core material; a fluidized bed method in which a coating layer forming solution is sprayed in a state where the core material is floating by flowing air; a kneading coater method in which a core material of a carrier and a coating layer forming solution are mixed in a kneading coater and then the solvent is removed, and the like can be cited.

[0328] The mixing ratio (mass ratio) of the toner and the carrier in the two-component developer is preferably toner:carrier = 1:100 to 30:100, more preferably 3:100 to 20:100.

[0329] [Printing apparatus, method for manufacturing a printed matter]

[0330] The printing apparatus of the present embodiment includes: a color toner image forming unit that accommodates a first electrophotographic developer containing the color toner in the toner group of the present embodiment and forms a color toner image on a recording medium by an electrophotographic method using the first electrophotographic developer; a disposing unit that accommodates a second electrophotographic developer containing the transparent toner in the toner group of the present embodiment and disposes the transparent toner on the recording medium by an electrophotographic method to form a transparent toner layer; a heat fixing unit that includes a fixing member and heat-fixes the color toner image to the recording medium in a state where the fixing member is in contact with the transparent toner layer; and a crimping unit that crimps the recording medium on which the color toner image is heat-fixed by folding or crimps the recording medium on which the color toner image is heat-fixed and another recording medium by overlapping.

[0331] By the printing apparatus of the present embodiment, the method for manufacturing a printed matter of the present embodiment is implemented.

[0332] The method for manufacturing a printed matter of the present embodiment includes: a color toner image forming step of forming a color toner image on a recording medium by an electrophotographic method using a first electrophotographic developer containing the color toner in the toner group of the present embodiment; a disposing step of disposing the transparent toner on the recording medium by an electrophotographic method using a second electrophotographic developer containing the transparent toner in the toner group of the present embodiment to form a transparent toner layer; a heat fixing step of heat-fixing the color toner image to the recording medium in a state where the fixing member is in contact with the transparent toner layer; and a crimping step of crimping the recording medium on which the color toner image is heat-fixed by folding or crimping the recording medium on which the color toner image is heat-fixed and another recording medium by overlapping.

[0333] The color toner image forming unit included in the printing apparatus of the present embodiment includes, for example:

[0334] A photoreceptor;

[0335] A charging unit for charging the surface of the above-described photoreceptor;

[0336] An electrostatic image forming unit for forming an electrostatic image on the surface of the charged photoreceptor;

[0337] A developing unit that accommodates a first electrostatic image developer containing a color toner in the toner set of the present embodiment and develops the electrostatic image formed on the surface of the photoreceptor into a color toner image; and

[0338] A transfer unit that transfers the toner image formed on the surface of the photoreceptor to the surface of a recording medium.

[0339] The above-described configuration units included in the printing apparatus of the present embodiment, for example, include:

[0340] A photoreceptor;

[0341] A charging unit for charging the surface of the above-described photoreceptor;

[0342] An electrostatic image forming unit for forming an electrostatic image on the surface of the charged photoreceptor;

[0343] A developing unit that accommodates a second electrostatic image developer containing a transparent toner in the toner set of the present embodiment and develops the electrostatic image formed on the surface of the photoreceptor into a transparent toner layer; and

[0344] A transfer unit that transfers the transparent toner layer formed on the surface of the photoreceptor to the surface of a recording medium.

[0345] The color toner image forming step included in the method for manufacturing a printed matter of the present embodiment, for example, includes:

[0346] A charging step of charging the surface of a photoreceptor;

[0347] An electrostatic image forming step of forming an electrostatic image on the surface of the charged photoreceptor;

[0348] A developing step of developing the electrostatic image formed on the surface of the photoreceptor into a color toner image by a first electrostatic image developer containing a color toner in the toner set of the present embodiment; and

[0349] A transfer step of transferring the color toner image formed on the surface of the photoreceptor to the surface of a recording medium.

[0350] The above-described configuration steps included in the method for manufacturing a printed matter of the present embodiment, for example, include:

[0351] A charging step of charging the surface of the photoreceptor;

[0352] An electrostatic image forming step of forming an electrostatic image on the surface of the charged photoreceptor;

[0353] A developing step of developing the electrostatic image formed on the surface of the photoreceptor into a transparent toner layer by a second electrostatic image developer containing the transparent toner in the toner set of the present embodiment; and

[0354] A transfer step of transferring the transparent toner layer formed on the surface of the photoreceptor to the surface of the recording medium.

[0355] The above-described color toner image forming unit is, for example: a device of a direct transfer method that directly transfers the color toner image formed on the surface of the photoreceptor to the recording medium; a device of an intermediate transfer method that transfers the color toner image formed on the surface of the photoreceptor to the surface of an intermediate transfer body once and then transfers the color toner image transferred to the surface of the intermediate transfer body to the surface of the recording medium twice; a device having a cleaning unit that cleans the surface of the photoreceptor before charging after transferring the color toner image; a device having a charge removal unit that irradiates the surface of the photoreceptor with charge removal light for charge removal after transferring the color toner image and before charging, etc. In the case where the above-described color toner image forming unit is a device of an intermediate transfer method, the transfer unit has: for example, an intermediate transfer body to which the color toner image is transferred to the surface; a primary transfer unit that transfers the color toner image formed on the surface of the photoreceptor to the surface of the intermediate transfer body once; a secondary transfer unit that transfers the color toner image transferred to the surface of the intermediate transfer body to the surface of the recording medium twice.

[0356] The above-described configuration unit is, for example: a device of a direct transfer method that directly transfers the transparent toner layer formed on the surface of the photoreceptor to the recording medium on which the color toner image is formed; a device of an intermediate transfer method that transfers the transparent toner layer formed on the surface of the photoreceptor to the surface of an intermediate transfer body once and then transfers the transparent toner layer transferred to the surface of the intermediate transfer body to the surface of the recording medium twice; a device having a cleaning unit that cleans the surface of the photoreceptor before charging after transferring the transparent toner layer; a device having a charge removal unit that irradiates the surface of the photoreceptor with charge removal light for charge removal after transferring the transparent toner layer and before charging, etc. In the case where the above-described configuration unit is a device of an intermediate transfer method, the transfer unit has: for example, an intermediate transfer body to which the transparent toner layer is transferred to the surface; a primary transfer unit that transfers the transparent toner layer formed on the surface of the photoreceptor to the surface of the intermediate transfer body once; a secondary transfer unit that transfers the transparent toner layer transferred to the surface of the intermediate transfer body to the surface of the recording medium twice.

[0357] In the above-described color toner image forming unit and the configuration unit, the part containing the developing unit in each may be a cartridge structure (so-called processing cartridge) that can be loaded and unloaded in the above-described color toner image forming unit and the configuration unit. As the processing cartridge, for example, a processing cartridge having a developing unit that accommodates each electrostatic image developer in the developer group of the present embodiment is preferably used. The processing cartridge may constitute a processing cartridge group having a first processing cartridge and a second processing cartridge. The first processing cartridge has a first developing unit that accommodates a first electrostatic image developer, and the second processing cartridge has a second developing unit that accommodates a second electrostatic image developer.

[0358] The crimping unit included in the printing apparatus of the present embodiment applies pressure to a recording medium on which the transparent toner in the toner group of the present embodiment is disposed. As a result, the transparent toner flows on the recording medium and exhibits adhesiveness. For the purpose of causing the transparent toner to flow, the pressure applied by the crimping unit to the recording medium is preferably 3 MPa or more and 300 MPa or less, more preferably 10 MPa or more and 200 MPa or less, and further preferably 30 MPa or more and 150 MPa or less.

[0359] The transparent toner in the toner group of the present embodiment may be disposed over the entire surface of the recording medium or may be disposed on a part of the recording medium. The transparent toner in the toner group of the present embodiment is disposed in one layer or two or more layers on the recording medium. The layer of the transparent toner in the present embodiment may be a continuous layer in the plane direction of the recording medium or may be a discontinuous layer in the plane direction of the recording medium.

[0360] The amount of the transparent toner on the recording medium is, for example, 0.5 g / m 2 to 50 g / m 2 or less, 1 g / m 2 to 40 g / m 2 or less, 1.5 g / m 2 to 30 g / m 2 or less. The layer thickness of the transparent toner on the recording medium is, for example, 0.2 μm or more and 25 μm or less, 0.4 μm or more and 20 μm or less, 0.6 μm or more and 15 μm or less.

[0361] Examples of the recording medium used in the printing apparatus of the present embodiment include paper, coated paper, such as art paper, cloth, non-woven fabric, resin film, resin sheet, etc. The recording medium may have an image on one side or both sides.

[0362] Hereinafter, an example of the printing apparatus of the present embodiment is shown, but the present embodiment is not limited thereto.

[0363] Figure 1 It is a schematic configuration diagram showing a part including a configuration unit and a crimping unit in an example of a printing material manufacturing apparatus according to the present embodiment. Figure 1 The shown printing material manufacturing apparatus includes a configuration unit 100 and a crimping unit 200 disposed downstream of the configuration unit 100. The arrow indicates the rotation direction of the photoreceptor or the conveyance direction of the recording medium.

[0364] The configuration unit 100 is a direct transfer type apparatus that uses a developer containing a transparent toner in the toner set of the present embodiment and disposes the transparent toner on a recording medium P on which a color toner image is formed by an electrophotographic method. The recording medium P has a color toner image pre-formed on one or both sides.

[0365] The configuration unit 100 has a photoreceptor 101. Around the photoreceptor 101, there are sequentially disposed: a charging roller (an example of a charging unit) 102 that charges the surface of the photoreceptor 101, an exposure device (an example of an electrostatic image forming unit) 103 that exposes the charged surface of the photoreceptor 101 with a laser beam to form an electrostatic image, a developing device (an example of a developing unit) 104 that supplies toner to the electrostatic image and develops the electrostatic image, a transfer roller (an example of a transfer unit) 105 that transfers the developed toner image onto the recording medium P, and a photoreceptor cleaning device (an example of a cleaning unit) 106 that removes the toner remaining on the surface of the photoreceptor 101 after transfer.

[0366] The operation of the configuration unit 100 for disposing the transparent toner on the recording medium P will be described.

[0367] First, the surface of the photoreceptor 101 is charged by the charging roller 102. According to image data sent from a control unit (not shown), the exposure device 103 irradiates the charged surface of the photoreceptor 101 with a laser beam. Thereby, an electrostatic image of the arrangement pattern of the transparent toner is formed on the surface of the photoreceptor 101.

[0368] The electrostatic image formed on the photoreceptor 101 rotates to the developing position as the photoreceptor 101 rotates. And, at the developing position, the electrostatic image on the photoreceptor 101 is developed by the developing device 104 to form a transparent toner layer.

[0369] Inside the developing device 104, a developer containing at least a transparent toner and a carrier is accommodated. The transparent toner and the carrier are agitated together inside the developing device 104, thereby triboelectrically charging and being held on the developing roller. The surface of the photoreceptor 101 passes through the developing device 104, so that the transparent toner electrostatically adheres to the electrostatic image on the surface of the photoreceptor 101, and the electrostatic image is developed by the transparent toner. The photoreceptor 101 formed with a transparent toner layer of the transparent toner continues to rotate, and the transparent toner layer developed on the photoreceptor 101 is conveyed to the transfer position.

[0370] When the transparent toner layer on the photoreceptor 101 is conveyed to the transfer position, a transfer bias is applied to the transfer roller 105, and an electrostatic force from the photoreceptor 101 toward the transfer roller 105 acts on the transparent toner layer, so that the transparent toner layer on the photoreceptor 101 is transferred onto the recording medium P.

[0371] The transparent toner remaining on the photoreceptor 101 is removed and recovered in the photoreceptor cleaning device 106. The photoreceptor cleaning device 106 is, for example, a cleaning blade, a cleaning brush, etc. From the viewpoint of suppressing the phenomenon that the transparent toner remaining on the surface of the photoreceptor flows due to pressure and adheres to the surface of the photoreceptor in a film shape, the photoreceptor cleaning device 106 is preferably a cleaning brush.

[0372] The recording medium P transferred with the transparent toner layer is conveyed to a fixing device (an example of a fixing unit) 107. The fixing device 107 is, for example, a pair of fixing members (roller / roller, belt / roller). The pressure applied by the fixing device 107 to the recording medium P can be lower than the pressure applied by the pressing device 230 to the recording medium P. Specifically, it is preferably 0.2 MPa or more and 1 MPa or less.

[0373] The fixing device 107 may or may not have a heating source (such as a halogen heater) for heating the recording medium P inside. When the fixing device 107 has a heating source inside, the surface temperature of the recording medium P heated by the heating source is preferably 150 °C or more and 220 °C or less, more preferably 155 °C or more and 210 °C or less, and further preferably 160 °C or more and 200 °C or less. It should be noted that the fixing device 107 not having a heating source inside does not exclude the temperature inside the fixing device 107 reaching above the ambient temperature due to the heat generated by a motor or the like provided in the configuration unit 100.

[0374] The recording medium P passes through the configuration unit 100, thereby forming a recording medium P1 with a transparent toner applied to the image. The recording medium P1 is conveyed to the crimping unit 200.

[0375] In the manufacturing apparatus of the printed matter according to the present embodiment, the arranging unit 100 and the crimping unit 200 may be arranged in a close manner or in a separated manner. When the arranging unit 100 and the crimping unit 200 are separated, the arranging unit 100 and the crimping unit 200 are connected, for example, by a conveying unit (such as a belt conveyor) that conveys the recording medium P1.

[0376] The crimping unit 200 includes a folding device 220 and a pressing device 230, and is a unit that folds and crimps the recording medium P1.

[0377] The folding device 220 folds the recording medium P1 passing through the device to produce a folded recording medium P2. The folding method of the recording medium P2 is, for example, folding in half, folding into three, or folding into four, and may be a method in which only a part of the recording medium P2 is folded. The recording medium P2 is in a state where a transparent toner is arranged on at least a part of at least one of two opposing surfaces.

[0378] The folding device 220 may have a pair of pressing members (such as a roller / roller, a belt / roller) that apply pressure to the recording medium P2. The pressure applied by the pressing members of the folding device 220 to the recording medium P2 is lower than the pressure applied by the pressing device 230 to the recording medium P2. Specifically, it is preferably 1 MPa or more and 10 MPa or less.

[0379] The crimping unit 200 may include an overlapping device that overlaps the recording medium P1 with another recording medium instead of the folding device 220. The overlapping method of the recording medium P1 and another recording medium is, for example, a method of overlapping one other recording medium on the recording medium P1, a method of overlapping one other recording medium on each of a plurality of parts on the recording medium P1, etc. The other recording medium may be a recording medium on which an image is previously formed on one or both sides, a recording medium on which no image is formed, or a previously produced crimped printed matter.

[0380] The recording medium P2 that has left the folding device 220 (or the overlapping device) is conveyed to the pressing device 230.

[0381] The pressing device 230 includes a pair of pressing members (that is, pressing rollers 231 and 232). The pressing roller 231 and the pressing roller 232 are in contact with and press against each other's outer peripheral surfaces, and apply pressure to the passing recording medium P2. The pair of pressing members included in the pressing device 230 is not limited to the combination of pressing rollers, and may also be a combination of a pressing roller and a pressing belt, or a combination of a pressing belt and a pressing belt.

[0382] When pressure is applied to the recording medium P2 passing through the pressing device 230, the transparent toner on the recording medium P2 flows due to the pressure and exhibits adhesiveness. The pressure applied by the pressing device 230 to the recording medium P2 is preferably 3 MPa or more and 300 MPa or less, more preferably 10 MPa or more and 200 MPa or less, and further preferably 30 MPa or more and 150 MPa or less.

[0383] The pressing device 230 may or may not have a heat source (such as a halogen heater) for heating the recording medium P2 inside. When the pressing device 230 has a heat source inside, the surface temperature of the recording medium P2 heated by the heat source is preferably 30°C or more and 120°C or less, more preferably 40°C or more and 100°C or less, and further preferably 50°C or more and 90°C or less. It should be noted that the pressing device 230 not having a heat source inside does not exclude the temperature inside the pressing device 230 reaching above the ambient temperature due to the heat generated by a motor or the like provided in the pressing device 230.

[0384] The recording medium P2 passes through the pressing device 230, so that the folding surfaces are bonded to each other through the flowing transparent toner, and a pressure-bonded printed matter P3 is produced. Part or all of the opposite surfaces of the pressure-bonded printed matter P3 are bonded to each other.

[0385] The completed pressure-bonded printed matter P3 is discharged from the pressing device 230.

[0386] The first type of the pressure-bonded printed matter P3 is a pressure-bonded printed matter in which the folded recording mediums are bonded to each other on the opposite surfaces through the transparent toner. The pressure-bonded printed matter P3 of this type is produced by a printed matter manufacturing device including a folding device 220.

[0387] The second type of the pressure-bonded printed matter P3 is a pressure-bonded printed matter in which two or more overlapping recording mediums are bonded to each other on the opposite surfaces through the transparent toner. The pressure-bonded printed matter P3 of this type is produced by a pressure-bonded printed matter manufacturing device including an overlapping device.

[0388] The printed matter manufacturing device of the present embodiment is not limited to a device that continuously conveys the recording medium P2 from the folding device 220 (or the overlapping device) to the pressing device 230. The printed matter manufacturing device of the present embodiment may also be a device of the following type: storing the recording medium P2 that has left the folding device 220 (or the overlapping device), and when the stored amount of the recording medium P2 reaches a predetermined amount, conveying the recording medium P2 to the pressing device 230.

[0389] In the printing material manufacturing apparatus of the present embodiment, the folding device 220 (or the overlapping device) and the crimping and pressing device 230 may be in a close arrangement or a separated arrangement. When the folding device 220 (or the overlapping device) and the crimping and pressing device 230 are separated, the folding device 220 (or the overlapping device) and the crimping and pressing device 230 are connected, for example, by a conveying unit (such as a belt conveyor) that conveys the recording medium P2.

[0390] The printing material manufacturing apparatus of the present embodiment may include a cutting unit that cuts the recording medium into a predetermined size. The cutting unit is, for example: a cutting unit disposed between the arranging unit 100 and the crimping unit 200 that cuts a part of the recording medium P1, that is, an area where the transparent toner is not arranged; a cutting unit disposed between the folding device 220 and the pressing device 230 that cuts a part of the recording medium P2, that is, an area where the transparent toner is not arranged; a cutting unit disposed downstream of the crimping unit 200 that cuts a part of the crimped print P3, that is, an area not bonded by the transparent toner, and so on.

[0391] The printing material manufacturing apparatus of the present embodiment is not limited to a single-piece device. The printing material manufacturing apparatus of the present embodiment may be a device that forms a long crimped print by performing an arranging process and a crimping process on a long recording medium and then cuts the long crimped print into a predetermined size.

[0392] Hereinafter, another example of the printing material manufacturing apparatus of the present embodiment including a color toner image forming unit is shown, but the present embodiment is not limited thereto. In the following description, the main parts shown in the drawings are described, and the description of the others is omitted.

[0393] Figure 2 It is a schematic configuration diagram showing another example of the printing material manufacturing apparatus of the present embodiment. Figure 2 The shown printing material manufacturing apparatus includes: a printing unit 300 that performs both the arrangement of the transparent toner on the recording medium and the formation of the color toner image, and a crimping unit 200 disposed downstream of the printing unit 300.

[0394] The printing unit 300 is a printing unit in a configuration of five in series and an intermediate transfer type. The printing unit 300 includes: a unit 10T for disposing a transparent toner (T); and units 10Y, 10M, 10C, and 10K for forming color toner images of respective colors of yellow (Y), magenta (M), cyan (C), and black (K). The unit 10T is a disposing unit for disposing a transparent toner on a recording medium P using a developer containing the transparent toner. The units 10Y, 10M, 10C, and 10K are units for forming color toner images on the recording medium P using developers containing color toners, respectively. The units 10T, 10Y, 10M, 10C, and 10K employ an electrophotographic method.

[0395] The units 10T, 10Y, 10M, 10C, and 10K are arranged side by side with spaces therebetween in the horizontal direction. The units 10T, 10Y, 10M, 10C, and 10K may be processing cartridges that can be loaded and unloaded into the printing unit 300.

[0396] Below the units 10T, 10Y, 10M, 10C, and 10K, an intermediate transfer belt (an example of an intermediate transfer body) 20 is provided so as to extend through each unit. The intermediate transfer belt 20 is arranged to surround a driving roller 22, a support roller 23, and an opposing roller 24 that are in contact with the inner surface of the intermediate transfer belt 20, and operates in a direction from the unit 10T toward the unit 10K. On the image holding surface side of the intermediate transfer belt 20, an intermediate transfer body cleaning device 21 is provided so as to oppose the driving roller 22.

[0397] The units 10T, 10Y, 10M, 10C, and 10K each include a developing device (an example of a developing unit) 4T, 4Y, 4M, 4C, and 4K, respectively. The developing devices 4T, 4Y, 4M, 4C, and 4K are respectively supplied with the transparent toner stored in the toner cartridges 8T, 8Y, 8M, 8C, and 8K, the yellow toner as a color toner, the magenta toner as a color toner, the cyan toner as a color toner, and the black toner as a color toner.

[0398] The units 10T, 10Y, 10M, 10C, and 10K have the same configuration and operation. Therefore, the unit 10T for disposing the transparent toner on the recording medium will be described as a representative.

[0399] Unit 10T has a photoreceptor 1T. Around the photoreceptor 1T, there are arranged in sequence: a charging roller (an example of a charging unit) 2T that charges the surface of the photoreceptor 1T; an exposure device (an example of an electrostatic image forming unit) 3T that exposes the charged surface of the photoreceptor 1T with a laser beam to form an electrostatic image; a developing device (an example of a developing unit) 4T that supplies toner to the electrostatic image and develops the electrostatic image; a primary transfer roller (an example of a primary transfer unit) 5T that transfers the developed toner image onto the intermediate transfer belt 20; and a photoreceptor cleaning device (an example of a cleaning unit) 6T that removes the toner remaining on the surface of the photoreceptor 1T after primary transfer. The primary transfer roller 5T is arranged inside the intermediate transfer belt 20 and is set at a position opposite to the photoreceptor 1T.

[0400] Hereinafter, while exemplifying the operation of unit 10T, the operations of disposing transparent toner and forming a color toner image on the recording medium P will be described.

[0401] First, the surface of the photoreceptor 1T is charged by the charging roller 2T. According to image data sent from a control unit (not shown), the exposure device 3T irradiates the charged surface of the photoreceptor 1T with a laser beam. Thereby, an electrostatic image of the arrangement pattern of transparent toner is formed on the surface of the photoreceptor 1T.

[0402] The electrostatic image formed on the photoreceptor 1T rotates to the developing position as the photoreceptor 1T rotates. And at the developing position, the electrostatic image on the photoreceptor 1T is developed by the developing device 4T, thereby being visualized to form a toner image.

[0403] Inside the developing device 4T, there is accommodated a developer containing at least transparent toner and a carrier. The transparent toner and the carrier are agitated together inside the developing device 4T, thereby triboelectrically charging and being held on the developer roller. The surface of the photoreceptor 1T passes through the developing device 4T, so that the toner electrostatically adheres to the electrostatic image on the surface of the photoreceptor 1T, and the electrostatic image is developed by the toner. The photoreceptor 1T on which the toner image with toner is formed continues to rotate, and the toner image developed on the photoreceptor 1T is conveyed to the primary transfer position.

[0404] When the toner image on the photoreceptor 1T is conveyed to the primary transfer position, a primary transfer bias is applied to the primary transfer roller 5T, and an electrostatic force from the photoreceptor 1T towards the primary transfer roller 5T acts on the toner image, transferring the toner image on the photoreceptor 1T onto the intermediate transfer belt 20. The toner remaining on the photoreceptor 1T is removed and recovered in the photoreceptor cleaning device 6T. The photoreceptor cleaning device 6T is, for example, a cleaning blade, a cleaning brush, etc., and preferably a cleaning brush.

[0405] In units 10Y, 10M, 10C, and 10K, the same operations as in unit 10T are performed using a developer containing a color toner. The intermediate transfer belt 20 with a transparent toner layer on which a transparent toner is transferred in unit 10T passes successively through units 10Y, 10M, 10C, and 10K, and color toner images of each color are transferred onto the intermediate transfer belt 20 multiple times.

[0406] The intermediate transfer belt 20 on which multiple transfers of 5-color toner images (i.e., a transparent toner layer and 4-color color toner images) are performed by passing through units 10T, 10Y, 10M, 10C, and 10K reaches the secondary transfer section, which is composed of the intermediate transfer belt 20, an opposed roller 24 in contact with the inner surface of the intermediate transfer belt, and a secondary transfer roller (an example of a secondary transfer unit) 26 disposed on the image holding surface side of the intermediate transfer belt 20. On the other hand, the recording medium P is fed by a supply mechanism to the gap where the secondary transfer roller 26 contacts the intermediate transfer belt 20, and a secondary transfer bias is applied to the opposed roller 24. At this time, an electrostatic force acting from the intermediate transfer belt 20 toward the recording medium P acts on the toner image, and the toner image on the intermediate transfer belt 20 is transferred onto the recording medium P.

[0407] The recording medium P on which the toner image is transferred is conveyed to a heat fixing device (an example of a heat fixing unit) 28. The heat fixing device 28 includes a heating source such as a halogen heater and heats the recording medium P. The surface temperature of the recording medium P heated by the heat fixing device 28 is preferably 150°C or higher and 220°C or lower, more preferably 155°C or higher and 210°C or lower, and further preferably 160°C or higher and 200°C or lower. By passing through the heat fixing device 28, the color toner image is heat-fixed onto the recording medium P.

[0408] From the viewpoints of suppressing the peeling of the transparent toner from the recording medium P and improving the fixing property of the color toner image on the recording medium P, the heat fixing device 28 is preferably a device that applies pressure while heating, and for example, it can be a pair of fixing members (roller / roller, belt / roller) having a heating source inside. When pressure is applied by the heat fixing device 28, the pressure applied by the heat fixing device 28 to the recording medium P can be lower than the pressure applied by the pressing device 230 to the recording medium P2, specifically, preferably 0.2 MPa or higher and 1 MPa or lower.

[0409] The recording medium P passes through the printing unit 300 to form a recording medium P1 to which a color toner image and a transparent toner are applied. The recording medium P1 is conveyed to the crimping unit 200.

[0410] Figure 2 The configuration of the crimping unit 200 in Figure 1It is the same as the crimping unit 200, and for the crimping unit 200, detailed descriptions of its constitution and operation are omitted.

[0411] In the printing material manufacturing apparatus of the present embodiment, the printing unit 300 and the crimping unit 200 can be in a close manner or in a separated manner. When the printing unit 300 and the crimping unit 200 are separated, the printing unit 300 and the crimping unit 200 are connected, for example, by a conveying unit (such as a belt conveyor) that conveys the recording medium P1.

[0412] The printing material manufacturing apparatus of the present embodiment may include a cutting unit that cuts the recording medium into a predetermined size. The cutting unit is, for example: a cutting unit disposed between the printing unit 300 and the crimping unit 200 and cutting a part of the recording medium P1, that is, an area where no transparent toner is disposed; a cutting unit disposed between the folding device 220 and the pressing device 230 and cutting a part of the recording medium P2, that is, an area where no transparent toner is disposed; a cutting unit disposed downstream of the crimping unit 200 and cutting a part of the crimped printing material P3, that is, an area not bonded by the transparent toner, and so on.

[0413] The printing material manufacturing apparatus of the present embodiment is not limited to a single-piece type apparatus. The printing material manufacturing apparatus of the present embodiment may be a form of apparatus that performs a color toner image forming process, a disposing process, and a crimping process on a long recording medium to form a long crimped printing material and then cuts the long crimped printing material into a predetermined size.

[0414] <Processing cartridge group>

[0415] The processing cartridge group of the present embodiment will be described.

[0416] The processing cartridge group of the present embodiment includes a first processing cartridge and a second processing cartridge. The first processing cartridge includes a first electrostatic image developing agent that accommodates a color toner in the toner group of the present embodiment and electrostatically develops a color toner image formed on the surface of the photoreceptor into a color toner image by the first electrostatic image developing agent. The second processing cartridge includes a second electrostatic image developing agent that accommodates a transparent toner in the toner group of the present embodiment and electrostatically develops a transparent toner layer formed on the surface of the photoreceptor into a transparent toner layer by the second electrostatic image developing agent. The processing cartridge group of the present embodiment is a processing cartridge group that can be loaded and unloaded in the printing material manufacturing apparatus.

[0417] Each processing cartridge constituting the processing cartridge group of the present embodiment may be a configuration including a developing unit and at least one selected from a photoreceptor, a charging unit, an electrostatic image forming unit, a transfer unit, etc. as needed.

[0418] An example of the processing cartridge group of the present embodiment is shown below, but the present embodiment is not limited thereto. In the following description, the main parts shown in the drawings will be described, and the descriptions of the others will be omitted.

[0419] Figure 3 It is a schematic configuration diagram showing an example of the first processing cartridge constituting the processing cartridge group of the present embodiment.

[0420] Figure 3 The illustrated processing cartridge 500 is detachably mounted, for example, on Figure 1 or Figure 2 the printing material manufacturing apparatus shown.

[0421] The processing cartridge 500 is a cartridge integrally formed by a photosensitive drum 501, a charging roller 502 (an example of a charging unit) provided around the photosensitive drum 501, a developing device 504 (an example of a developing unit), and a photosensitive drum cleaning device 506 (an example of a cleaning unit) through a housing 517. The housing 517 has an opening 518 for exposure. The housing 517 has a mounting rail 516, and through the mounting rail 516, the processing cartridge 500 is mounted in the printing material manufacturing apparatus.

[0422] Figure 3 Also shown is an exposure device 503, a transfer device 505, and a recording medium P disposed around the processing cartridge 500 when the processing cartridge 500 is mounted in the printing material manufacturing apparatus.

[0423] <Toner Cartridge Group>

[0424] The toner cartridge group of the present embodiment includes a first toner cartridge containing the color toner in the toner group of the present embodiment and a second toner cartridge containing the transparent toner in the toner group of the present embodiment. The toner cartridge group of the present embodiment is a toner cartridge group that is detachably mounted in the printing material manufacturing apparatus. Each toner cartridge constituting the toner cartridge group contains supplementary toner for supplying to the developing unit provided in the printing material manufacturing apparatus.

[0425] Figure 2 The illustrated printing unit 300 has a configuration in which a toner cartridge group composed of toner cartridges 8T, 8Y, 8M, 8C, and 8K can be mounted and detached, and developing devices 4T, 4Y, 4M, 4C, and 4K are respectively connected to the toner cartridges 8T, 8Y, 8M, 8C, and 8K by toner supply pipes (not shown). The toner cartridge 8T, which is the first toner cartridge constituting the toner cartridge group of the present embodiment, contains transparent toner. On the other hand, the toner cartridges 8Y, 8M, 8C, and 8K, which are the second toner cartridges constituting the toner cartridge group of the present embodiment, contain yellow, magenta, cyan, and black color toners, respectively. When the toner contained in the toner cartridge decreases, replace the toner cartridge.

[0426] Example

[0427] The present embodiment will be described in detail below by way of examples, but the present embodiment is not limited to these examples. In the following description, "parts" and "%" are based on mass unless otherwise specified.

[0428] [Example A]

[0429] [Preparation of Resin Particles for Transparent Toner Core]

[0430] (Preparation of Resin Particle Dispersion (A1) for Core)

[0431]

[0432] The above components were mixed and dissolved to prepare Solution A.

[0433] On the other hand, 10 parts of an anionic surfactant (manufactured by Dow Chemical Company, DOWFAX 2A1) was dissolved in 250 parts of ion-exchanged water, and the above Solution A was added and dispersed in a flask for emulsification (monomer emulsion A).

[0434] In addition, 1 part of the same anionic surfactant (manufactured by Dow Chemical Company, DOWFAX 2A1) was dissolved in 555 parts of ion-exchanged water and put into a polymerization flask. A reflux tube was provided on the polymerization flask, and while injecting nitrogen, stirring was slowly carried out, and the polymerization flask was heated to 75 °C by a water bath and maintained.

[0435] 9 parts of ammonium persulfate was dissolved in 43 parts of ion-exchanged water, and was added dropwise to the polymerization flask containing the anionic surfactant aqueous solution via a metering pump over 20 minutes, and then monomer emulsion A was added dropwise via a metering pump over 200 minutes.

[0436] Then, while continuously stirring, the polymerization flask was maintained at 75 °C for 3 hours, and the first-stage polymerization was completed. Thus, a precursor of the resin particle dispersion (A1) for the core in which styrene-based resin particles having a volume average particle diameter of 200 nm, a glass transition temperature of 53 °C, and a weight average molecular weight of 34,000 were dispersed was obtained.

[0437] Next, after the temperature was lowered to room temperature (25 °C), 240 parts of 2-ethylhexyl acrylate, 160 parts of n-butyl acrylate, and 1200 parts of ion-exchanged water were added to a polymerization flask containing the precursor of the core resin particle dispersion (A1), and the mixture was slowly stirred for 2 hours. Then, while continuously stirring, the temperature was raised to 70 °C, and 4.5 parts of ammonium persulfate and 100 parts of ion-exchanged water were added dropwise via a metering pump over 30 minutes. Then, after maintaining for 3 hours while continuously stirring, the polymerization was terminated. Through the above steps, a core resin particle dispersion (A1) in which composite resin particles with a volume average particle diameter of 220 nm, a weight average molecular weight of 132,000, and a number average molecular weight of 18,000 (molecular weight distribution 7.33) were dispersed and the solid content was adjusted to 30 mass% by adding ion-exchanged water was obtained.

[0438] The resin particles of the obtained core resin particle dispersion (A1) were dried to prepare a specimen in which the dried resin particles were embedded in an epoxy resin. Then, the specimen was cut with a diamond knife to prepare a cross-sectional slice of the resin particles. Then, after staining the cut surface of the specimen with ruthenium tetroxide vapor, confirmation was carried out by observation with a transmission electron microscope. The cross-sectional observation result of the resin particles confirmed that the resin particles were composed of regions in which a plurality of low-Tg (meth)acrylate resins were dispersed in a high-Tg styrene resin as the base material.

[0439] In addition, the glass transition temperature Tg behavior of the dried resin particles was analyzed from -150 °C to 100 °C using a differential scanning calorimeter (DSC) manufactured by Shimadzu Corporation, and a glass transition due to the low-Tg (meth)acrylate resin was observed at -60 °C. In addition, a glass transition due to the high-Tg styrene resin was observed at 53 °C (glass transition temperature difference: 113 °C).

[0440] (Preparation of Core Resin Particle Dispersions (A2 to A3))

[0441] The addition amounts of 2-ethylhexyl acrylate and butyl acrylate after preparing the precursor of the core resin particle dispersion (A1) were changed as shown in Table 1, and core resin particle dispersions (A2) to (A3) with a solid content adjusted to 30 mass% were obtained in the same manner as the core resin particle dispersion (A1) except for this.

[0442] The volume average particle diameter, weight average molecular weight, number average molecular weight, and glass transition temperature difference of the composite resin particles contained in the core resin particle dispersions (A2) to (A3) are shown in Table 1, respectively.

[0443] [Table 1]

[0444]

[0445] <Preparation of Resin Particle Dispersion Liquid for Transparent Toner Case Part>

[0446] (Preparation of Resin Particle Dispersion Liquid (B1) for Case Part)

[0447]

[0448] Mix and dissolve the above components to prepare Solution B.

[0449] On the other hand, dissolve 10 parts of an anionic surfactant (manufactured by Dow Chemical Company, DOWFAX 2A1) in 250 parts of ion-exchanged water, add and disperse the above Solution B in a flask, and perform emulsification (monomer emulsion B).

[0450] In addition, dissolve 1 part of the same anionic surfactant (manufactured by Dow Chemical Company, DOWFAX 2A1) in 555 parts of ion-exchanged water, and put it into a polymerization flask. A reflux tube is provided on the polymerization flask, and while injecting nitrogen, stir slowly, heat the polymerization flask to 75 °C by a water bath, and maintain it.

[0451] Dissolve 9 parts of ammonium persulfate in 43 parts of ion-exchanged water, add it dropwise to the polymerization flask containing the anionic surfactant aqueous solution via a metering pump over 20 minutes, and then add monomer emulsion B dropwise via a metering pump over 200 minutes.

[0452] Then, while continuously stirring, maintain the polymerization flask at 76 °C for 3 hours to complete the first-stage polymerization. Thus, a resin particle dispersion liquid (B1) for the case part is obtained, in which styrene-based resin particles with a volume average particle diameter of 190 nm, a glass transition temperature of 53 °C, a weight average molecular weight of 32,000, and a number average molecular weight of 15,000 are dispersed, and the solid content is adjusted to 30 mass% by supplementing ion-exchanged water.

[0453] <Preparation of Anti-Sticking Agent Dispersion Liquid for Transparent Toner>

[0454] (Preparation of Anti-Sticking Agent Dispersion Liquid (1))

[0455] · Fischer-Tropsch wax: 270 parts

[0456] (Manufactured by Nippon Seiro Co., Ltd., trade name: FNP-0090, melting temperature = 90 °C)

[0457] · Anionic surfactant: 1.0 part

[0458] (Manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK)

[0459] · Ion-exchanged water: 400 parts

[0460] Mix the above components and heat to 95°C. After dispersion using a homogenizer (manufactured by IKA, ULTRA-TURRAX T50), perform a dispersion treatment for 360 minutes using a Manton Gaulin high-pressure homogenizer (manufactured by Gaulin) to prepare an anti-sticking agent dispersion liquid (1) (solid content concentration: 20% by mass) in which anti-sticking agent particles with a volume average particle diameter of 0.23 μm are dispersed.

[0461] <Production of transparent toner particles>

[0462] (Production of transparent toner particles (T1))

[0463] · Resin particle dispersion liquid (A1) for the core part: 840 parts

[0464] · Anti-sticking agent dispersion liquid (1): 8 parts

[0465] · Colloidal silica aqueous solution: 13 parts

[0466] (Manufactured by Nissan Chemical Industries, Ltd., Snowtex OS)

[0467] · Ion-exchanged water: 800 parts

[0468] · Anionic surfactant: 1 part

[0469] (Manufactured by Dow Chemical Co., Ltd., Dowfax 2A1)

[0470] Put the above components as materials for forming the core part into a 3-liter reaction vessel equipped with a thermometer, a pH meter, and a stirrer. After adding 1.0% by mass of nitric acid to make the pH 3.0 at a temperature of 25°C, disperse at 5000 rpm using a homogenizer (manufactured by IKA Japan Co., Ltd., ULTRA-TURRAX T50), and at the same time add 4 parts of the prepared 10% by mass aqueous polyaluminum chloride solution, and further disperse for 6 minutes.

[0471] Then, a stirrer and a jacketed resistance heater are set in the reaction vessel. The rotation speed of the stirrer is adjusted to fully stir the slurry. Meanwhile, the temperature is raised to 40°C at a rate of 0.2°C per minute and then raised at a rate of 0.05°C per minute starting from above 40°C. The particle size is measured every 10 minutes using a Multisizer II (aperture: 50 μm, manufactured by Coulter). When the volume average particle size reaches 7.8 μm, the temperature is maintained, and 150 parts of the shell resin particle dispersion (B1) as the material for forming the shell is added over 5 minutes. After maintaining for 30 minutes, the pH is adjusted to 6.0 using a 1 mass% aqueous sodium hydroxide solution. Then, the pH is adjusted to 6.0 in the same manner every 5°C while raising the temperature at a rate of 1°C per minute to 90°C and maintaining at 96°C. The particle shape and surface properties are observed using an optical microscope and a scanning electron microscope (FE-SEM). As a result, particle coalescence is confirmed 2.0 hours after starting to maintain at 96°C. Therefore, the container is cooled to 30°C using cooling water over 5 minutes.

[0472] The cooled slurry is passed through a nylon mesh with a mesh size of 30 μm to remove coarse powder, and the toner slurry passing through the mesh is subjected to vacuum filtration using a suction device. The toner remaining on the filter paper is made as fine as possible by hand and put into ion-exchanged water 10 times the amount of the toner at a temperature of 30°C, and stirred and mixed for 30 minutes. Then, vacuum filtration is carried out using a suction device. The toner remaining on the filter paper is made as fine as possible by hand and put into ion-exchanged water 10 times the amount of the toner at a temperature of 30°C. After stirring and mixing for 30 minutes, vacuum filtration is carried out again using a suction device, and the conductivity of the filtrate is measured. The above operations are repeated until the conductivity of the filtrate is 10 μS / cm or less to wash the toner. The washed toner is finely crushed using a wet and dry granulator (crushing granulator) and then vacuum dried in a dryer at 25°C for 36 hours to obtain transparent toner particles (T1). The volume average particle size of the obtained transparent toner particles (T1) is 8.5 μm, the weight average molecular weight is 126,000, and the number average molecular weight is 17,000 (molecular weight distribution 7.41). In addition, the temperature T3 at which the transparent toner particles (T1) show a viscosity of 10,000 Pa·s under a pressure of 4 MPa is measured, and the result is 123°C. The temperature difference (T1 - T3) is 17°C, and tanδ2 is 1.2.

[0473] In addition, the cross-section of the transparent toner particles (T1) is observed using a scanning electron microscope (SEM). As a result, a sea-island structure is observed. The transparent toner particles (T1) have a core part with an island phase and a shell layer without an island phase. The sea phase contains a styrene resin, and the island phase contains a (meth)acrylate resin. The average diameter of the island phase is obtained by the above measurement method. The average diameter of the island phase is shown in Table 2.

[0474] (Production of Transparent Toner Particles (T2) to (T5))

[0475] Using the resin particle dispersion for the core part shown in Table 2 to replace the resin particle dispersion for the core part (A1), and changing the volume average particle diameter before charging 150 parts of the resin particle dispersion for the shell part (B1) in 5 minutes, transparent toner particles (T2) to (T5) were respectively produced by the same method as the transparent toner particles (T1).

[0476] The results of measuring the volume average particle diameter, weight average molecular weight, number average molecular weight, tanδ2, temperature T3, temperature difference (T1 - T3), and average diameter of the island phase of the transparent toner particles (T2) to (T5) are respectively shown in Table 2.

[0477] [Table 2]

[0478]

[0479] (Production of Externally Added Transparent Toner)

[0480] (Production of Externally Added Transparent Toner (T1))

[0481] To 100 parts of the obtained transparent toner particles (T1), 1.5 parts of hydrophobic silica (manufactured by NIPPONAEROSIL Co., Ltd., RY50) was added and mixed at 13,000 rpm for 30 seconds using a sample mill. Then, screening was performed using a vibrating sieve with a mesh of 45 μm to prepare the externally added transparent toner (T1). The volume average particle diameter of the obtained externally added transparent toner (T1) was 8.6 μm.

[0482] T1 and T2 of the externally added transparent toner (T1) were obtained by the above method, and the result satisfied Equation 3 "10°C ≤ T1 - T2".

[0483] (Production of Externally Added Transparent Toner (T2) to (T5))

[0484] Using the transparent toner particles (T2) to (T5) to replace the transparent toner particles (T1), the externally added transparent toners (T2) to (T5) were respectively produced by the same method as the externally added transparent toner (T1).

[0485] T1 and T2 of the externally added transparent toners (T2) to (T5) were obtained by the above method, and the result was that any of the externally added toners satisfied Equation 3 "10°C ≤ T1 - T2".

[0486] (Production of Transparent Electrostatic Image Developer)

[0487] (Preparation of Developer (T1))

[0488] Using a V-type blender, 8 parts of externally added transparent toner (T1) and 100 parts of the following carrier (1) are mixed to prepare a developer (T1) as a transparent electrostatic image developer.

[0489] (Preparation of Carrier (1))

[0490] 14 parts of toluene, 2 parts of styrene-methyl methacrylate copolymer (mass ratio: 80 / 20, weight average molecular weight: 70000), and 0.6 part of zinc oxide (Titanium Industry, MZ500) are mixed and stirred with a stirrer for 10 minutes to prepare a solution for forming a coating layer in which zinc oxide is dispersed. Then, this solution for forming a coating layer and 100 parts of ferrite particles (volume average particle diameter: 38 μm) are put into a vacuum degassing kneader, stirred at 60 °C for 30 minutes, further heated, and simultaneously subjected to reduced pressure degassing to dry it, thereby producing a carrier.

[0491] (Preparation of Developers (T2) to (T5))

[0492] Using externally added transparent toners (T2) to (T5) instead of externally added transparent toner (T1), developers (T2) to (T5) are respectively prepared by the same method as that of developer (T1) except for this.

[0493] (Preparation of Each Dispersion for Color Toner)

[0494] (Crystalline Polyester Resin Dispersion (A))

[0495] In a three-necked flask after heating and drying, a monomer component composed of 100 mol% of dimethyl sebacate and 100 mol% of nonanediol and 0.3 part of dibutyltin oxide as a catalyst relative to 100 parts of this monomer component are put in. Then, through a pressure reduction operation, the air in the container is made into an inert atmosphere with nitrogen, and stirring and reflux are carried out at 180 °C for 4 hours by mechanical stirring.

[0496] Then, the temperature is slowly raised to 230 °C under reduced pressure and stirred for 2 hours. After becoming a viscous state, it is air-cooled to stop the reaction, and crystalline polyester resin (1) is synthesized. By measuring the molecular weight (in terms of polystyrene conversion) using gel permeation chromatography, the weight average molecular weight (Mw) of the obtained crystalline polyester resin (1) is 15300, the number average molecular weight (Mn) is 3800, and the acid value is 13.5 mgKOH / g.

[0497] In addition, the melting point (Tm) of crystalline polyester resin (1) is measured using a differential scanning calorimeter (DSC), and as a result, a clear endothermic peak is shown, and the endothermic peak temperature is 77.2 °C.

[0498] Next, a resin particle dispersion was prepared using a crystalline polyester resin (1).

[0499] · Crystalline polyester resin (1): 90 parts

[0500] · Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku Co., Ltd.): 1.8 parts

[0501] · Ion-exchanged water: 210 parts

[0502] The above components were mixed and heated to 100 °C, dispersed using a homogenizer (manufactured by IKA, ULTRA-TURRAXT50), and then heated to 110 °C using a pressure ejection type Gorin homogenizer and dispersed for 1 hour to obtain a crystalline polyester resin dispersion (A) having a volume average particle diameter of 210 nm and a solid content of 30 mass%.

[0503] (Amorphous polyester resin dispersion (A))

[0504] · Bisphenol A propylene oxide adduct: 80 mol%

[0505] · Bisphenol A ethylene oxide 2 mol adduct: 20 mol%

[0506] · Terephthalic acid: 60 mol%

[0507] · Fumaric acid: 20 mol%

[0508] · Dodecenyl succinic anhydride: 20 mol%

[0509] The monomer components in the above ratios were charged into a 5 L flask equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a rectifying column. It took 1 hour to raise the temperature to 190 °C. After confirming that the reaction system was stirred evenly, 1.2 parts of dibutyltin oxide was added per 100 parts of the above monomer components. The water generated was further distilled off, and at the same time, it took 6 hours to raise the temperature from this temperature to 240 °C, and the dehydration condensation reaction was further continued at 240 °C for 2 hours to obtain an amorphous polyester resin (1) as an amorphous polyester resin having a glass transition temperature of 63 °C, an acid value of 10.5 mgKOH / g, a weight average molecular weight of 17,000, and a number average molecular weight of 4,200.

[0510] Next, a resin particle dispersion was prepared using the obtained amorphous polyester resin (1).

[0511] · Amorphous polyester resin (1): 100 parts

[0512] · Ethyl acetate: 50 parts

[0513] Ethyl acetate was put into a 5-L detachable flask, and then the above resin components were slowly added. Stirring was carried out using a three-in-one motor until complete dissolution to obtain an oil phase. In this stirred oil phase, a total of 2 parts of 10% by mass aqueous ammonia solution was slowly added dropwise using a dropper, and further 230 parts of ion-exchanged water was slowly added dropwise at a rate of 10 ml / min for phase transfer emulsification. Further, the pressure was reduced using an evaporator while performing desolvation to obtain an amorphous polyester resin dispersion (A). The volume average particle diameter of the amorphous polyester resin particles in this dispersion was 120 nm, and the solid content concentration was 30% by mass.

[0514] (Amorphous polyester resin dispersion (B))

[0515] · Bisphenol A propylene oxide adduct: 50 mol%

[0516] · Bisphenol A ethylene oxide 2-mol adduct: 50 mol%

[0517] · Trimellitic anhydride: 5 mol%

[0518] · Terephthalic acid: 85 mol%

[0519] · Dodecenyl succinic anhydride: 10 mol%

[0520] Among the monomer components in the above ratios, monomers other than trimellitic anhydride were used, and the reaction was carried out according to the synthesis of the above amorphous polyester resin (1) until the softening point reached 110 °C. That is, the monomer components in the above ratios (except trimellitic anhydride) were put into a 5-L flask equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a rectifying column. It took 1 hour to raise the temperature to 190 °C. After confirming that the reaction system was stirred evenly, 1.2 parts of dibutyltin oxide was added to 100 parts of the above monomer components. Further, the generated water was distilled off, and at the same time, it took 6 hours to raise the temperature from this temperature to 240 °C, and the dehydration condensation reaction was continued at 240 °C for 2 hours.

[0521] Next, the temperature was lowered to 190 °C, and 5 mol% of trimellitic anhydride was slowly added. The reaction was continued at this temperature for 2 hours to obtain an amorphous polyester resin (2) as an amorphous polyester resin having a glass transition temperature of 63 °C, an acid value of 15.3 mgKOH / g, a weight average molecular weight of 49,000, and a number average molecular weight of 7,000.

[0522] Next, a resin particle dispersion was prepared using the amorphous polyester resin (2).

[0523] In the preparation of the amorphous polyester resin dispersion (A), the amorphous polyester resin (2) was used instead of the amorphous polyester resin (1), and the amorphous polyester resin dispersion (B) was obtained according to the preparation of the amorphous polyester resin dispersion (A) except for this. The volume average particle diameter of the amorphous polyester resin particles in this dispersion was 220 nm, and the solid content concentration was 30% by mass.

[0524] (Colorant particle dispersion 1)

[0525] · Carbon black (manufactured by Cabot Corporation, Legal 330): 50 parts

[0526] · Anionic surfactant (manufactured by NOF Corporation, New Rex R): 2 parts

[0527] · Ion-exchanged water: 198 parts

[0528] The above components were mixed, pre-dispersed for 10 minutes using a homogenizer (manufactured by IKA Corporation, ULTRA-TURRAX), and then dispersed for 15 minutes under a pressure of 245 MPa using an Ultimater (opposite collision type wet grinder, manufactured by Sugino machine) to obtain a colorant particle dispersion 1 with a volume average particle diameter of 354 nm and a solid content of 20.0% by mass.

[0529] (Colorant particle dispersion 2)

[0530] · Cyan pigment (copper phthalocyanine, C.I.Pigment blue15:3, manufactured by Dainichi Seika): 50 parts

[0531] · Ionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku): 5 parts

[0532] · Ion-exchanged water: 195 parts

[0533] The above components were mixed, dispersed for 10 minutes using a homogenizer (manufactured by IKA Corporation, ULTRA-TURRAX), and then dispersed for 15 minutes under a pressure of 245 MPa using an Ultimater (opposite collision type wet grinder, manufactured by Sugino machine) to obtain a colorant particle dispersion 2 with a volume average particle diameter of 462 nm and a solid content of 20.0% by mass.

[0534] (Colorant particle dispersion 3)

[0535] · Magenta pigment (C.I.Pigment Red 122): 80 parts

[0536] · Anionic surfactant (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 8 parts

[0537] · Ion-exchanged water: 200 parts

[0538] Mix and dissolve the above components, disperse them for 10 minutes using a homogenizer (ULTRA-TURRAX T50, manufactured by IKA), and then irradiate them with ultrasonic waves of 28 kHz for 10 minutes using an ultrasonic disperser to obtain a colored pigment particle dispersion liquid 3 with a volume average particle diameter of 132 nm and a solid content of 29.0 mass%.

[0539] (Colored pigment particle dispersion liquid 4)

[0540] · Yellow pigment (5GX03, manufactured by Clariant): 80 parts

[0541] · Anionic surfactant (Neogen SC, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 8 parts

[0542] · Ion-exchanged water: 200 parts

[0543] Mix and dissolve the above components, disperse them for 10 minutes using a homogenizer (ULTRA-TURRAX T50, manufactured by IKA), and then irradiate them with ultrasonic waves of 28 kHz for 20 minutes using an ultrasonic disperser to obtain a colored pigment particle dispersion liquid 4 with a volume average particle diameter of 108 nm and a solid content of 29.0 mass%.

[0544] (Anti-sticking agent particle dispersion liquid 2)

[0545] · Olefin wax (melting point: 88°C): 90 parts

[0546] · Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 1.8 parts

[0547] · Ion-exchanged water: 210 parts

[0548] Mix the above components and heat them to 100°C, disperse them using a homogenizer (manufactured by IKA, ULTRA-TURRAX T50), and then heat them to 110°C using a pressure ejection type Gorin homogenizer and disperse them for 1 hour to obtain an anti-sticking agent particle dispersion liquid 2 with a volume average particle diameter of 180 nm and a solid content of 30 mass%.

[0549] (Production of color electrostatic image developer)

[0550] (Production of black toner particles 1)

[0551] · Amorphous polyester resin dispersion liquid (A): 166 parts

[0552] · Crystalline polyester resin dispersion (A): 50 parts

[0553] · Colorant particle dispersion 1: 25 parts

[0554] · Anti-sticking agent particle dispersion 2: 40 parts

[0555] Mix and disperse the above components in a round stainless steel flask using a homogenizer (ULTRA-TURRAX T50). Then, add 0.20 parts of aluminum chloride to it and continuously perform the dispersion operation using ULTRA-TURRAX T50. Stir the flask with a heating oil bath and heat it to 48 °C at the same time. After maintaining at 48 °C for 60 minutes, gradually supplement 60 parts of amorphous polyester resin dispersion (A). Then, adjust the pH of the system to 8.0 with a 0.5 mol / l sodium hydroxide aqueous solution, seal the stainless steel flask, and heat it to 90 °C while continuously stirring with a magnetic sheet and maintain for 3 hours.

[0556] After the reaction is completed, cool, filter, wash with ion-exchanged water, and perform solid-liquid separation by suction filtration using a Buchner funnel. Further redisperse it in 1 liter of ion-exchanged water at 40 °C, stir and wash for 15 minutes at 300 rpm. Repeat this operation 5 more times. When the pH of the filtrate reaches 7.5 and the conductivity reaches 7.0 μS / cm, perform solid-liquid separation by suction filtration using a Buchner funnel and No. 5A filter paper. Then, continuously perform vacuum drying for 12 hours to obtain black toner particles 1.

[0557] Measure the particle size of the black toner particles 1 using a Multisizer II. The results show that the volume average particle size D50 is 6.4 μm, the volume particle size distribution index GSDv is 1.21, and the tanδ1 at 100 °C is 3.7.

[0558] (Preparation of black toner 1)

[0559] Mix 100 parts of black toner particles 1 and 1.3 parts of hydrophobic silica with an average particle size of 30 nm (NY50, manufactured by NIPPON AEROSIL Co., Ltd.). Use a Henschel mixer to mix at a circumferential speed of 32 m / s for 10 minutes, and then remove coarse particles using a sieve with a mesh size of 45 μm to obtain black toner 1.

[0560] (Preparation of carrier (2))

[0561] · Ferrite particles (volume average particle size: 50 μm, volume resistivity: 10 8 Ωcm): 100 parts

[0562] · Toluene: 14 parts

[0563] · Perfluoro octyl ethyl acrylate / methyl methacrylate copolymer (copolymerization ratio 40 / 60, Mw: 50,000): 1.6 parts

[0564] · Carbon black (VXC-72, manufactured by Cabot Corporation): 0.12 parts

[0565] · Crosslinked melamine resin particles (number average particle diameter: 0.3 μm): 0.3 parts

[0566] Among the above components, the components other than the ferrite particles are mixed and dispersed for 10 minutes using a stirrer to prepare a liquid for forming a film. The liquid for forming a film and the ferrite particles are put into a vacuum degassing kneader, stirred at 60 °C for 30 minutes, and then toluene is removed by vacuum distillation to form a resin film on the surface of the ferrite particles, thereby manufacturing the carrier (2).

[0567] (Production of developer C1)

[0568] 94 parts of the carrier and 6 parts of black toner 1 are mixed and stirred at 40 rpm for 20 minutes using a V-type blender, and developer C1 is produced by sieving through a sieve having a mesh size of 177 μm.

[0569] (Production of developer C2)

[0570] In the production of black toner particles 1, 20 parts of colorant particle dispersion liquid 2 is used instead of colorant particle dispersion liquid 1, and cyan toner particles 1 are obtained according to the production of black toner particles 1 except for this. The volume average particle diameter D50, volume particle size distribution index, and tan δ1 of the obtained toner particles are shown in Table 3.

[0571] Using cyan toner particles 1 instead of black toner particles 1, developer C2 is obtained in the same manner as developer C1 except for this.

[0572] (Production of developer C3)

[0573] In the production of black toner particles 1, 25 parts of colorant particle dispersion liquid 3 is used instead of colorant particle dispersion liquid 1, and magenta toner particles 1 are obtained according to the production of black toner particles 1 except for this. The volume average particle diameter D50, volume particle size distribution index, and tan δ1 of the obtained toner particles are shown in Table 3.

[0574] Using magenta toner particles 1 instead of black toner particles 1, developer C3 is obtained in the same manner as developer C1 except for this.

[0575] (Production of developer C4)

[0576] In the production of the black toner particles 1, 25 parts of the colorant particle dispersion liquid 4 is used instead of the colorant particle dispersion liquid 1, and the yellow toner particles 1 are obtained in the same manner as the production of the black toner particles 1 except for this. The volume average particle diameter D50, the volume particle size distribution index, and tanδ1 of the obtained toner particles are shown in Table 3.

[0577] The developer C4 is obtained in the same manner as the developer C1 except that the yellow toner particles 1 are used instead of the black toner particles 1.

[0578] (Production of Developers C5 to C8)

[0579] The amount of the amorphous polyester resin dispersion liquid used at the initial stage of toner particle production is changed from 166 parts of the amorphous polyester resin dispersion liquid (A) to 80 parts of the amorphous polyester resin dispersion liquid (A) and 80 parts of the amorphous polyester resin dispersion liquid (B), and the amount of the amorphous polyester resin dispersion liquid added as a supplement is changed from 60 parts of the amorphous polyester resin dispersion liquid (A) to 30 parts of the amorphous polyester resin dispersion liquid (A) and 30 parts of the amorphous polyester resin dispersion liquid (B). Except for this, the black toner particles 2, the cyan toner particles 2, the magenta toner particles 2, and the yellow toner particles 2 are produced in the same manner as the black toner particles 1, the cyan toner particles 1, the magenta toner particles 1, and the yellow toner particles 1, respectively. The volume average particle diameter D50, the volume particle size distribution index, and tanδ1 of the obtained toner particles are shown in Table 3.

[0580] The developers C5 to C8 are obtained in the same manner as the developers C1 to C4 except that the black toner particles 2, the cyan toner particles 2, the magenta toner particles 2, and the yellow toner particles 2 are used instead of the black toner particles 1, the cyan toner particles 1, the magenta toner particles 1, and the yellow toner particles 1, respectively.

[0581] (Production of Developers C9 to C12)

[0582] The amount of the amorphous polyester resin dispersion liquid used at the initial stage of toner particle production is changed from 166 parts of the amorphous polyester resin dispersion liquid (A) to 166 parts of the amorphous polyester resin dispersion liquid (B), and the amount of the amorphous polyester resin dispersion liquid added as a supplement is changed from 60 parts of the amorphous polyester resin dispersion liquid (A) to 60 parts of the amorphous polyester resin dispersion liquid (B). Except for this, the black toner particles 3, the cyan toner particles 3, the magenta toner particles 3, and the yellow toner particles 3 are produced in the same manner as the black toner particles 1, the cyan toner particles 1, the magenta toner particles 1, and the yellow toner particles 1, respectively. The volume average particle diameter D50, the volume particle size distribution index, and tanδ1 of the obtained toner particles are shown in Table 3.

[0583] Using black toner particles 3, cyan toner particles 3, magenta toner particles 3, and yellow toner particles 3 to replace black toner particles 1, cyan toner particles 1, magenta toner particles 1, and yellow toner particles 1 respectively, and in other respects the same as developers C1 to C4, developers C9 to C12 were obtained respectively.

[0584] (Preparation of Developers C13 to C16)

[0585] The amount of the crystalline polyester resin dispersion (A) used in the initial stage of toner particle production was changed from 50 parts to 130 parts. In other respects the same as black toner particles 1, cyan toner particles 1, magenta toner particles 1, and yellow toner particles 1, black toner particles 4, cyan toner particles 4, magenta toner particles 4, and yellow toner particles 4 were produced respectively. The volume average particle diameter D50, volume particle size distribution index, and tanδ1 of the obtained toner particles are shown in Table 4.

[0586] Using black toner particles 4, cyan toner particles 4, magenta toner particles 4, and yellow toner particles 4 to replace black toner particles 1, cyan toner particles 1, magenta toner particles 1, and yellow toner particles 1 respectively, and in other respects the same as developers C1 to C4, developers C13 to C16 were obtained respectively.

[0587] (Preparation of Developers C17 to C20)

[0588] The amount of the crystalline polyester resin dispersion (A) used in the initial stage of toner particle production was changed from 50 parts to 20 parts. In other respects the same as black toner particles 3, cyan toner particles 3, magenta toner particles 3, and yellow toner particles 3, black toner particles 5, cyan toner particles 5, magenta toner particles 5, and yellow toner particles 5 were produced respectively. The volume average particle diameter D50, volume particle size distribution index, and tanδ1 of the obtained toner particles are shown in Table 4.

[0589] Using black toner particles 5, cyan toner particles 5, magenta toner particles 5, and yellow toner particles 5 to replace black toner particles 3, cyan toner particles 3, magenta toner particles 3, and yellow toner particles 3 respectively, and in other respects the same as developers C9 to C12, developers C17 to C20 were obtained respectively.

[0590] [Table 3]

[0591]

[0592] [Table 4]

[0593]

[0594] <Evaluation>

[0595] Fill the developers of cyan, magenta, yellow, and black and the fifth developer of the Color1000 Press retrofit machine manufactured by Fuji Xerox Co., Ltd. with the respective developers shown in Table 5. Assemble the recording paper (OK Prince Premium Paper, manufactured by Oji Paper Co., Ltd.). At a fixing temperature of 170 °C and a fixing pressure of 4.0 kg / cm 2 Set the loading amount of the transparent toner to 3 g / m 2 to form an image in which text and photographic images are mixed (set the area density to 30%), and perform fixing. As the arrangement order of the toner images, arrange the color toner images and the transparent toner layer in sequence starting from the side closer to the recording paper.

[0596] (Crimpability)

[0597] Next, bend the fixed image with the fixing surfaces overlapping, and use a crimp sealer PRESSELE LEADA (retrofit machine manufactured by Toppan Forms Co., Ltd.) to perform crimping at a pressure of 90 MPa to produce a crimped printed matter (1). Cut the crimped printed matter (1) along the long side direction. Thus, a rectangular specimen with a width of 15 mm is produced, and the peel strength is measured by a known method (90-degree peel method). The results are shown in Table 5. Note that the greater the peel strength, the better the crimpability.

[0598] (Offset)

[0599] Next, after continuously performing 1000 prints (i.e., the formation of the color toner image and the transparent toner layer and their fixing) in an environment with a temperature of 20 °C and a relative humidity of 55%, visually observe the fixing member to confirm toner fouling, and thus evaluate the offset according to the following criteria. The results are shown in Table 5.

[0600] A: No toner fouling on the fixing member was confirmed at all

[0601] B: Slight adhesion of the transparent toner was found on the surface of the fixing member, but within the allowable range

[0602] C: Adhesion of the color toner was found on the surface of the fixing member

[0603] [Table 5]

[0604]

[0605] From the above results, it can be seen that in the above embodiments, compared with the above comparative examples, the suppression of offset and crimpability are balanced.

[0606] [Reference Example B]

[0607] <Preparation of dispersion liquid containing styrene resin particles>

[0608] [Preparation of styrene resin particle dispersion (St1)]

[0609]

[0610] The above materials were mixed and dissolved to prepare a monomer solution.

[0611] 8 parts of an anionic surfactant (manufactured by Dow Chemical Company, Dowfax 2A1) was dissolved in 205 parts of ion-exchanged water, and the above monomer solution was added for dispersion and emulsification to obtain an emulsion.

[0612] 2.2 parts of an anionic surfactant (manufactured by Dow Chemical Company, Dowfax 2A1) was dissolved in 462 parts of ion-exchanged water, and it was put into a polymerization flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen inlet tube. While stirring, it was heated to 73 °C and maintained.

[0613] 3 parts of ammonium persulfate was dissolved in 21 parts of ion-exchanged water, and it was added dropwise to the above polymerization flask via a metering pump over 15 minutes, and then the above emulsion was added dropwise via a metering pump over 160 minutes.

[0614] Next, while continuously stirring slowly, the polymerization flask was maintained at 75 °C for 3 hours and then returned to room temperature.

[0615] Thus, a styrene resin particle dispersion (St1) containing styrene resin particles, with a volume average particle diameter (D50v) of the resin particles of 174 nm, a weight average molecular weight of 49 k obtained by GPC (UV detection), a glass transition temperature of 54 °C, and a solid content of 42% was obtained.

[0616] After drying the styrene resin particle dispersion (St1), the styrene resin particles were taken out, and the thermal behavior in the temperature range from -100 °C to 100 °C was analyzed using a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-60A). As a result, one glass transition temperature was observed. The glass transition temperature is shown in Table 6.

[0617] [Preparation of styrene resin particle dispersions (St2) to (St13)]

[0618] In the same manner as the preparation of the styrene resin particle dispersion (St1), but changing the monomers as described in Table 6, styrene resin particle dispersions (St2) to (St13) were prepared.

[0619] In Table 6, the monomers are described by the following abbreviations.

[0620] Styrene: St, n-Butyl acrylate: BA, 2-Ethylhexyl acrylate: 2EHA, Ethyl acrylate: EA, 4-Hydroxybutyl acrylate: 4HBA, Acrylic acid: AA, Methacrylic acid: MAA, 2-Carboxyethyl acrylate: CEA

[0621] [Table 6]

[0622]

[0623] <Preparation of Dispersion Liquid Containing Composite Resin Particles>

[0624] [Preparation of Composite Resin Particle Dispersion (M1)]

[0625]

[0626] The above materials were put into a polymerization flask, stirred at 25 °C for 1 hour, and then heated to 70 °C.

[0627] 2.5 parts of ammonium persulfate was dissolved in 75 parts of ion-exchanged water and added dropwise to the above polymerization flask via a metering pump over 60 minutes.

[0628] Next, while continuously stirring slowly, the polymerization flask was maintained at 70 °C for 3 hours and then returned to room temperature.

[0629] Thus, a composite resin particle dispersion (M1) containing composite resin particles, with a volume average particle diameter (D50v) of the resin particles of 219 nm, a weight average molecular weight of 219k obtained by GPC (UV detection), and a solid content of 32% was obtained.

[0630] After drying the composite resin particle dispersion (M1), the composite resin particles were taken out, and the thermal behavior in the temperature range from -150 °C to 100 °C was analyzed using a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-60A). As a result, two glass transition temperatures were observed. The glass transition temperatures are shown in Table 7.

[0631] [Preparation of Composite Resin Particle Dispersions (M2) to (M21) and (cM1) to (cM3)]

[0632] In the same manner as the preparation of the composite resin particle dispersion (M1), but changing the styrene resin particle dispersion (St1) as described in Table 7, or changing the polymerization components of the (meth)acrylate resin as described in Table 7, composite resin particle dispersions (M2) to (M21) and (cM1) to (cM3) were prepared.

[0633] [Preparation of Composite Resin Particle Dispersion (M22) - (M27)]

[0634] The composite resin particle dispersions (M22) - (M27) were prepared in the same manner as the preparation of the composite resin particle dispersion (M1), but adjusting the amounts of 2-ethylhexyl acrylate and n-butyl acrylate used.

[0635] In Table 7, the monomers are described by the following abbreviations.

[0636] Styrene: St, n-butyl acrylate: BA, 2-ethylhexyl acrylate: 2EHA, ethyl acrylate: EA, 4-hydroxybutyl acrylate: 4HBA, acrylic acid: AA, methacrylic acid: MAA, 2-carboxyethyl acrylate: CEA, hexyl acrylate: HA, propyl acrylate: PA

[0637] [Table 7]

[0638]

[0639] [Preparation of Toner]

[0640] [Preparation of Toner (1) and Developer (1)]

[0641] · Composite resin particle dispersion (M1): 504 parts

[0642] · Ion-exchanged water: 710 parts

[0643] · Anionic surfactant (manufactured by Dow Chemical Company, Dowfax 2A1): 1 part

[0644] Put the above materials in a reaction vessel equipped with a thermometer and a pH meter. After adjusting the pH to 3.0 by adding 1.0% nitric acid aqueous solution at a temperature of 25°C, disperse it at a rotation speed of 5000 rpm using a homogenizer (manufactured by IKA, ULTRA-TURRAX T50), and simultaneously add 23 parts of 2.0% aluminum sulfate aqueous solution. Then, install a stirrer and a jacketed resistance heater in the reaction vessel, heat it to a temperature of 40°C at a heating rate of 0.2°C / minute, start heating at a heating rate of 0.05°C / minute from above 40°C, and measure the particle size using a Multisizer II (pore size 50 μm, manufactured by Beckman Coulter) every 10 minutes. When the volume average particle size reaches 5.0 μm, maintain the temperature and add 170 parts of a styrene-based resin particle dispersion (St1) over 5 minutes. After the addition is completed, maintain the temperature at 50°C for 30 minutes, then add 1.0% sodium hydroxide aqueous solution to adjust the pH of the slurry to 6.0. Then, adjust the pH to 6.0 every 5°C and simultaneously heat it to 90°C at a heating rate of 1°C / minute, and maintain it at 90°C. Observe the particle shape and surface properties using an optical microscope and a field emission scanning electron microscope (FE-SEM). As a result, particle coalescence was confirmed at the 10th hour. Therefore, cool the container to 30°C using cooling water over 5 minutes.

[0645] Pass the cooled slurry through a nylon mesh with a mesh size of 15 μm to remove coarse particles, and subject the slurry passing through the mesh to reduced-pressure filtration using a suction device. Crush the solid component remaining on the filter paper as finely as possible by hand, put it into ion-exchanged water (temperature 30°C) at 10 times the solid content, and stir for 30 minutes. Then, perform reduced-pressure filtration using a suction device, crush the solid component remaining on the filter paper as finely as possible by hand, put it into ion-exchanged water (temperature 30°C) at 10 times the solid content, stir for 30 minutes, and then perform reduced-pressure filtration using a suction device again to measure the conductivity of the filtrate. Repeat the above operations until the conductivity of the filtrate is 10 μS / cm or less to wash the solid component.

[0646] Crush the washed solid component using a wet and dry granulator (crushing and granulating machine), and vacuum dry it in an oven at 25°C for 36 hours to obtain toner particles (1). The volume average particle size of the toner particles (1) is 8.0 μm.

[0647] Mix 100 parts of the toner particles (1) and 1.5 parts of hydrophobic silica (manufactured by NIPPON AEROSIL Co., Ltd., RY50) and mix them at a rotational speed of 13000 rpm for 30 seconds using a sample mill. Perform sieving using a vibrating sieve with a mesh size of 45 μm to obtain toner (1).

[0648] Using the toner (1) as a sample, the thermal behavior in the temperature range from -150°C to 100°C was analyzed using a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-60A), and as a result, two glass transition temperatures were observed. The glass transition temperatures are shown in Table 8.

[0649] The temperature T1 and temperature T2 of the toner (1) were obtained by the above measurement method, and as a result, the toner (1) satisfied the formula 3 "10°C ≤ T1 - T2".

[0650] The cross-section of the toner (1) was observed by a scanning electron microscope (SEM), and as a result, a sea-island structure was observed. The toner (1) has a core portion where the island phase exists and a shell layer where the island phase does not exist. The sea phase contains a styrene-based resin, and the island phase contains a (meth)acrylate-based resin. The average diameter of the island phase was obtained by the above measurement method. The average diameter of the island phase is shown in Table 8.

[0651] 10 parts of the toner (1) and 100 parts of the following resin-coated carrier were placed in a V-type blender and stirred for 20 minutes. Then, sieving was performed using a vibrating sieve with a mesh of 212 μm to obtain the developer (1).

[0652]

[0653] The above materials except for the ferrite particles and glass beads (diameter 1 mm, the same amount as toluene) were mixed, and using a sand mill manufactured by Kansai Paint Co., Ltd., stirring was performed at a rotational speed of 1200 rpm for 30 minutes to obtain a dispersion. The dispersion and the ferrite particles were placed in a vacuum degassing kneader, and while stirring, reduced pressure drying was performed to obtain the resin-coated carrier.

[0654] [Preparation of Toners (2) to (27) and Developers (2) to (27)]

[0655] In the same manner as the preparation of the toner (1), but changing the composite resin particle dispersion and the styrene-based resin particle dispersion as described in Table 8, toners (2) to (27) and developers (2) to (27) were prepared.

[0656] The temperature T1 and temperature T2 of the toners (2) to (27) were obtained by the above measurement method, and as a result, the toners (2) to (27) all satisfied the formula 3 "10°C ≤ T1 - T2".

[0657] [Preparation of Comparative Toners (c1) to (c3) and Developers (c1) to (c3)]

[0658] In the same manner as the preparation of the toner (1), but changing the composite resin particle dispersion liquid and the styrene resin particle dispersion liquid as described in Table 8, toners (c1) to (c3) and developers (c1) to (c3) were prepared.

[0659] [Evaluation of Pressure-Responsive Phase Transfer]

[0660] The temperature difference (T1 - T3), which is an index indicating the ease of phase transfer of the toner due to pressure, was determined. Each toner was used as a sample, and the temperature T1 and the temperature T3 were measured using a flow tester (manufactured by Shimadzu Corporation, CFT-500), and the temperature difference (T1 - T3) was calculated. The temperature difference (T1 - T3) is shown in Table 8.

[0661] [Evaluation of Adhesiveness]

[0662] As a printing material manufacturing apparatus, an apparatus as shown in Figure 2 the following manner was prepared. That is, a printing material manufacturing apparatus was prepared that includes: a printing unit having a tandem and intermediate transfer method for simultaneously disposing a transparent toner and forming a colored image, and a crimping unit having a folding device and a pressing device.

[0663] A transparent toner, a yellow toner, a magenta toner, a cyan toner, and a black toner were respectively placed in the five developing devices included in the printing unit. The yellow toner, magenta toner, cyan toner, and black toner were commercially available products manufactured by Fuji Xerox Co., Ltd.

[0664] As the recording medium, postcard paper V424 manufactured by Fuji Xerox Co., Ltd. was used.

[0665] The image formed on the postcard paper was set to an image with an area density of 30% in which black text and a full-color photographed image were mixed, and was formed on one side of the postcard paper.

[0666] The application amount of the transparent toner was set to 3 g / m on the image formation area of the image formation surface of the postcard paper 2 .

[0667] The folding device was set to a device that folds the postcard paper in half with the image formation surface on the inside.

[0668] The pressing device was set to a pressure of 90 MPa.

[0669] Under the above-mentioned apparatus and conditions, 10 postcards were continuously manufactured that were folded in half with the image formation surface on the inside and the image formation surfaces were adhered to each other.

[0670] The 10th postcard was cut along the long side with a width of 15 mm to produce a rectangular test piece, and a 90-degree peel test was conducted. The peel speed of the 90-degree peel test was set at 20 mm / minute, and the load (N) from 10 mm to 50 mm after the start of measurement was collected at intervals of 0.4 mm, and its average value was calculated. Further, the loads (N) of three test pieces were averaged. The load (N) required for peeling was classified as follows. The results are shown in Table 8.

[0671] A: 0.8 N or more

[0672] B: 0.6 N or more and less than 0.8 N

[0673] C: 0.4 N or more and less than 0.6 N

[0674] D: 0.2 N or more and less than 0.4 N

[0675] E: less than 0.2 N

[0676] [Table 8]

[0677]

Claims

1. A toner group, comprising: a color toner and a transparent toner having pressure transferability, wherein the color toner contains a polyester resin, and the transparent toner contains a vinyl resin, the transparent toner contains a styrene resin and a (meth)acrylate resin, the styrene resin contains styrene and other vinyl monomers in the polymerization components, and the (meth)acrylate resin contains at least two alkyl acrylates selected from the group consisting of propyl acrylate, n-butyl acrylate, n-hexyl acrylate, and 2-ethylhexyl acrylate in the polymerization components, and the mass ratio of the at least two alkyl acrylates in the whole polymerization components is 90% by mass or more, the other vinyl monomers contained as polymerization components in the styrene resin contain (meth)acrylate, the transparent toner has a core part containing the styrene resin and the (meth)acrylate resin and a shell layer covering the core part, and the shell layer contains the styrene resin, when the tanδ at 100 °C of the color toner is set as tanδ1 and the tanδ at 100 °C of the transparent toner is set as tanδ2, tanδ1 is 1.0 or more and 4.0 or less, and tanδ1 and tanδ2 satisfy the following formula 1, Formula 1: 1.2 ≤ tanδ1 / tanδ2 ≤ 3.

0.

2. The toner group according to claim 1, wherein, tanδ1 is 1.5 or more and 3.5 or less.

3. The toner group according to claim 1 or claim 2, wherein, tanδ1 and tanδ2 satisfy the following formula 2, Formula 2: 1.5 ≤ tanδ1 / tanδ2 ≤ 2.

9.

4. The toner group according to claim 1 or claim 2, wherein, the transparent toner has at least two glass transition temperatures, and the difference between the lowest glass transition temperature and the highest glass transition temperature is 30 °C or more.

5. The toner group according to claim 1 or claim 2, wherein, the mass ratio of styrene in the whole polymerization components of the styrene resin is 60% by mass or more and 95% by mass or less.

6. The toner group according to claim 1 or claim 2, wherein, the mass ratio of the two with the largest mass ratio among the at least two acrylates contained as polymerization components in the (meth)acrylate resin is 80:20 to 20:

80.

7. The toner group according to claim 1 or claim 2, wherein, the two with the largest mass ratio among the at least two (meth)acrylates contained as polymerization components in the (meth)acrylate resin are (meth)alkyl acrylates, and the difference in the number of carbon atoms of the alkyl groups of the two (meth)alkyl acrylates is 1 or more and 4 or less.

8. The toner group according to claim 1 or claim 2, wherein, the other vinyl monomers contained as polymerization components in the styrene resin contain at least one of n-butyl acrylate and 2-ethylhexyl acrylate.

9. The toner group according to claim 1 or claim 2, wherein, the styrene resin and the (meth)acrylate resin contain the same (meth)acrylate as a polymerization component.

10. The toner group according to claim 1 or claim 2, wherein, the (meth)acrylate resin contains 2-ethylhexyl acrylate and n-butyl acrylate as polymerization components.

11. The toner group according to claim 1 or claim 2, wherein, the content of the styrene resin is more than the content of the (meth)acrylate resin.

12. The toner group according to claim 1 or claim 2, wherein, the toner group has: a sea phase containing the styrene resin and an island phase containing the (meth)acrylate resin dispersed in the sea phase.

13. The toner group according to claim 12, wherein, the average diameter of the island phase is 200 nm or more and 500 nm or less.

14. A developer group, which has: a first electrophotographic image developer containing the color toner in the toner group according to any one of claims 1 to 13, and a second electrophotographic image developer containing the transparent toner in the toner group according to any one of claims 1 to 13.

15. A toner cartridge group, which is loaded and unloaded in a printing material manufacturing apparatus, the toner cartridge group has: a first toner cartridge containing the color toner in the toner group according to any one of claims 1 to 13, and a second toner cartridge containing the transparent toner in the toner group according to any one of claims 1 to 13.

16. A process cartridge group, which is loaded and unloaded in a printing material manufacturing apparatus, the process cartridge group has: a first process cartridge having a first developing unit, the first developing unit containing a first electrophotographic image developer containing the color toner in the toner group according to any one of claims 1 to 13, and electrostatically developing a color toner image formed on the surface of a photoreceptor into a color toner image by the first electrophotographic image developer; and a second process cartridge having a second developing unit, the second developing unit containing a second electrophotographic image developer containing the transparent toner in the toner group according to any one of claims 1 to 13, and electrostatically developing a transparent toner layer formed on the surface of a photoreceptor into a transparent toner layer by the second electrophotographic image developer.

17. A printing material manufacturing apparatus, which includes: a color toner image forming unit, which contains a first electrophotographic image developer containing the color toner in the toner group according to any one of claims 1 to 13, and forms a color toner image on a recording medium by electrophotography using the first electrophotographic image developer; A cell that houses a second electrostatic image developer containing the transparent toner in the toner group according to any one of claims 1 to 13, and forms a transparent toner layer by electrophotographically disposing the transparent toner on a recording medium; A heat fixing unit that includes a fixing member and heat-fixes the color toner image on the recording medium in a state where the fixing member is in contact with the transparent toner layer; and A crimping unit that crimps the recording medium on which the color toner image is heat-fixed by folding or crimps the recording medium on which the color toner image is heat-fixed with another recording medium in an overlapping manner.

18. A method for manufacturing a printed matter, which comprises: A color toner image forming step of forming a color toner image on a recording medium by electrophotography using a first electrostatic image developer containing the color toner in the toner group according to any one of claims 1 to 13; A disposing step of forming a transparent toner layer by electrophotographically disposing the transparent toner in the toner group according to any one of claims 1 to 13 on the recording medium; A heat fixing step of heat-fixing the color toner image on the recording medium in a state where a fixing member is in contact with the transparent toner layer; and A crimping step of crimping the recording medium on which the color toner image is heat-fixed by folding or crimping the recording medium on which the color toner image is heat-fixed with another recording medium in an overlapping manner.

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